BRUEL & KJAER/BRUEL KJAER 2238 Basic SLM Software

User Manual: BRUEL & KJAER/BRUEL & KJAER 2238 Basic SLM Software

Open the PDF directly: View PDF .
Page Count: 165 [warning: Documents this large are best viewed by clicking the View PDF Link!]

Technical

Documentation

English BB1119 – 11

2238 Mediator

Integrating Sound Level Meter

Basic SLM Software BZ7126

February 1999

Brüel & Kjær BB1119 – 11

2238 Mediator

Integrating Sound Level Meter

Basic SLM Software BZ 7126

0–4 Brüel & Kjær2238 Mediator

User Manual

Trademarks

2238 Mediator is a trademark of Brüel&Kjær A/S. Microsoft, Win-

dows, and MS-DOS are trademarks of Microsoft Corporation.

distributed in any form, or by any means, without prior consent in writ-

ing from Brüel & Kjær Sound & Vibration Measurement A/S, Nærum,

Denmark.

BB1119 – 11 0–5

2238 Mediator

User Manual

Contents

About this manual and the 2238 Mediator. Overview of

measurement parameters, menus and navigation

Basic introduction to the Mediator: Fitting batteries, pushkey

definitions, Measurement Window and changing the language

Explains how to set up parameters in the System menu

Explains how to set up parameters in the Measurement Set-up menu

Explains how to perform simple measurements: Calibrating,

starting a new measurement, measurement control and changing

the displayed measurement parameters

Explains how the data file system works: Storing, recalling, printing

and deleting data

Explains how to export data to a PC and post-processing programs,

how to set up a printer

Service, repair, care, cleaning and storage of the Mediator

Introduction

Getting Started

The System Menu

The Measurement Set-up Menu

Measuring

Data Handling

Printing and Transferring Data

Maintenance and Repair

0–6 Brüel & Kjær2238 Mediator

User Manual

9Specifications for the Mediator

Specifications

10 Appendix 1: General

Appendix 2: Interface

Index

Information about: Exchange Rate, listing of default parameters and

interface error messages

Explains the programming and operation of the serial interface for

the Mediator: Formats for interface messages, setting up the PC and

interface jobs

BB1119 – 11 1–1

2238 Mediator

User Manual

Chapter 1

Introduction

1.1 About this Manual.............................................................. 1–2

Summary of Contents........................................................ 1 – 2

About this Volume............................................................. 1 – 3

1.2 About the 2238 Mediator ................................................. 1 – 4

How the Mediator Works .................................................. 1 – 5

Application Programs........................................................ 1 – 5

1.3 Measurement Parameters............................................... 1 – 7

1.4 Menu Structure.................................................................. 1 – 10

Navigation........................................................................ 1 – 10

System Menu ................................................................... 1 – 11

Measurement Set-up Menu ............................................ 1 – 11

Calibration Menu ............................................................ 1 – 12

File System ...................................................................... 1 – 12

1.5 Backlight ............................................................................... 1 – 14

Chapter 1 – Introduction

About this Manual

1–2 Brüel & Kjær2238 Mediator

User Manual

1.1 About this Manual

1.1.1 Summary of Contents

●Chapter 1 – Introduction: provides a general overview

of the Mediator and its functions.

●Chapter 2 – Getting Started: provides basic informa-

tion including: replacing batteries, using the pushkeys,

reading the screen, and setting the language.

●Chapter 3 – System Menu: provides an overview of the

System menu and gives instructions for setting up the

parameters.

●Chapter 4 – Measurements Set-up Menu: provides an

overview of the Measurement Set-up menu and gives

instructions for setting up the measurement parameters.

●Chapter 5 – Measuring: gives instructions for calibrat-

ing the Mediator and for checking the calibration and the

calibration history. It provides information about starting

a new measurement.

●Chapter 6 – Data Handling: contains information and

instructions about using the file managing system.

●Chapter 7 – Printing and Transferring Data: pro-

vides information about outputting data to a printer or

a PC and setting up the output connectors.

●Chapter 8 – Maintenance and Repair: gives informa-

tion about care, cleaning and storage and contains service

and repair information.

●Chapter 9 – Specifications: – technical specifications.

●Appendix 1: General: – describes the exchange rate

parameter and lists the default parameters and interface

error messages.

●Appendix 2: Interface: – gives a general description of

the terminology for the interface messages and instruc-

tions for using the interface commands and queries

●Index

Chapter 1– Introduction

About this Manual

BB1119 – 11 1–3

2238 Mediator

User Manual

1.1.2 About this Volume

This volume of the User Manual deals with all the general

aspects of handling and setting up the Mediator and includes

instructions for the functionality of the Basic version (Basic

SLM Software BZ7126). If your Mediator has been upgraded

to other version(s), you must refer to the associated User

Manual(s) for the special functions related to these software

versions.

Conventions Used in this Manual

Pushkeys

References to buttons on the 2238 Mediator are shown with

the pushkey’s pictogram as it appears on the instrument (for

example ). Refer to section 2.3 for a complete list of button

pictograms and their functions.

Soft Keys

Mediator has two “soft keys” that have different functions

depending on the current context. The soft keys functions are

denoted by chevrons (<>) and courier type face. The current

functions of the soft keys are always shown on the display.

The soft key can have the following functions: <Select>,

<Save>, <Ok> or <Menu>. The soft key can have func-

tions: <Cancel>, <Undo> or <Close>. This is similar to

the functionality from the familiar Windows environment.

Parameter Text

Text which refers directly to text on the instrument’s screen

or printouts is indicated using a Courier type face.

For example: Press until Language is highlighted in the

System menu.

Sockets

Reference to sockets is made in bold type face (for example,

Aux 1)

Chapter 1 – Introduction

About the 2238 Mediator

1–4 Brüel & Kjær2238 Mediator

User Manual

1.2 About the 2238 Mediator

Standards

2238 Mediator Integrating Sound Level Meter complies with

the coming IEC1672 Class 1 standard. This standard will

supersede the IEC651 and IEC 804 Type 1 standards. This

implies that the Mediator also complies with current inter-

national and national standards. The Mediator is categorized

as a Group X sound level meter according to IEC 1672, i.e. a

self-contained battery-operated instrument that requires no

external connections to other apparatus to measure sound

levels.

Basic Configuration

The Mediator comprises the following:

●2238 Mediator Integrating Sound Level Meter

●Basic SLM Software BZ 7126

●Microphone Preamplifier ZC 0030

●Prepolarized free-field 1/2″ Condenser Microphone Type

4188

●9-pole cable with 25-pole Adaptor AO 1386 (null-modem

cable for serial interface)

●Shoulder Bag KE 0323

●Protective Cover UA1236

●4×Alkaline Batteries QB 0013

1.2.1 How Mediator Works

The Mediator can be configured to a wide range of require-

ments with different software packages or a combination of

these packages. You can easily upgrade the software via the

serial RS – 232 interface or it can be performed at a

Brüel & Kjær service centre. The Frequency Analysis Soft-

ware option requires Type 2238 – A – F (with filter set) or a

hardware upgrade (installation of filter set 2238MUF), that

Chapter 1– Introduction

About the 2238 Mediator

BB1119 – 11 1–5

2238 Mediator

User Manual

must be made at a Brüel& Kjær service centre. If the Medi-

ator is ordered with Frequency Analysis Software BZ 7123,

the filter set is part of the instrument.

Refer to the block diagram in Fig.1.1 for an overview of how

the Mediator works. The signal from the microphone is fed

through the appropriate amplifiers, the desired filters (“A”,

“C”, “L” or octave filters (if fitted)) and correction filters

(“Sound Incidence”, “Windscreen”). The multiplexer switches

two signals (either the same signal or with different weight-

ings) through to the RMS and the RMS/Peak detectors and

succeeding Time Weighting filters. At this point the signals

are still in the analogue domain. The signals are now con-

verted in the D/A-converter and all subsequent signal process-

ing is in the digital domain. Finally the signals are fed

through the D/A-converter and the buffered signals are out-

put to the Aux 1 and Aux 2 connectors via the multiplexer.

Detectors

One of the main features of the Mediator is that it contains

two detectors with independent frequency weighting func-

tions. In the basic package, one is an RMS detector and the

other a Peak detector. Linear and A- and C-weighting can be

selected for both detectors. F (Fast), S (Slow) and I (Impulse)

time weighting must be selected in the basic version. Both

frequency and time weightings must be selected before a

measurement is performed.

1.2.2 Application Programs

The following software modules are available for upgrading

the Mediator:

●Frequency Analysis Software BZ 7123 — general purpose

module for scanning 1/1- and 1/3-octave bands. BZ7123

requires the 1/1-octave and 1/3-octave filter set (2238

MUF). If the Filter Set has already been installed, you

can order BZ7123 alone. Refer to ordering information

in the associated Product Data sheet.

●Logging SLM Software BZ7124 — allows a large range

of parameters to be logged. This module allows logging

Chapter 1 – Introduction

About the 2238 Mediator

1–6 Brüel & Kjær2238 Mediator

User Manual

of all relevant parameters from Enhanced SLM Software

BZ 7125.

●Enhanced SLM Software BZ 7125 — adds a number of

powerful features to the basic version. Including: statis-

tics, back-erase function and the possibility of two simul-

taneous RMS measurements.

Fig.1.1 Simplified block diagram for 2238 Mediator

L-filter MUX Aux 1

Aux 2

A-filter

C-filter

Overload detector

1/1- and 1/3-Octave

Filter Set

Correction filter

(Sound Incidence,

Windscreen)

Amplifier

10 dB/step

(Cal. adjustment)

Preamplifier

MUX

Buffer

AC out

RMS

detector

Time weighting1

Buffer

DC out

Peak/RMS2

detector

Digital control

and processing

Power supply

Display

Keys

Microphone

RMS 1 RMS 23PEAK AUX1/23

External

power

supply

980091e

Batteries 6V

(4 x AA size)

Serial

interface

1 No time weighting with peak detector

2 Only peak detector in basic version

3 Not available in Basic Version

Chapter 1– Introduction

Measurement Parameters

BB1119 – 11 1–7

2238 Mediator

User Manual

Filter Set

The 1

/1-octave and 1/3-octave filter set is required with the

frequency analysis module, but the filter set can be installed

and used with all modules. In this case the filter bands are

available as a frequency weighting that can be selected man-

ually.

Changing Application

Push the key to display the System menu from which

you can select the desired application module. Refer to section

4.1 in Chapter 3 for more details about the System menu.

1.3 Measurement Parameters

Table 1.1 lists the discrete parameters available with the

Basic package. The X and Y suffixes in the parameter names

refer respectively to frequency weightings (A, C or L) and

time weightings (S, F or I).

You can change the displayed parameters during measure-

ment or in pause mode. Press the key to enter set-up

mode and use the and keys to select (highlight) the

desired parameter in the Measurement Window. Use the

or keys to change the parameter. When you have set up

the desired parameters, exit the set-up mode by going to the

top or the bottom of the window with the or keys.

Chapter 1 – Introduction

Measurement Parameters

1–8 Brüel & Kjær2238 Mediator

User Manual

Detector 1 — RMS Parameters

Parameter Default

screen

parameter Definition Freq.

Weight-

ing

Time

Weighting

LXeq LAeq Equivalent continuous level

for the duration of the

measurement as defined

by IEC 1672

“A”, “C”

or “L” –

LXYav4 LAFav4 Averaged sound level with

an Exchange Rate of 4 dB

(LDOD)

“A”, “C”

or “L” “F” or “S”

LXYav5 LAFav5 Averaged sound level with

an Exchange Rate of 5 dB

(LOSHA)

“A”, “C”

or “L” “F” or “S”

LXE LAE Frequency weighted sound

exposure level for the dura-

tion of the measurement as

defined by IEC1672

(SEL, 1 s)

“A” –

LXep,d LAFep,d Daily Personal Noise Expo-

sure. Recommended by

EEC Directive EEC/86/188

“A” –

EAEA,d Total sound exposure for

the duration of the meas-

urement in Pa2h

––

LXYp LAFp Sound pressure level

(SPL) “A”, “C”

or “L” “F”, “S” or

“I”

LXYmax LAFmax Max. LXYp value detected

within the elapsed time

“A”, “C”

or “L” “F”, “S” or

“I”

LXYmin LAFmin Min. LXYp value detected

within the elapsed time

“A”, “C”

or “L” “F”, “S” or

“I”

LXYinst LAFInst Randomly sampled instan-

taneous value of RMS level “A”, “C”

or “L” “F”, “S” or

“I”

Table 1.1 Parameters available with the Basic package

Chapter 1– Introduction

Measurement Parameters

BB1119 – 11 1–9

2238 Mediator

User Manual

Detector 2 — Peak Parameters

LXpk LCpk Instantaneous peak level “C” or

“Lin.” –

LXpkmax LCpkmax Max. Peak level detected

during the measurement “C” or

“Lin.” –

General – other parameters

Number of

Peaks #cPeaks Counts the number of sec-

onds where a specified

peak level is exceeded dur-

ing a measurement

“C” or

“Lin.” –

Dose%XADose The dose percentage

based on the LXeq (3 dB

exchange rate)

“A” “F” or “S”

Dose%XY4 AFDose4 The dose percentage

based on the Lav and a

4 dB exchange rate

“A” “F” or “S”

Dose%XY5 AFDose5 The dose percentage

based on the Lav and a

5 dB exchange rate

“A” “F” or “S”

Overload% Over-

load%

The percentage of time that

an overload occurred dur-

ing a measurement

––

Under-

range% Under-

range% The percentage of time that

an underrange occurred

during a measurement

––

Elapsed

Time Elapsed

Time The amount of time that

has passed since the cur-

rent measurement began

(measurement time exclud-

ing pauses)

––

Start Time Start

Time

The start time for the cur-

rent measurement ––

Table 1.1 (Cont.) Parameters available with the Basic package

Chapter 1 – Introduction

Menu Structure

1–10 Brüel & Kjær2238 Mediator

User Manual

1.4 Menu Structure

Mediator has four main menu modes, each initiated by a

dedicated hard key:

● System menu. section 1.4.2

● Measurement Set-up menu. See section 1.4.3 below

● Calibration menu. See section 5.1

● Data Files. See section 1.4.5 below

The Mediator must be in pause mode before you can select

one of the these menus.

1.4.1 Navigation

Press the desired main menu hard key (see above) when the

normal Measurement Window is displayed. Use the and

keys to step through the available Settings. The selected

Setting is indicated as inverse text. Press the <Cancel> soft

key if you want to go to another menu.

Note: You must always revert to the Measurement Window

before you can change menu.

When you reach a Setting you want to change, press the

<Select> soft key or the cursor key. The set-up

options for that setting are displayed. The first set-up line

you can change is indicated as inverse text. If there are other

set-up lines on the screen you can select them with the

and keys.

Start Date Start

Date The start date for the cur-

rent measurement ––

Time Time The current time – –

Table 1.1 (Cont.) Parameters available with the Basic package

Chapter 1– Introduction

Menu Structure

BB1119 – 11 1–11

2238 Mediator

User Manual

Use the and keys to change the parameter you want

to change. Press the <Save> soft key to save the new param-

eter setting. If you change a parameter by mistake, press the

<Cancel> soft key or the Meas. Results key to revert

to the previous setting. The <Cancel> soft key steps one

level up, the Meas. Results key reverts to the Measurement

Window.

If you press a key that is not allowed or irrelevant in the current

set-up, the Illegal Entry symbol will appear for a second

in the upper right hand corner of the display.

1.4.2 System Menu

Pushing the key will display the System menu. For more

information about setting up basic system parameters, see

Chapter 3.

For selecting/setting up:

●Application (for selecting software module)

●Date & Time (for setting the date and time)

●Serial Interface (for setting up the serial interface pa-

rameters)

●Printer Interface (for setting up the printer interface pa-

rameters)

●Language (for selecting the user interface language)

●Display (for setting the display contrast)

●Standards (lists the standards that the Mediator complies

with. Also shows the installed software modules)

●About (system information)

1.4.3 Measurement Set-up Menu

Pushing the key will display the Measurement Set-up

menu. For more information about setting up the Mediator

for measurement, see Chapter 4.

980310

Chapter 1 – Introduction

Menu Structure

1–12 Brüel & Kjær2238 Mediator

User Manual

The following Settings are available:

●General (for setting the measurement range, the Peaks

Over level and the second exchange rate)

●Weightings (for setting the frequency weightings for

Detector 1 and 2)

●Measurement Control (for setting up an Auto Start meas-

urement

●Correction Filters (for selecting correction filters for

sound incidence and windscreen)

●Input/Output (for setting up the Aux 1 and Aux 2 sock-

ets)

●Auto Start (for selecting an Auto Start)

●Occupational Health (for setting up the Occupational

Health parameters)

●Save Setup (for saving a measurement set-up)

●Recall Setup (for recalling a measurement set-up)

Note: You can also change the measurement range by press-

ing the key.

1.4.4 Calibration Menu

Pushing the key will display the Calibration menu. Refer

to Chapter 4 for more information.

●Calibration (for calibrating the Mediator)

●Calibration History (contains information about the ini-

tial calibration and the 20 latest calibrations)

1.4.5 File System

Memory

Data files, measurement settings, calibration data and cal-

endar data (date and time) are all saved in RAM. This mem-

ory is maintained when you turn off the instrument. If the

Chapter 1– Introduction

Menu Structure

BB1119 – 11 1–13

2238 Mediator

User Manual

batteries are removed, the back-up battery will retain the

memory for minimum 6 months (if charged), so that data is

saved.

The serial number and some internal calibration factors are

stored in Flash RAM, which is a non-volatile memory.

Buffer

Holds all of the measurement results from the last measure-

ment period. The buffer is updated once a second. It is cleared

each time you start a measurement with the key. Results

in the buffer can be output to a printer or saved in a file.

Data Files

Measurements are saved in Mediator as files with a file

number and an extension. In addition the files can be iden-

tified by the date and time when the file was saved.

You can normally store up to 500 files for each software

package. However, the number of files may be reduced if a

large amount of data is occupied by the Logging module. A

warning is displayed if there is not sufficient memory for the

current measurement.

All files are preserved when you turn off the instrument,

except for the data in the buffer. All measurement data are

copied from the buffer. Measurements can be stored automat-

ically (measurements with a preset measurement time) or

manually (at any time after a measurement is paused).

A basic measurement data file consists of a group of set-up

data and a group of associated measurement data. The set-

up data are:

●Serial number for the Mediator

●Initial calibration parameters

●Calibration set-up

●Measurement set-up

Chapter 1 – Introduction

Backlight

1–14 Brüel & Kjær2238 Mediator

User Manual

Measurement data are:

●Set-up and Calibration data

●Broadband RMS data

●Broadband Peak data

For more information about Data Files, see Chapter 5.

1.5 Backlight

The backlight makes the display easier to read in low light

situations. Press to turn it on or off. To save batteries,

the light will switch off automatically after 30 seconds.

BB1119 – 11 2–1

2238 Mediator

User Manual

Chapter 2

Getting Started

2.1 Getting Started..................................................................... 2–2

2.2 Fitting Batteries .................................................................. 2 – 2

Checking the Battery Level .............................................. 2 – 2

Using an External Power Supply ..................................... 2 – 4

The Back-up Battery ......................................................... 2 – 4

Switching the Mediator On and Off ................................. 2 – 5

Dismantling/Mounting the Microphone........................... 2 – 5

2.3 Pushkey Definitions........................................................... 2 – 8

2.4 Measurement Window .................................................... 2 – 10

2.5 Changing the Language ................................................. 2 – 12

Chapter 2 – Getting Started

Getting Started

2–2 Brüel & Kjær2238 Mediator

User Manual

2.1 Getting Started

As supplied from the factory, the Mediator is fitted complete

with microphone and input stage. You only need to fit the

batteries before the instrument is ready for measuring

2.2 Fitting Batteries

Fitting Batteries for the First Time:

1. The battery compartment is located in the centre of the

back of the instrument. Press the two tabs on the upper

edge of the battery compartment and remove the lid.

2. Insert new batteries (four 1.5 V LR6/AA size alkaline

batteries) following the +/– orientation shown in the bot-

tom of the battery compartment.

3. Press the compartment lid back into place.

Note: If you cannot switch on the Mediator after inserting

the batteries, check that you have inserted them correctly.

The Mediator will not switch on if the batteries are inserted

incorrectly, however, it will not be damaged.

2.2.1 Checking the Battery Level

The battery symbol in the upper right hand corner of the

Measurement Window indicates the current battery level.

When the battery is full, the battery level indicator is fully

black. As the batteries are used, the level will fall until the

indicator is completely empty. When it is time to replace the

batteries, the indicator will be empty and blinking.

The battery level indicator has five indication lines in it. Each

line represents approximately 20% of remaining battery time

(at room temperature), see Fig.2.1. When the indicator is

empty and blinking, there is less than 15 minutes left. Under

Chapter 2– Getting Started

Fitting Batteries

BB1119 – 11 2–3

2238 Mediator

User Manual

extreme cold or hot environments, the remaining time may

be less.

Caution

It is possible for batteries to explode or leak if they are

handled incorrectly, so:

●For long-term storage, remove the batteries and keep the

sound level meter in a dry place.

Note: For very long-term storage (more than 6 month)

you must save the files and settings on a PC, if required.

See section 2.2.3.

●Never mix different makes or types of battery.

●Never mix new and old batteries.

Note: Rechargeable batteries can be used, however, the op-

erating time may vary considerably, depending on the type

and condition of the cells. The batteries will not be charged

when using an external power supply for the Mediator, they

must be charged outside the instrument.

Fig.2.1 Interpreting the battery level indicator

980337e

Batteries full, 100% left

80% left

60% left

40% left

20% left

Replace batteries, approx 15 minutes left

Chapter 2 – Getting Started

Fitting Batteries

2–4 Brüel & Kjær2238 Mediator

User Manual

2.2.2 Using an External Power Supply

The sound level meter can be powered from a regulated 7 –

15 V DC supply via the External Power socket on the base

(e.g. from a mains supply adaptor, see ordering information

in Product Data). The power supply must be able to supply

minimum 400mA in the nominal voltage range. Maximum

allowable ripple from the adaptor is 100 mVpeak-peak.

You can connect the external power supply even when the

batteries are installed. The sound level meter automatically

selects the source with the highest supply voltage. The ex-

ternal power supply will not damage the batteries and it will

not charge rechargeable batteries.

Note: It is recommended that batteries are always fitted

when using an external power supply. This prevents loss of

power if the external supply is accidentally disconnected.

2.2.3 The Back-up Battery

The sound level meter has a back-up battery for running the

clock and maintaining the data files, even when it is switched

off or the main batteries are removed. Other data, including

the serial number, the microphone serial number and cali-

bration data, are stored in Flash RAM and will remain irre-

spective of the back-up battery. If the back-up battery is flat,

a “Preparing file system” message will appear when the in-

strument is switched on and files in the memory are lost.

The back-up battery is recharged automatically when there

are standard batteries in the sound level meter. It is fully

charged after about 10 hours. Fully charged, the back-up bat-

tery runs the clock and retains records and settings for about

6 months. These charge times are typical for a sound level

meter at room temperature.

Chapter 2– Getting Started

Fitting Batteries

BB1119 – 11 2–5

2238 Mediator

User Manual

2.2.4 Switching the Mediator On and Off

Switching On

Press . The Brüel & Kjær logo is displayed for a few seconds

before the Measurement Window appears. The instrument

returns to pause mode with the set-up it had when it was

last switched off.

Default Set-up

You can revert to the default set-up by recalling Default

from the Save/Recall Window in the Measurement Set-up

menu, see section 4.1.11. All results in the buffer are deleted

and the instrument returns to the default set-up in pause

mode. Refer to section 10.2 in Appendix 1 for a list of default

parameters.

Switching Off

The Mediator can only be switched off from pause mode. Press

to enter pause mode and then press to switch off

the instrument. Even when the instrument is switched off,

the memory circuits are still energized and all settings and

saved measurement data are maintained.

2.2.5 Dismantling/Mounting the Microphone

If it is required to dismantle/mount the microphone, note the

following precautions:

●When screwing on the microphone, input stage, protec-

tion grid and extension cables, do it gently to avoid

damaging the threads.

●Keep dust and foreign matter off the microphone dia-

phragm. Do not touch the diaphragm with anything —

it is very delicate. Small amounts of dust on the dia-

phragm will not affect the microphone response.

2–6 Brüel & Kjær2238 Mediator

User Manual

Dismantling/Mounting the Microphone and Input Stage

The microphone supplied with the Mediator is the Prepolar-

ized Free-field 1/2″ Microphone Type 4188 that requires no

external polarization voltage.

1. Unscrew the threaded retaining ring (see Fig. 2.2) that

secures the input stage. The input stage can now be

removed from the input stage socket at the top of the

Mediator.

Fig.2.2 Mounting the input stage and microphone onto the sound level

meter. 5-pin DIN connectors are used

Chapter 2– Getting Started

Fitting Batteries

BB1119 – 11 2–7

2238 Mediator

User Manual

2. Unscrew the microphone from the Input Stage ZC0030.

Do not remove the protection grid from the microphone.

Fitting is the reverse of dismantling.

Connecting a Microphone Extension Cable

Two optionally available extension cables can be used with

the Mediator:

●AO 0561 3 m long

●AO 0560 10 m long

Note: Older cables Types AO 0408 and AO 0409 can also be

used.

Fig.2.3 Connecting a microphone extension cable to the sound level meter

Chapter 2 – Getting Started

Pushkey Definitions

2–8 Brüel & Kjær2238 Mediator

User Manual

To Connect:

1. Insert the microphone extension cable into the input

stage. Secure the connection by turning the threaded

retaining ring.

2. Insert the other end of the microphone extension cable

into the input stage socket and secure by turning the

threaded retaining ring. (see Fig. 2.3).

Note: Connecting a recommended microphone extension ca-

ble has no effect on the sound level meter’s calibration. There-

fore, you do not have to re-calibrate after connecting one of

the recommended microphone extension cables.

2.3 Pushkey Definitions

Each pushkey on the sound level meter’s front panel is

marked with a pictogram. This section gives a brief explana-

tion of the buttons.

Power Press this key to switch the instru-

ment on or off. The instrument will

be in pause mode when started up.

Calibrate Press this key to calibrate your in-

strument. See section 5.1 for cali-

bration instructions.

System Press this key to display the Sys-

tem menu for configuring the in-

strument and for changing

application programs. See section

4.1 in Chapter 3 for system options.

Data Files Press this key to select the Data

Files menu. The menu options in

this window allows you to save,

print and edit printout files and to

access the File Manager facility.

Chapter 2– Getting Started

Pushkey Definitions

BB1119 – 11 2–9

2238 Mediator

User Manual

Set-up Press this key to access/step

through the set-up options in the

Measurement Set-up menu. See

section 4.1.2 in Chapter 3 for de-

tails about the available settings.

Up/Down Arrows Press these keys to step up/down

in the menu items in the selected

window. Also for entering/exiting

edit mode in the Measurement

Window.

Left/Right Arrows Press these keys to select the pa-

rameters in the selected window.

Note: For the sake of consistency

the keys are always used

to select menu items, and the

keys are always used to se-

lect values.

Range Press this key to access the Range

Setting menu. Use the

keys to step through the available

measurement ranges or scroll with

the key.

Reset Resets the current measurement

data and sets the buffer and timer

to zero. If a measurement is in

progress, it will continue immedi-

ately after reset. If the instrument

is paused, it will still be paused

after pressing Reset.

Note: If a measurement has been

in progress for more than a minute

a warning is displayed and you

must confirm the command before

any data is deleted.

Meas. Results Press this key in any of the set-up

menus to return to the Measure-

Chapter 2 – Getting Started

Measurement Window

2–10 Brüel & Kjær2238 Mediator

User Manual

ment Window. If menu changes

have not been saved, they will be

cancelled.

Pause/Continue Press this key to pause/continue

the current measurement. If the

sound level meter is in pause mode,

the measurement is continued

without resetting data or the timer.

Select Softkey with functions <Select>,

<Save>, <Recall> or <Ok> de-

pending on the cursor position in

the current menu. The <Menu>

function displays the File Manager

Options Window.

Cancel Softkey with functions <Cancel>,

<Undo> or <Close> depending on

the cursor position in the current

menu.

Backlight Switches the display’s backlight on

or off. To save batteries, the back-

light switches off automatically af-

ter 30 seconds.

2.4 Measurement Window

During normal operation the Measurement Window is used

to view the measured data. It provides several kinds of in-

formation about your settings and measurements.

1. Bar graph: This is a quasi-analogue display that shows

a graphical representation of the current sound pressure

level (Inst.), based on the RMS value from Detector1. It

is updated 5 times a second.

a. The bottom end of the measurement range (in dB): All

sound below this level will register as under-range. To

change the starting point for the measurement range,

2–11 Brüel & Kjær2238 Mediator

User Manual

press while measurement is paused, you can then

step up the measurement range.

b. The upper end of the measurement range (in dB) and

overload indicator: Peaks above this level will trigger

an “OVERLOAD” indication that will appear under the

bar graph, see Fig. 2.5. If an overload has occurred in

the last one second, this indication will stay for the

next second. This indication will appear both in pause

mode and in measurement mode. If an overload occurs

during a measurement in progress, a “latched over-

load” symbol will appear to the right of the bar graph,

see Fig. 2.5. The latched overload remains until the

measurement is reset, also if the measurement is

paused. To change the measurement range, press .

Fig.2.4 The Measurement Window

Fig.2.5 Overload indicators

980335e

Bargraph

Battery Indicator

Illegal Entry

Value Fields

Run/Pause Indicator

Parameter Fields

980336e

Overload indicator Latched overload symbol

Chapter 2 – Getting Started

Changing the Language

2–12 Brüel & Kjær2238 Mediator

User Manual

2. Run/Pause indicator: Displays the current status of

measurement. Press to continue or pause

a measurement. Press to start a “new” measurement

(resetting measurement data and the timer).

3. Battery level: When the batteries are new, the indi-

cator is completely black. As the batteries are used, the

level falls. Replace the batteries when this indicator is

empty and blinking.

4. Parameter fields: Specifies the measurement parameters

5. Value fields: Indicates the measurement values for the

selected parameters.

6. Illegal Entry: The symbol lights up for a second if

you press a key that has no function in the current win-

dow.

2.5 Changing the Language

The default user interface language for the Mediator is Eng-

lish.

How to Change the Language

The following languages can be selected

●English

●Français

●Deutsch

●Italiano

●Español

1. From the Measurement Window press the hard key

to select the System menu.

2. Select the Language menu item with the cursor

keys and enter by pressing the <Select> softkey.

980310

Chapter 2– Getting Started

Changing the Language

BB1119 – 11 2–13

2238 Mediator

User Manual

3. Select the language you want to install by using the

or keys.

4. When the desired language is displayed, press the

<Save> softkey to enter the selection.

5. Press the <Cancel> softkey twice to return to the

Measurement Window, or press the Meas. Results

key.

2–14 Brüel & Kjær2238 Mediator

User Manual

BB1119 – 11 3–1

2238 Mediator

User Manual

Chapter 3

System Menu

3.1 System Menu......................................................................... 3–2

Introduction ....................................................................... 3 – 2

Selecting the System Menu and Parameters................... 3 – 2

Selecting Application Module ........................................... 3 – 4

Setting the Date and Time................................................ 3 – 4

Setting up the Serial Interface Parameters..................... 3 – 5

Setting up the Printer Interface Parameters................... 3 – 6

Choosing the Language..................................................... 3 – 7

Adjusting the Display Contrast........................................ 3 – 7

Displaying the International Standards.......................... 3 – 8

Displaying System Information........................................ 3 – 8

Chapter 3 – System Menu

System Menu

3–2 Brüel & Kjær2238 Mediator

User Manual

3.1 System Menu

3.1.1 Introduction

This chapter explains how to set up basic parameters in the

System menu, such as application program, interface and

language. Once these parameters are set up, they are not

normally changed until a measurement session is completed.

3.1.2 Selecting the System Menu and Parameters

The System menu is used for setting up and reading basic

system parameters. It contains the menu items shown in

Fig. 3.1.

1. The System menu is accessed by pressing the System

key when the instrument is paused. If the instrument is

measuring you must press to pause. Select the de-

sired menu item with the cursor keys.

This will also cause the <Select> and <Close> soft keys

to appear.

2. Press the <Select> softkey or the cursor key

to enter the selection.

This will also cause the <Ok> and <Cancel> soft keys to

appear.

Fig.3.1 The System menu. The arrows to the left indicate that there is

more than one window

Chapter 3 – System Menu

System Menu

BB1119 – 11 3–3

2238 Mediator

User Manual

Alternatively you can step through the menu items by press-

ing the System key repeatedly. The first time you press the

key the System menu is displayed and the following key clicks

steps you directly through the menu items, starting with the

first item in the menu.

The arrows on the left-hand side of some of the screens in-

dicate that there is more than one screen page. These pages

are cyclic, i.e., when you pass the top or the bottom line of

the menu you automatically go the bottom or top line of the

next/previous page, respectively.

Selecting Parameters

1. Select the desired parameter from the sub-menu with the

cursor keys.

2. Then use the cursor keys to step through the avail-

able settings or values of that parameter until the one

you need is displayed.

The range of available settings for each parameter is

given in the following sections.

Note: If you want to change a parameter value, you may

hold the cursor keys down to automatically in-

crease or decrease the value.

3. Press the <Ok> soft key to confirm the selection. If you

wish to undo any of these, press the <Cancel> soft key

and all settings/values will revert to what they were the

last time the <Select> soft key was pressed.

4. Repeat steps 1, 2 and 3 until you are satisfied with the

setting or value of each parameter.

5. Press the <Close> softkey to revert to the Measurement

Window after you have pressed the <Ok> or <Cancel> key.

Note: Normally you can use the Meas. Result key to

go directly from a menu to the Measurement Window.

Chapter 3 – System Menu

System Menu

3–4 Brüel & Kjær2238 Mediator

User Manual

3.1.3 Selecting Application Module

Select the desired application module from the Application

Window. You can only select the application modules that

have been installed in the instrument. Refer to the associated

User Manuals for installation of application modules.

The currently possible options are:

●Enhanced SLM — Enhanced SLM Software BZ7125

●Freq. Anal. SLM — Frequency Analysis Software

BZ 7123

●Logging SLM — Logging SLM Software BZ7124

3.1.4 Setting the Date and Time

The Date & Time Window has the appearance as shown in

Fig. 3.3.

Fig.3.2 The Application Window. This example contains three applica-

tion modules (the Basic SLM Software is always installed)

Fig.3.3 The Date & Time Window

Chapter 3 – System Menu

System Menu

BB1119 – 11 3–5

2238 Mediator

User Manual

You can set:

●Year

●Month

●Date

●Time

The clock is running while you set the date and time. Simply

step the clock settings forwards or backwards until the clock

is synchronized with the real time.

3.1.5 Setting up the Serial Interface Parameters

The Baud Rate and Handshake interface parameters can be

set up from the Serial Interface Window illustrated in

Fig. 3.4. Notice that these parameters are used only for con-

trol via the RS 232 interface.

You must set up the interfaces of the Mediator and the in-

strument connected to the serial interface socket to the same

baud rate and handshake settings to enable communication.

Setting the Baud Rate

●4800 ●9600

●19200 ●38400

●115200

Select the desired baud rate in the Baud Rate field.

Fig.3.4 The Serial Interface Window

Chapter 3 – System Menu

System Menu

3–6 Brüel & Kjær2238 Mediator

User Manual

Selecting Handshake

●Hardwired

●Modem

Select the desired type of handshake in the Handshake field.

3.1.6 Setting up the Printer Interface Parameters

You can set up separate Baud Rate and Handshake interface

parameters for a printer, in the Printer Interface Win-

dow illustrated in Fig.3.5.

Setting the Baud Rate

●4800 ●9600

●19200 ●38400

●115200

Select the desired baud rate in the Baud Rate field.

Selecting Handshake

●XON/XOFF

●Hardwired

Select the desired type of handshake in the Handshake field.

Fig.3.5 The Printer Interface Window

Chapter 3 – System Menu

System Menu

BB1119 – 11 3–7

2238 Mediator

User Manual

3.1.7 Choosing the Language

The language used in the instrument’s display screen can be

changed in the Language Window, as illustrated in Fig.3.6.

The following languages can be selected

●English ●Francais

●Deutsch ●Italiano

●Espanol

3.1.8 Adjusting the Display Contrast

You can adjust the LCD screens contrast in the Display

Window (see Fig.3.7), to compensate for various lighting con-

ditions and viewing angles. The contrast adjustment is par-

ticularly useful in very high or low temperature

environments.

Fig.3.6 The Language Window

Fig.3.7 The Display Window

Chapter 3 – System Menu

System Menu

3–8 Brüel & Kjær2238 Mediator

User Manual

Contrast Adjust

●1 5

You can adjust the contrast in five steps, where 5 indicates

the highest contrast level. The default setting is 3.

3.1.9 Displaying the International Standards

The Standards Window in Fig. 3.8 shows the international

standards that Mediator complies with.

3.1.10 Displaying System Information

The About System Window is shown in Fig. 3.9 and contains

the following information:

●Current application module (type)

●Mediator serial number

●Microphone serial number (supplied microphone)

●Filter set

Fig.3.8 The Standards Window

Fig.3.9 The About System Window

BB1119 – 11 4–1

2238 Mediator

User Manual

Chapter 4

Measurement Set-up Menu

4.1 Measurement Set-up Menu ............................................ 4–2

Introduction ....................................................................... 4 – 2

Selecting the Measurement Set-up Menu

and Parameters ................................................................. 4 – 2

Setting up General Measurement Parameters................ 4 – 3

Setting Frequency Weightings ......................................... 4 – 5

Measurement Control ....................................................... 4 – 6

Selecting Correction Filters .............................................. 4 – 7

Setting up the Input/Output Function............................. 4 – 8

Setting Mediator to Start Automatically ......................... 4 – 9

Setting the Occupational Health Parameters................ 4– 11

Saving Measurement Set-ups......................................... 4 – 12

Recalling Measurement Set-ups..................................... 4 – 13

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

4–2 Brüel & Kjær2238 Mediator

User Manual

4.1 Measurement Set-up Menu

4.1.1 Introduction

This chapter explains how to set up basic measurement pa-

rameters in the Measurement Set-up menu, such as range

and weighting.

4.1.2 Selecting the Measurement Set-up Menu and

Parameters

The Measurement Set-up menu is used for setting up basic

measurement parameters and measurement control parame-

ters. Basic SLM Software BZ 7126 contains the menu items

shown in Fig. 4.1.

1. The Set-up menu is accessed by pressing the System

key when the instrument is paused. If the instrument is

measuring you must press to pause. Select the de-

sired menu item with the cursor keys.

This will also cause the <Select> and <Close> soft keys

to appear.

2. Press the <Select> softkey or the cursor key

to enter the selection.

This will also cause the <Ok> and <Cancel> soft keys to

appear.

Fig.4.1 The Measurement Set-up menu (two windows)

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

BB1119 – 11 4–3

2238 Mediator

User Manual

Alternatively you can step through the menu items by press-

ing the Set-up key repeatedly. The first time you press the

key the Set-up menu is displayed and the following key clicks

steps you directly through the menu items, starting with the

first item in the menu.

The arrows on the left-hand side of some of the screen indicate

that there is more than one screen page. These pages are

cyclic, i.e., when you pass the top or the bottom line of the

menu you automatically go the bottom or top line of the next/

previous page, respectively.

4.1.3 Setting up General Measurement Parameters

The General Window is used for setting up the measurement

range, the peaks over indication and the second exchange

rate, see Fig. 4.2.

Measurement Range

In Range you can select the following default measurement

ranges:

●0 to 80 dB ●10 to 90 dB

●20 to 100 dB ●30 to 110 dB

●40 to 120 dB ●50 to 130 dB

●60 to 140 dB

Note that the dynamic range is always 80 dB. However, if a

non-standard transducer is used and calibrated, the upper

and lower limits may be offset.

Fig.4.2 The General Window

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

4–4 Brüel & Kjær2238 Mediator

User Manual

The range you choose will depend on the environment in

which you are measuring. It is important to select the meas-

urement range so that the instrument is sensitive enough to

measure all relevant sound, but not so sensitive that it over-

loads. Your measurement will not be accurate if an overload

occurs. See section 2.4 for more information about overloads.

To Set the Measurement Range

Check the current measurement range. It is shown at the

top of the Measurement Window.

Use the quasi-analogue display to decide if you have set the

range correctly. If the display is blank most of the time, then

sound levels are too low; select a lower measurement range.

If the display becomes full and the “Overload” warning ap-

pears under the bar graph, then sound levels are overloading

the instrument; select a higher range.

Alternatively you can access the Range Setting Window di-

rectly by using the key.

Setting the Peaks Over Indication

Peaks Over fixes a level for counting the number of times

this level is exceeded by peak values and registered during

a measurement. Intervals of 1s are used and only one over-

load per period is registered.

The Peaks Over level can be set in 1 dB steps from 0 to

180 dB. The setting is independent of the selected linear

measurement range (see above). The default level is 140 dB.

Note that the first decimal(s) and the last decimal of the

value field are set up independently. Use the cursor

keys to select the desired decimal.

To monitor the Peaks Over value on the screen, select the

#cPeaks field in the Measurement Window.

Setting the Second Exchange Rate

The 2nd Exch. Rate is used for evaluation of hearing risk

and is described in Appendix section 10.1.

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

BB1119 – 11 4–5

2238 Mediator

User Manual

The 3 dB Exchange Rate is always measured. You can select

an additional Exchange Rate of 4 or 5 (dB). The Second

Exchange Rate is used for measuring averaged sound levels

with 4 dB (LDOD) or 5 dB (LOSHA) Exchange Rate, respective-

ly. The LXav parameter will change accordingly in the Meas-

urement Window.

4.1.4 Setting Frequency and Time Weightings

The Weightings Window is used for setting up time and

frequency weightings for detector 1 and frequency weightings

for detector 2, see Fig. 4.3.

In the basic version, Detector 1 is RMS and Detector2 is Peak.

Setting Bandwidth and Time Weighting for Detector 1 (RMS)

●Broad-band (F, S, I)

●1/3-octave (F, S, I)

●1/1-octave (F, S, I)

Select the desired option in the Bandwidth field.

Note: The 1/3-octave and 1/1-octave options only ap-

pears when the 1/1-octave and 1/3-octave Filter Set is installed

in Mediator.

Setting Frequency Weighting for Detector 1

●A, C, L (Broad-band)

●31.5 Hz ... 8 kHz (1/1-octave)

Fig.4.3 The Weightings Window

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

4–6 Brüel & Kjær2238 Mediator

User Manual

●20 Hz ... 12.5 kHz (1/3-octave)

Select the desired standardized frequency weighting or centre

frequency in the Freq. Wgt. field. The centre frequencies

depend on the setting in the Bandwidth field.

Setting Frequency Weighting for Detector 2 (Broad-band)

●Peak/C

●Peak/L

You can select the C or L frequency weighting for Detector 2

in the Weighting field.

4.1.5 Measurement Control

The Meas. Control Window is used to set up a preset meas-

urement time and to activate/deactivate it, see Fig. 4.4.

In the Basic module only one measurement can be specified

in the No. of Meas. field (in the Enhanced module you

can specify up to 99 measurements).

When switched On, the Auto Start is started as a normal

measurement, using the key. During an Auto Start you

can control the instrument in the normal way, for example,

you can pause a measurement and resume it.

Fig.4.4 The Measurement Control Window

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

BB1119 – 11 4–7

2238 Mediator

User Manual

Switching the Sequence On/Off

The Sequence field is for switching the measurement se-

quence On or Off. The sequence parameters only appears

when sequence is set to On.

Setting the Preset Measurement Time

Preset Time is for pre-setting the measurement time.

●Hours: Can be set from 0 to 99 in one hour steps

●Minutes: Can be set from 0 to 59 in one minute steps

●Seconds: Can be set from 0 to 59 in one second steps

Note: Minimum measurement time is 30 seconds

4.1.6 Selecting Correction Filters

The Correc. Filters Window in Fig. 4.5 allows you to se-

lect filters to make corrections for sound incidence and wind-

screen influence.

Selecting the Sound Incidence Filter

The Sound Incidence correction can be set to:

●Frontal

●Random

In general Frontal is used for sound with 0° incidence and

Random is used for diffuse sound. In practice the correction

depends on your local standard and the application. Generally

ISO requires Frontal and ANSI requires Random.

Fig.4.5 The Correction Filters Window

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

4–8 Brüel & Kjær2238 Mediator

User Manual

Selecting the Windscreen Correction

The Windscreen Correction can be set to:

●On

●Off

The windscreen filter makes a frequency correction corre-

sponding to the influence of Windscreen UA 0237. With the

correction on, Class1 precision is maintained over the full

frequency range (see specifications).

4.1.7 Setting up the Input/Output Function

The Input/Output Window controls the function of the

Aux1 and Aux2 inputs/outputs. See Fig. 4.6.

In the Basic module Aux 1 is always set to AC output and

Aux2 is always set to DC output.

Selecting Frequency Weighting for Aux 1

In the Freq. Wgt. field you can select:

●Linear

●Det. 1

AC Output supplies the AC output signal to the Aux 1 socket.

Frequency weighting depends on the Freq. Wgt. field (see

below). Full-scale indication corresponds to 1VRMS and the

output is attenuated according to the selected range. This

output signal can be used, for example, for recording the

measured signal on a DAT recorder.

Fig.4.6 The Input/Output Window

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

BB1119 – 11 4–9

2238 Mediator

User Manual

L frequency weighting is used when Linear is selected. When

you select Det. 1, the frequency weighting selected on the

RMS detector is used.

Aux 2

DC Out supplies a DC output signal equivalent to the AC

output signal. It is the time weighted signal (Fast, Inst.) from

detector 1. Full-scale indication corresponds to 4.0V DC

(50 mV/dB).

4.1.8 Setting Mediator to Start Automatically

The Auto Start Window allows you to set up Mediator to

start automatically at any time and date within the next

month. The Auto Start Window is illustrated in Fig. 4.7.

After setting up an Auto Start the Mediator must be switched

off. Then, at the set time, it will switch on, load the specified

set-up, reset and start measuring.

Once the Mediator has started measuring with Auto Start,

you can control it in the normal way. Measurements will

continue until the Mediator is switched off manually or the

batteries run out.

If the Mediator is already switched on at the time it has been

set to automatically start measuring, Auto Start is cancelled

and has no effect. Auto Start does not affect your use of the

Mediator while it is switched on or your current measurement

results.

Fig.4.7 The Auto Start Window

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

4–10 Brüel & Kjær2238 Mediator

User Manual

When the set Auto Start time has passed, Auto Start will be

switched off when you switch off the instrument. This pre-

vents the instrument from repeating an automatic measure-

ment every month.

Selecting an Auto Start

In the Auto Start no. field you can set up up to four dif-

ferent Auto Starts. You must ensure that there are no con-

flicts with other Auto Starts. If two Auto Starts in different

applications are set up to start within the same time span,

the Auto Start that starts first takes priority.

Application

The Application field shows the name of the application

module from which the current Auto Start was created. The

following options exist:

●None

Disables the current Auto Start and indicates that this Auto

Start has not been set up.

●BZ xxxx

Activates the Auto Start and shows the owner status for the

current Auto Start. If the application name is different from

the application module that you are currently using, i.e. if

the Auto Start has been set up with a different application

module, you cannot change the set-up parameters. If you

want to change the owner status for the Auto Start you can

do so by using the cursor keys. When you have

changed the owner status to the current application name

you can change the parameters as desired.

Setting Start Time for an Auto Start

The Date and the Time fields are used for setting up month,

day and time for the current Auto Start. The Mediator will

be automatically switched on shortly (approx. 30 s) before the

set time, so that it is ready for measurement at the specified

time.

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

BB1119 – 11 4–11

2238 Mediator

User Manual

Selecting the Set-up for an Auto Start

With the Use Setup No. field a stored measurement set-up

(1 to 4) can be attached to an Auto Start. When the Auto

Start is executed, the specified measurement set-up is auto-

matically loaded.

4.1.9 Setting the Occupational Health Parameters

You can measure noise dose levels by setting up the param-

eters in the Occupational Health Window, see Fig. 4.8.

The Mediator can measure A-, C- or Lin.-weighted dose levels

with Exchange rates of 3 dB (Leq) and 4 or 5 dB (Lav) levels

with A- and C-weighting. Select the desired dose parameter

in the Measurement Window. The Leq value (with exchange

rate of 3) is always measured. Lav is measured simultaneous-

ly, but before measurement you must select exchange rate of

4 or 5dB in the General Window. Note that the 4 or 5dB

Lav parameters are measured with F or S time weighting.

The dose level represents the amount of received sound en-

ergy expressed as a percentage of the daily allowed dose

(100% level).

Setting the Exposure Time

In the Exposure Time field you can set, in hours and min-

utes, the actual time that you are exposed to noise during a

workday. The noise dose calculation is based on the time you

are exposed to the noise (Exposure Time) relative to a nor-

mal 8 hour workday.

Fig.4.8 The Occupational Health Window

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

4–12 Brüel & Kjær2238 Mediator

User Manual

Specifying the Criterion Level

The Criterion Lev. sound level is specified in your local

standard. It is the level of a sound which, continuously ap-

plied for eight hours, results in a 100% criterion exposure.

The calculation of the noise dose level is based on the criterion

level and the exposure time.

Specifying the Threshold Level

The Threshold Lev. level may be specified in your local

standard. Any sound levels below the threshold value do not

contribute to the Dose measurement data. For example, if

you set the threshold value to 80, any sound levels below

80 dB are not taken into consideration by the instrument

when it calculates integrated values (Leq, Lav, Dose).

4.1.10 Saving Measurement Set-ups

You can save up to four measurement set-ups for each appli-

cation package in the Save Setup Window, see Fig.4.9.

When you save a measurement set-up, you save all the pa-

rameters in the Measurement Set-up menu (see section 4.1.2).

Ensure that these parameters are set up correctly before you

proceed.

Saving the Current Measurement Set-up

●1 – 4

Fig.4.9 The Save Setup Window

Chapter 4 – Measurement Set-up Menu

Measurement Set-up Menu

BB1119 – 11 4–13

2238 Mediator

User Manual

In the Save in no. field, select the number which you want

to save the current set-up as. The selected set-up is saved

when you press the <Ok> Softkey.

4.1.11 Recalling Measurement Set-ups

Measurement set-ups are recalled in the Recall Setup Win-

dow, see Fig.4.10.

When you recall a measurement set-up, you recall all the

parameters listed under Recalling Measurement Set-ups

above.

Recalling a Measurement Set-up

●1 – 4

●Default

From the Recall from no. field you can recall a stored set-

up by entering the desired set-up number. The stored set-ups

are identified by the date they were saved. The date for a

stored set-up appears in the bottom line. You can also recall

the factory default set-up. Refer to section 10.2 in Appendix

1 for a list of default parameters. The selected set-up is

recalled when you press the <Ok> Softkey.

Fig.4.10 The Recall Setup Window

4–14 Brüel & Kjær2238 Mediator

User Manual

BB1119 – 11 5–1

2238 Mediator

User Manual

Chapter 5

Measuring

5.1 Calibrating.............................................................................. 5–2

Introduction ....................................................................... 5 – 2

Calibrating the Mediator .................................................. 5 – 3

Checking the Calibration.................................................. 5 – 7

Calibration History ........................................................... 5 – 7

5.2 Starting a New Measurement ....................................... 5 – 8

5.3 Pausing a Measurement .................................................. 5 – 9

5.4 Continuing a Measurement............................................ 5 – 9

5.5 Measuring in 1/1- and 1/3-octave bands ................... 5 – 10

5.6 Setting the Mediator to Start Automatically ....... 5 – 10

5.7 Changing Displayed Measurement Parameters.5–11

Chapter 5 – Measuring

Calibrating

5–2 Brüel & Kjær2238 Mediator

User Manual

5.1 Calibrating

5.1.1 Introduction

When to Calibrate

The standards recommend that you calibrate your sound level

meter before each set of measurements (see section 5.1.2) and

check the calibration after each set (see section 5.1.3).

Connecting a recommended microphone extension cable (see

section 2.2.5) has no effect on Mediator’s calibration. There-

fore, you do not have to recalibrate after connecting one of

the recommended microphone extension cables.

Principle of Calibration

Mediator uses a sensitivity value to check for drift. This is

shown in the Calibration Window. When calibrating, Me-

diator first checks the calibration signal against the calibra-

tion level you have specified. It shows you the new sensitivity

value required for correct calibration, the current (previous)

and the initial (factory) sensitivity values and asks if you

want to recalibrate. If you press <Accept>, Mediator cali-

brates itself according to this new calibration level (i.e. it

adjusts the sensitivity according to the calibration level.

During this procedure, Mediator is automatically set to use

the reference measurement range and settings. To ensure

that a calibration is valid, Mediator compares the output from

both detectors during calibration. It also ensures that the

calibration level is stable during calibration. The maximum

allowed standard deviation is 0.1dB over a 4 second period.

Calibrating for Free-field or Diffuse Field Measurements

The sound level meter is calibrated in the same way for free-

field measurements (according to IEC) and diffuse field meas-

urements (according to ANSI). However, the calibration levels

for some calibrators may be different, depending on which

measurements are to be made. See the calibrator’s user man-

ual for more details. The correction filters are automatically

Chapter 5 – Measuring

Calibrating

BB1119 – 11 5–3

2238 Mediator

User Manual

set to Frontal and Windscreen Off during calibration. Af-

ter calibration they return to the previous settings.

Which Calibrators Can I Use?

Mediator is normally used with the supplied microphone Type

4188. The initial (factory) calibration is performed with the

microphone supplied with Mediator. However, an unspecified

transducer, e.g. another microphone or a hydrophone may be

used. In principle, since you specify the calibration level, any

calibration level in the range 50 to 200dB can be used, de-

pending on the transducer.

Microphones are usually calibrated at 94, 114 or 124 dB. The

default value for Mediator is 94.0dB. Sound Level Calibrator

Type 4231 provides 94 or 114 dB SPL at 1 kHz. Multifunction

Acoustic Calibrator Type 4226 provides 94, 104 or 114dB

SPL. Hydrophone Calibrator Type 4229 generates 151 to

166 dB re 1µPa at 250Hz.

Each calibrator is slightly different. The actual calibration

level is not necessarily equal to the nominal calibration level.

It is, therefore, important to set the calibration level to the

one given on the calibration chart for the calibrator used.

5.1.2 Calibrating the Mediator

For day to day calibration, you only need to calibrate at one

level at one frequency. In order to comply with the standards,

calibrate the sound level meter with a reference signal of

94 dB* at 1 kHz.

To calibrate with microphone Type 4188:

1. Switch on the Mediator and press the Calibrate key.

Select Calibration from the Calibration menu, see

Fig. 5.2.

* When using Type 4231 set the calibration level to 93.9dB for free-field calibration ac-

cording to IEC standards. For pressure calibration according to ANSI standards, set the

level to 94.0 dB.

Chapter 5 – Measuring

Calibrating

5–4 Brüel & Kjær2238 Mediator

User Manual

The Current Calibration Window appears as shown in

Fig. 5.3.

Fig.5.1 Fitting Sound Level Calibrator Type 4231 onto the Mediator.

Multifunction Acoustic Calibrator Type 4226 is fitted in a simi-

lar way (see its manual)

Chapter 5 – Measuring

Calibrating

BB1119 – 11 5–5

2238 Mediator

User Manual

●Microphone — shows the serial number for the Type

4188 supplied with the Mediator or if an unspecified

transducer has been used for the calibration

●Calibration Level — the calibration level that was

specified for the current calibration. The

Calibration Level must be within 50 to 200dB and

can be stepped in 1 and 0.1 dB steps. The default value

is 94.0dB

●Sensitivity — the sensitivity value calculated by

Mediator as a result of the current calibration. You

cannot access this field

●Date — the date for the current calibration. You can-

not access this field

2. Check that microphone Type 4188 is selected and that

the calibration Level is set to 94.0 dB (or the calibration

level specified on the calibrators calibration chart).

3. Press Calib. and Fit the calibrator carefully onto the

sound level meter and rest the sound level meter on a

table or other flat surface. Ensure that the calibrator fits

snugly on the microphone (see Fig.5.1).

Fig.5.2 The Calibration menu

Fig.5.3 The Current Calibration Window

Chapter 5 – Measuring

Calibrating

5–6 Brüel & Kjær2238 Mediator

User Manual

4. For the multifunction acoustic calibrator, set it up to

calibrate at 94dB and 1 kHz (see the calibrator’s instruc-

tion manual).

5. Switch on the calibrator.

The calibrator emits a 1 kHz calibration signal.

6. Press Start and wait until the calibration is finished.

If the calibration is successful the Calibration Result

Window will appear as shown in Fig. 5.4.

●Calibration Level — the calibration level you have

specified

●New Sens. — the new sensitivity value calculated by

Mediator as a result of the calibration

●Current Sens. — the current sensitivity value that

is valid until you press the Accept key. Comparing

the New Sens. and the Current Sens. values gives

you the option to evaluate the relative deviation since

the last calibration

●Initial Sens. — the factory sensitivity value. Al-

lows you to evaluate the absolute deviation since the

instrument was manufactured. If the New Sens. val-

ue deviates more than ±1.5 dB from the

Initial Sens. value, an error message will appear

7. Press Accept if the New Sens. value is within accept-

able limits. The New Sens. value is implemented.

Fig.5.4 The Calibration Result Window

Chapter 5 – Measuring

Calibrating

BB1119 – 11 5–7

2238 Mediator

User Manual

Press Cancel if you cannot accept the New Sens. value.

A new calibration must be performed. This also applies

if the Calibration Error warning appears.

●Check that the microphone has been fitted properly

●Check that the calibrator has been switched on and

is working properly

●Check that the Calibration Level has been entered

correctly

●External noise or vibrations may have affected the

calibration

●Inspect the microphone to see if it has been damaged

5.1.3 Checking the Calibration

Follow the instructions given in section 5.1.2 until item 8. If

the New Sens. value is similar to the Current Sens. value

press the Cancel key to return to the main screen. Otherwise

a recalibration is required.

5.1.4 Calibration History

Select Calibration History from the Calibration menu.

The Calibration History Window will appear as shown

in Fig. 5.5.

The first line in the Calibration History Window always

shows the initial (factory) calibration sensitivity and the se-

rial number for the supplied microphone. In addition the

Fig.5.5 The Calibration History Window

Chapter 5 – Measuring

Starting a New Measurement

5–8 Brüel & Kjær2238 Mediator

User Manual

Calibration History Window contains information about

the 20 latest calibrations. The following information is stored:

●Date — year, month and day for the calibration

●Sens. — the calculated sensitivity for the calibration

●Mic. — indicates whether the calibration was per-

formed with the supplied 4188 microphone (serial

number) or with an unspecified transducer (Unspec.)

Press Print if you want to print out the calibration history

list.

5.2 Starting a New Measurement

1. Switch on the Mediator.

●If another application program has been used, select

the Basic SLM software from the System menu. Nor-

mally you do not need to change any parameters in

the System menu (see section 4.1).

2. Calibrate the sound level meter as described in section

5.1.2.

3. Set up the parameters in the Measurement Setting menu,

as described in section 4.1.2. Normally you will only need

to:

●Select a suitable measurement range. This reduces

the risk of you having to change the range during a

measurement in order to avoid overloads. Overloads

reduce the validity of your results and changing the

measurement range causes a reset.

●If you want to measure according to IEC standards

(i.e. free-field), set Sound Incidence to Frontal in

the Correction Filters Window and simply point

the sound level meter towards the sound source.

●If you want to measure according to ANSI standards

(i.e. diffuse-field), set Sound Incidence to Random in

Chapter 5 – Measuring

Pausing a Measurement

BB1119 – 11 5–9

2238 Mediator

User Manual

the Correction Filters Window. The direction of

the sound level meter is unimportant. If, however, the

sound field is free, measure with the sound level meter

at an angle of between 70 and 80° to the sound source.

●Select the desired measurement parameters in the

Measurement Window.

4. Press . The sound level meter starts measuring with

the selected set-up.

Note: If you want to delete the measured data and set the

buffer and timer to zero, press . If the measurement has

been in progress for more than one minute, a warning is

displayed and you must confirm that data is to be deleted.

5.3 Pausing a Measurement

The Pause mode of the Mediator allows you to store results

in its memory or transfer results across the interface to a

printer or computer.

Press . The Pause symbol appears in the upper left-

hand corner of the display. The clock stops counting the meas-

urement time. The display and quasi-analogue scale continue

to show the current status of the displayed parameters and

input signal level, respectively. In Pause mode, however, no

results or overload indications are added to the buffer.

5.4 Continuing a Measurement

Press . The Measurement symbol is shown instead of

the Pause symbol.

The clock continues counting the measurement time from the

point at which it stopped. Results are added to the buffer.

Chapter 5 – Measuring

Measuring in 1/1- and 1/3-octave bands

5–10 Brüel & Kjær2238 Mediator

User Manual

5.5 Measuring in 1/1- and 1/3-octave

bands*

Follow the instructions below to perform 1/1- and 1/3-octave

band measurements.

1. Select 1/3-octave or 1/1-octave in the Bandwidth

field as required (see section 4.1.4).

2. Select the centre frequency of the band in which you want

to start the analysis, in the Freq. Wgt. field in the

Weightings Window.

3. After you have completed the measurement in that fre-

quency band, press .

4. Store the measurement result in a file (see section 6.3).

5. Select the centre frequency of the band in which you want

to continue the analysis. You are now ready to measure

in the next frequency band.

6. Repeat steps 3 to 5 for the other bands in which you

want to measure.

For automatic frequency analysis measurements Frequency

Analysis Software BZ 7123 is recommended. It is, however,

possible to make a frequency analysis as a series of meas-

urements in various frequency bands, as explained above.

5.6 Setting the Mediator to Start

Automatically

The Mediator can be set to automatically start at any time

and date within the next month (for example from 19th May

to 18th June). To set up an Auto Start, refer to section 4.1.8.

*Only available with Mediator 2238–A–F (version with filter set installed)

Chapter 5 – Measuring

Changing Displayed Measurement Parameters

BB1119 – 11 5–11

2238 Mediator

User Manual

5.7 Changing Displayed Measurement

Parameters

The parameters available are listed in section 1.3. The se-

lected parameters and the measurement values are shown at

the bottom of the Measurement Window.

After a Reset, “– – –.–” is shown for all integrated values

until after the first second. Instantaneous (and SPL) values

are displayed continuously. This is because the levels are not

yet available. Some of the averaged values take even longer,

depending on the averaging times. When pressing Pause

all values are displayed continuously. The Bar Graph always

shows the current SPL level (LXYinst), regardless of the se-

lected parameters.

The parameters can be changed while a measurement is in

progress.

1. Use the cursor key to go to the desired parameter

line in the Measurement Window.

2. Select the desired measurement parameter with the

cursor keys.

3. Return to the basic Measurement Window with the

cursor keys.

When the time or frequency weightings or the exchange rate

are changed, the associated measurement parameters in the

Measurement Window are automatically changed and the

counter is reset.

Note: If the measurement has been in progress for more than

one minute, a warning is displayed and you must confirm

that data is to be deleted.

5–12 Brüel & Kjær2238 Mediator

User Manual

BB1119 – 11 6–1

2238 Mediator

User Manual

Chapter 6

Data Handling

6.1 Data File System................................................................. 6–2

Saved Data......................................................................... 6 – 3

Set-up Data........................................................................ 6 – 3

Measurement Data............................................................ 6 – 4

6.2 Selecting the Data Files Menu...................................... 6 – 4

6.3 Store Files............................................................................... 6 – 5

6.4 Print Options......................................................................... 6 – 5

6.5 Print........................................................................................... 6 – 7

6.6 File Manager ......................................................................... 6 – 7

Recall Files......................................................................... 6 – 8

Print ................................................................................... 6 – 9

Delete ................................................................................. 6 – 9

Delete All ........................................................................... 6 – 9

Disk Summary................................................................. 6 – 10

Chapter 6 – Data Handling

Data File System

6–2 Brüel & Kjær2238 Mediator

User Manual

6.1 Data File System

A total of 2000 data files of measurement results can be

stored in memory. However, you can only store up to 500 files

for each software package. Data files are copied from the

buffer. All records are preserved when you turn off the in-

strument, except for the data in the buffer. Measurements

can be stored automatically (during an Auto Start sequence)

or manually (at any time after a measurement is stopped).

File Names

Measurements are saved in Mediator as files with a file name

that consists of file number and an extension. In addition the

files can be identified by the date and time when the file was

saved.

Example:

001.M26 YYMMDD TTMMSS

File name: Consists of a three digit number from 000 to 500.

Number 000 is used for back-up purposes, for example, in a

power-down situation with flat batteries, the content of the

buffer is saved in no. 000. File numbers are generated auto-

matically as consecutive numbers.

Extension: The following extensions are used to identify the

software package in which the files were made. The two digits

in the extension correspond to the last digits in the type

number:

M26: Basic SLM Software BZ 7126

M25: Enhanced SLM Software BZ 7125

M23: Frequency Analysis Software BZ7123

M24: Logging SLM Software BZ 7124

ID: The date and time (YYMMDD TTMMSS) information is

used to identify the files.

Chapter 6– Data Handling

Data File System

BB1119 – 11 6–3

2238 Mediator

User Manual

6.1.1 Saved Data

A basic measurement data file consists of a group of set-up

data and a group of associated measurement data. The set-

up data are:

●Serial number for the Mediator

●Measurement set-up

●Calibration data

●Measurement data

Measurement data are:

●Overall results

●RMS Broadband data

●Broad-band Peak data

6.1.2 Set-up Data

Measurement Set-up

All measurement set-up parameters that was used for the

measurement.

Calibration Set-up (for individual measurements)

●Microphone type

●Sensitivity

●Calibration date

6.1.3 Measurement Data

Overall Results

●Start date

●Start time

●Elapsed time

Chapter 6 – Data Handling

Selecting the Data Files Menu

6–4 Brüel & Kjær2238 Mediator

User Manual

●Overload

●Under-range

Broadband Data for Detector 1

LFMax, LSMax, LIMax, LFMin, LSMin, LIMin, Leq, LIeq, LAep,d,

LAE, EA, LFav4, LSav4, Dose, FDoseX, SDoseX, AUX1, AUX2

Note: Only the parameters with the selected time weighting

are saved.

Peak Data for Detector 2

●Number of peaks

●LXpkMax

6.2 Selecting the Data Files Menu

The Data Files menu is used for saving and printing files

and for accessing the File Manager. It contains the menu

items shown in Fig. 6.1.

1. The Data Files Window is accessed by pressing the

Data Files key when the instrument is paused. If the

instrument is measuring you must press to pause.

Select the desired menu item with the cursor

keys.

This will also cause the <Select> and <Close> soft keys

to appear.

Fig.6.1 The Data Files Window

Chapter 6– Data Handling

Store Files

BB1119 – 11 6–5

2238 Mediator

User Manual

2. Press the <Select> softkey to enter the selection.

This will also cause the <Ok> and <Cancel> soft keys to

appear.

6.3 Store Files

Automatically Saved Files

Measurements that are made with at preset measurement

time are stored automatically with consecutive numbers.

If the Mediator switches off because of flat batteries, the

content of the buffer is saved in file no. 000.

How to Store the Current Measurement Manually

1. Press the Pause/Continue key to pause the meas-

urement.

2. Press the Data Files key to display the Data Files

menu.

3. Press the <Select> softkey or the cursor key

to store the measurement with the displayed file name.

A “Saving File ...” message is displayed while saving

takes place.

6.4 Print Options

Before you print a file or the contents of the buffer, you should

select which measurement parameters you want to print out.

The Print Options list applies to both the Print function

for the buffer as well as the Print function in the File

Manager.

Setting the Print Options

1. Select Print Options from the Data Files menu.

Chapter 6 – Data Handling

6–6 Brüel & Kjær2238 Mediator

User Manual

2. Use the cursor keys to tag the parameters that you want

to print out. Use the cursor keys to tag (+) or

untag a long list of parameters. Note that parameters

that are already tagged will be de-selected. If you only

want to tag or untag a few parameters, select the desired

parameter with the cursor keys and tag or untag

with the cursor keys. The following parameters

can be printed:

●LMAX

●LMIN

●LAFTm5

●Leq

●LIeq

●LAep,d

●LAE

●EA

●Lav4

●Dose

●Dose4

●#Peaks

●Lpkmax

3. Press <Close> when you have tagged the desired

parameters.

6.5 Print

Simply select the Print option when you have connected the

printer (refer to section 7.1) and set up the desired parame-

ters in Print Options (see above). A “Printing ...” mes-

sage is displayed while the print file is being transferred.

Chapter 6– Data Handling

File Manager

BB1119 – 11 6–7

2238 Mediator

User Manual

6.6 File Manager

The File Manager is used to give an overview of the data

files in the memory and has options for recalling, printing

and deleting these files. The Disk Summary option shows the

memory status.

File List

When you select the File Manager option from the Data

Files menu, you get at file list similar to the first screen

picture illustrated in Fig. 6.2. A file is identified by the file

name and extension and the date and time it was saved.

Pressing the Data Files key when the File List is dis-

played will show the file sizes instead of the dates. A single

file in the Basic module take up approximately 1kbyte of

memory.

Tagging Files

Use the cursor keys to tag the files that you want to select.

Use the cursor keys to tag (+) or untag a long list of

files. Note that files that are already tagged will be de-se-

lected. If you only want to tag or untag a few parameters,

select the desired parameter with the cursor keys

and tag or untag with the cursor keys.

Note: Whenever you leave the File Manager all file tags

will be deleted.

Fig.6.2 The File List in the File Manager menu. The list is shown with

both dates and file sizes

Chapter 6 – Data Handling

File Manager

6–8 Brüel & Kjær2238 Mediator

User Manual

Press the <Menu> softkey to show the options in the

File Manager Options Window, see Fig. 6.3.

6.6.1 Recall Files

Select Recall from the File Manager Options Window to

recall all the tagged files from the File List.

The Recall Files Window contains the same parameter

fields as the Measurement Window (except for instantaneous

values). The Bar Graph is replaced with a File Number field.

When the basic Recall Files Window is selected, you can

scroll through the recalled files by using the cursor

keys. The <Print> option will print the currently recalled file

with the parameters from the Print Options list.

6.6.2 Print

Select Print from the File Manager Options Window to

print all the tagged files from the File List. The Print Win-

dow will appear to show which file is currently being printed.

Fig.6.3 The File Manager Options Window

Fig.6.4 The Recall Files Window

Chapter 6– Data Handling

File Manager

BB1119 – 11 6–9

2238 Mediator

User Manual

6.6.3 Delete

Select Delete from the File Manager Options Window to

delete all the tagged files from the File List. A delete prompt

will appear to confirm that you want to delete the selected

files. The File List will appear to show the remaining files.

6.6.4 Delete All

Similar to the Delete option above, except that all files

(tagged and untagged) will be deleted.

6.6.5 Disk Summary

Select Disk Summary from the File Manager Options

Window to get an overview of the disk memory.

The following parameters are displayed:

●Total: Shows the total disk space in kbytes

●Used: Shows the used disk space in kbytes

Fig.6.5 The Print Window

Fig.6.6 The Delete Window

Chapter 6 – Data Handling

File Manager

6–10 Brüel & Kjær2238 Mediator

User Manual

●Free: Shows the total free disk space in kbytes

●Available: Shows the total number of files that can

still be saved for the current application module

Fig.6.7 The Disk Summary Window

BB1119 – 11 7–1

2238 Mediator

User Manual

Chapter 7

Printing and Transferring Data

7.1 Output to a Printer............................................................. 7–2

7.2 Transferring Data to 7815, 7820, 7821 and 7825.7–2

7.3 Aux 1 and Aux 2 Output ................................................... 7 – 3

Chapter 7 – Printing and Transferring Data

Output to a Printer

7–2 Brüel & Kjær2238 Mediator

User Manual

7.1 Output to a Printer

7.1.1 Setting up for Portable Printer Type 2322

Mediator includes a standard serial port interface. We rec-

ommend using Portable Printer Type 2322 as the printing

format has been optimized for this printer. However, it is

possible to use an IBM Proprinter compatible printer.

Connecting Type 2322

1. Switch off the Mediator and Type 2322 before connecting

the serial interface cable

2. Connect the 9-pin connector on the cable to the 9-pin

Serial Interface socket on the base of Mediator.

3. Carefully tighten the cable’s connector screws to the

screw holes in the sound level meter.

4. Connect the round connector on the cable (arrows facing

upwards) to Type 2322.

Fig.7.1 Location of the serial interface connector

960160e

Serial Interface

Serial interface socket

Aux 1 Aux 2

7-15V

Chapter 7–Printing and Transferring Data

Output to a Printer

BB1119 – 11 7–3

2238 Mediator

User Manual

Setting up Interface Parameters

Ensure that the interface parameters in the

Printer Interface Window are set as follows:

✩Baud Rate: 9600

✩Handshake: XON/XOFF

7.1.2 To Print a Measurement

Connect the printer and set up the interface parameters as

described above. If the printer has not been connected, you

must save the measurement as a file (refer to File Manager

in section 6.6 for printing files) before switching the Mediator

off.

1. Press to pause the measurement.

2. Press the Data Files key to open the Data Files

Window.

3. Select Print from the menu list. A “Printing ...” mes-

sage is displayed while data is transferred to the printer.

Refer to Chapter 6 for details about setting up print options

and printing files.

Measurement Print Format

A Measurement print includes:

1. Header

2. Settings (measurement parameters)

3. Calibration Data (Microphone, Sensitivity and Date)

4. Overall Results (Start Date/Time, Elapsed Time, Over-

load and Underrange)

5. RMS and Peak Measurement Results (selected measure-

ment parameters, see section 6.4)

7–4 Brüel & Kjær2238 Mediator

User Manual

7.1.3 Calibration History

Connect the printer and set up the interface parameters as

described above.

1. Press to pause the measurement.

2. Press the Calibration key.

3. Select Calibration History from the Calibration

menu.

4. Press the Print key to print the Calibration History.

Calibration History Print Format

A Calibration History print includes:

1. Header

2. Calibration History (Date, Time, Sensitivity, Microphone

and Initial Calibration)

7.2 Transferring Data to 7815, 7820,

7821 and 7825

Data export to a PC is normally made to one of the application

programs: 7815 Noise Explorer, 7820/7821 Evaluator or

7825 Protector. The procedure for setting up the interface

is identical for these programs. For installation of the appli-

cation program, refer to the Installation Guide for the respec-

tive program.

1. If the default values have been changed, switch on the

Mediator and set:

✩Baud Rate: 38400

✩Handshake: Hardwired

Refer to section 3.1.5.

Chapter 7–Printing and Transferring Data

Transferring Data to 7815, 7820, 7821 and 7825

BB1119 – 11 7–5

2238 Mediator

User Manual

Note: 38400 is the recommended baud rate. Depending

on your system, a higher baud rate may be possible or a

lower transfer rate may be necessary.

2. Switch off the PC and the Mediator.

Caution: When connecting the Mediator to the PC, en-

sure that both instruments are switched off. Otherwise

they could be damaged.

3. Choose a free COM port on the PC. Normally the COM 1

or COM 2 port. Connect the Mediator to the PC via the

9-pin Serial Interface socket on the base of the Mediator

using cable AO 1386. AO 1386 has 9-pin connectors at

each end. A 9-pin to 25-pin adaptor is supplied with the

cable for use with PC’s with 25-pin serial connectors.

4. Switch on the PC and open the desired application pro-

gram.

5. Select the New Measurement option in the Insert

menu to open the Insert New Measurement Window.

6. Select SLM Type 2238 from the pull-down menu and

click Setup. The Communication Window is displayed.

7. Set the appropriate COM port and Baud Rate parameters

and click OK.

8. Click Next> in the Insert New Measurement Window.

If properly connected, the Mediator is automatically

switched on and measurement file data is transferred to

the application program. Otherwise a Communication

Error prompt is displayed. You must check that the cable

is properly connected and that the interface parameters

are set up correctly.

Note: Disconnect the Mediator from the PC after completion

of data transmission. Leaving it connected risks draining the

batteries because it might power on when the PC is switched

off.

Chapter 7 – Printing and Transferring Data

Aux 1 and Aux 2 Output

7–6 Brüel & Kjær2238 Mediator

User Manual

7.3 Aux 1 and Aux 2 Output

Aux 1

The AC signal emitted from the Aux 1 Output socket is L-

weighted or weighted with the frequency weighting selected

for Detector 1. It can be used for recording noise signals on

tape, transferring signals to an analyser or listening to the

input on headphones.

Aux 2

A DC level corresponding to the instantaneous RMS (Fast)

level is emitted from the Aux 2 socket at the base of the

sound level meter for recording on a plotter.

BB1119 – 11 8–1

2238 Mediator

User Manual

Chapter 8

Maintenance and Repair

8.1 Maintenance and Repair.................................................. 8–2

Care, Cleaning and Storage.............................................. 8 – 2

Chapter 8 – Maintenance and Repair

Maintenance and Repair

8–2 Brüel & Kjær2238 Mediator

User Manual

8.1 Maintenance and Repair

The Mediator is designed and constructed to provide many

years of reliable operation. However, if a fault occurs that

impairs the sound level meter’s correct function, then remove

the batteries to prevent risk of further damage.

For more information about preventing or identifying faults

or damage to your sound level meter, please read the other

sections of this chapter.

For repair, contact your local Brüel & Kjær dealer.

8.1.1 Care, Cleaning and Storage

The Mediator is a precision instrument. When handling, stor-

ing, or cleaning your instrument, please take note of the

following precautions:

Storing the Instrument

●Keep the sound level meter in a dry place

●For long-term storage, remove the batteries

●Do not exceed storage temperature limits of –25 to +60°C

(–13 to +140°F)

Cleaning the Instrument

If the instrument casing becomes dirty, then wipe it with a

cloth lightly dampened with water. Do not use abrasive

cleansers or solvents. Do not allow moisture to enter the

microphone, connectors, or casing.

Handling the instrument

●Do not try to remove the microphone grid, you can easily

damage the microphone in this way

●Do not attempt to open the instrument. There are no

user-serviceable parts inside. If you think your instru-

Chapter 8– Maintenance and Repair

Maintenance and Repair

BB1119 – 11 8–3

2238 Mediator

User Manual

ment requires service, then please contact your

Brüel & Kjær dealer

●Do not allow the instrument to get wet

●Never mix different makes or types of battery

●Never mix new and old batteries

●Do not allow fully discharged batteries to remain inside

the instrument

●Protect the instrument from impact. Do not drop it.

Transport it in the supplied Shoulder Bag (KE0323)

●Avoid large, sudden changes in temperature and humid-

ity. Especially when there is risk of condensation inside

the Mediator, for example, if it is very cold and you

subject it to a hot and humid environment.

8–4 Brüel & Kjær2238 Mediator

User Manual

BB1119 – 11 9–1

2238 Mediator

User Manual

Chapter 9

Specifications

Chapter 9 – Specifications

9–2 Brüel & Kjær2238 Mediator

User Manual

9.1 Specifications

(2238–A and 2238–A–F)

Mediator Type 2238 conforms with both the exist-

ing Sound Level Meter Standards and with the

more comprehensive and more stringent IEC1672

(draft) standard. For the new standard some spec-

ifications are different, and some additional spec-

ifications are required

The different/additional specifications can be found

in section 9.3

General Specifications:

Specifications apply to the 2238 Mediator fitted

with the supplied microphone and preamplifier and

running Basic SLM Software (supplied with each

2238 Mediator)

Note: All references to 1/3-octave bands or 1/1-

octave bands apply only to the Type 2238 –A–F.

Standards:

Conforms with the following:

• EN60651/IEC651 (1979) Type 1 plus Amend-

ment 1

• EN60804/IEC804 (1985) Type 1 plus Amend-

ment 2

• Draft IEC1672/EN 61672 — March 1998,

Class 1

• ANSIS1.4 (1983) Type S 1

• ANSIS1.43–199X Type 1 (Draft 1993)

Supplied Microphone:

Type 4188 Prepolarized Free-field 1/2″ Condenser

Microphone

Nominal Sensitivity: –30dB re 1V/Pa or

31.6 mV/Pa

Capacitance: 12 pF (at 250Hz)

Supplied Microphone

Preamplifier:

ZC0030

Input Impedance: 10 GΩ||0.2 pF

Extension Cables: Available in lengths of 3m and

10 m. No recalibration is required

Measuring Range:

At 1kHz, the difference between the nominal up-

per boundary level on the least sensitive level

range and the lowest sound pressure level meas-

urable on the most sensitive level range.

A-weighted: 25 to 140 dB

C-weighted: 27 to 140 dB

Lin.: 33 to 140 dB

Linear Operating Ranges (worst Case A-

weighted):

For the individual level ranges, at 1kHz, the nom-

inal upper boundary levels minus the lowest sound

pressure level measurable with a noise margin of

5 dB.

With a Microphone Type 4188 of nominal sensi-

tivity:

Inherent Noise level:

Inherent noise is the combination of the electrical

noise and the thermal noise from the microphone

at 20°C. Typical values with supplied microphone

of nominal sensitivity (in dB) are given in the table

below and in Fig.9.1 and Fig.9.2:

Primary Indicator Range:

The upper limit of each Primary Indicator Range

is the same as the upper limit for CF (crest factor)

= 10 of each range setting. The lower limit is either

the upper limit –80dB or one of the following val-

ues, whichever is highest

Upper

limit

Lower

limit

Max. peak

level

Upper limit

(CF = 10)

140 dB 60 dB 143 dB 123 dB

130 dB 50 dB 133 dB 113 dB

120 dB 40 dB 123 dB 103 dB

110 dB 30 dB 113 dB 93 dB

100 dB 25 dB 103 dB 83 dB

90 dB 25 dB 93 dB 73 dB

80 dB 25 dB 83 dB 63 dB

Weighting Electrical

noise

(2238)

Thermal

noise

(4188)

Combine

d Noise

"A" 14 14.5 17.4

"C" 17 13.2 18.5

Lin. 5 Hz–

20 kHz 22 14.2 23

Linear C-weighted A-weighted

38 dB 32 dB 30 dB

Chapter 9– Specifications

BB1119 – 11 9–3

2238 Mediator

User Manual

Indicator Range:

0 to –80 dB relative to upper limit for each range

setting

Frequency Weighting:

Fig. 9.3 shows the curves for the A, C and L fre-

quency weightings The microphone response is

not included

Resolution:

Discrete parameters: 0.1 dB

Broad-band Statistics: 0.5 dB

Detectors:

Simultaneous detection of RMS and Peak with

independent frequency weightings

RMS Detectors

Time Weighting: The RMS detector facilitates

three exponential time weightings (Fast, Slow, Im-

pulse) according to IEC 651 Type 1 (factory

checked to meet Type 0).

Frequency Weightings: A, C or L (also 1/1 and

1/3-octave bands with 2238– A –F)

Tone Burst Response: See Fig. 9.4

Peak detector:

L-weighting: Conforms to IEC 651 and IEC 1672

C-weighing: Conforms to IEC 1672

Rise Time <100 µs (L-weighting)

Overload detector

Monitors all signal paths

Frequency Response:

The effect of the Mediator's casing on the frequen-

cy response is shown in Fig. 9.5. The frequency

and directional responses of the Mediator are

shown in Fig. 9.6, Fig. 9.7and Fig. 9.8)

Measurements:

The available measurement parameters are listed

in the table. RMS and Peak measurements run in

parallel with individual frequency weightings

Symbol Key (for measurement

parameters):

X: Frequency weighting A, C or L

V: Frequency weighting C or L

Y: Time weighting F, S or I

Measurement Control:

Manual control, or pre-set measurement time in

the range 30s to 99 h, 59m, 59s with automatic

storage of measurement

Auto Start:

The Mediator supports four Auto Starts which al-

low set-up of measurement start times up to a

month in advance

Reference Conditions for

Acoustic Calibration:

Using Sound Level Calibrator Type 4231 or Multi-

function Acoustic Calibrator Type 4226

Type of Sound Field: Free-field

Reference Direction of Sound Incidence:

Frontal, perpendicular to microphone diaphragm.

Reference Sound Pressure Level: 94dB

Reference Frequency: 1kHz

Reference Temperature: +20°C (+68°F)

Reference Measuring Level Range: 50–130dB

(automatically set during calibration sequence)

Calibration Correction with Extension Cable:

0dB

Stored Instantaneous

(display only)

LXeq LXYp

LXYav4 LXYInst

LXYav5 LVpk

LAE

LAep,d

LXYmax

LXYmin

LXpkmax

Number of Peaks

Dose%A

Dose%AY4

Dose%AY5

Overload%

Underrange%

Elapsed Time

Start Time

Start Date

Time

Chapter 9 – Specifications

9–4 Brüel & Kjær2238 Mediator

User Manual

Calibration History: 20 most recent calibrations.

The initial calibration value is stored for compari-

son with later calibrations

Display:

128 ×64 dot matrix display with backlight

Measurement Display: Range and quasi-ana-

logue bar graph, plus four measurement parame-

ters that can be freely selected from all available

parameters during measurements

Memory:

2 Mbytes. Up to 500 measurement files can be

stored, including time stamp, complete set-up and

calibration data

Serial Printer:

Measurement data can be printed on Portable

Printer Type 2322 or on an IBM Proprinter-com-

patible printer.

Measurement data can be output as a binary file

for post-processing on a PC

Aux 1 Output:

Connector: 2-pin LEMO

AC Output Signal: Range-adjusted AC output, L-

weighted or with the frequency weighting selected

on the RMS detector. Short-circuit protected

Output: 1VRMS corresponding to full-scale indi-

cation

Max. Load: 10 kΩ|| 1 nF

Output Impedance: Typically 100 Ω

Aux 2 Output:

Connector: 2-pin LEMO

DC Output Signal: DC version of signal on RMS

detector 1 (Fast, Inst). Delayed 0.8s. Short-circuit

protected

Output: 0 to 4.0VDC, (50mV/dB)

Update Rate: 160 times per second

Max. Load: 10 kΩ|| 1 nF

Output Impedance: Typically 100 Ω

Clock:

Real-time (calendar)

Serial Input/Output:

Conforms to EIA/TIA 574 (RS– 232), coupled as

Data Terminal Equipment (DTE). Cable (AO 1386)

is supplied with the Mediator

Connector: 9-pin D-type male

Baud Rates: 4800, 9600, 19200, 38400 and

115200

Word Length: 8 bits, no parity, 1 stop bit

Serial Interface:

Handshake: Hardwired, Modem

Printer Interface:

Handshake: XON/XOFF, Hardwired

Settling Time:

From Power On: <10s

Environmental Effects:

Storage Temperature: –25 to +70°C (–13 to

+158°F)

Operating Temperature: –10 to +50°C (14 to

122°F)

Effect of Temperature: <0.5 dB (–10 to +50°C)

Effect of Humidity: <0.5dB for 30% < RH<90 %

(at 40°C, 1kHz)

Batteries:

Four 1.5V LR6/AA alkaline cells

Lifetime (at room temperature): Typically

>10hours. Automatic switch-off when battery volt-

age sinks below threshold, to avoid invalid meas-

urements

Indicator: Warning on display when less than 15

minutes of lifetime is remaining

Internal Back-up Battery: Keeps clock and data

files operating for at least 6 months (typically) if

fully charged. The back-up battery is charged from

the main batteries. Charging time: approx. 10

hours

External DC Power Supply:

Voltage: Regulated 7 to 15 V

Voltage Ripple: < 20mVpeak to peak

Power: Approximately 150 mA at 7 V (approx.

210 mA with filter set)

Centre Pin: Positive

Weight and Dimensions:

460 g (with batteries), 257 ×97×41 mm

Language:

Each instrument is loaded with English, German,

French, Italian and Spanish text. You can select

any of these languages at any time

9.2 Additional Specifications for

2238 – A – F (Version with

Filter Set Installed)

Standards:

Conforms with the following:

Chapter 9– Specifications

BB1119 – 11 9–5

2238 Mediator

User Manual

• EN 61260/IEC 1260 (1995) Octave and 1/3-oc-

tave Bands Class 1

• ANSI S1.11– 1986 Octave and 1/3-octave

Bands, Order 3, Type 1-D. Optional Range

Octave and 1/3-octave Band

Filters:

Conform to IEC 1260 (1995) and ANSI S1.11 –

1986.

Frequency Rating System: Base 10

Reference Attenuation: 0dB

Linear Operating Range: As Indicator range

Nominal Octave Band Centre Frequencies:

31.5 Hz, 63 Hz, 125Hz, 250 Hz, 500Hz, 1kHz,

2kHz, 4kHz, 8kHz

Nominal 1/3-octave Band Centre Frequencies:

20 Hz, 25Hz, 31.5 Hz, 40Hz, 50Hz, 63Hz, 80Hz,

100Hz, 125 Hz, 160Hz, 200Hz, 250Hz, 315Hz,

400Hz, 500Hz, 630Hz, 800Hz, 1kHz, 1.25kHz,

1.6 kHz, 2 kHz, 2.5 kHz, 3.15 kHz, 4kHz, 5 kHz,

6.3 kHz, 8kHz, 10kHz, 12.5kHz

Batteries:

Lifetime (at room temperature): With filter se-

lected: Typically >7 hours

9.3 Specifications According to

IEC 1672 (2238–A and

2238–A–F)

Steady Level Linearity at 1kHz:

This is the nominal upper boundary levels minus

the lowest sound pressure level that can be meas-

ured with maximum 0.3dB unlinearity within a

10 dB step. Unlinearity is due to inherent noise,

which must be at least 13dB below the lower limit.

Inherent noise is the combination of the electrical

noise and the thermal noise from the microphone

at 20°C. See Fig.9.1 and Fig. 9.2.

For any level range, the upper limit is the upper

boundary of the range. The lower limit is either

the upper limit –80 dB, or one of the following

values, whichever is highest:

Peak-C Ranges:

For any range, the upper limit is the upper bound-

ary of the range +3 dB. The lower limit is either

the upper limit –63 dB, or 60dB (LVpk (

V = fre-

quency weighting L or C)), whichever is highest

Range of Integration Time:

Time Averaged Sound Levels and Sound Expo-

sure Levels can be measured over time intervals

ranging from 1s to >10months (month of 31 days)

Inherent Noise:

Typical time averaged sound levels for integration

times of 1 minute are shown in Fig.9.1 and Fig. 9.2

for a Mediator fitted with a microphone Type 4188

of nominal sensitivity and exposed to a very low

sound level.

Broad Band values for Fast and Slow time weight-

ed measurements are:

Test Information:

Microphone Reference Point: 1.3 mm behind the

front of the protection grid.

During test the microphone signal can be substi-

tuted by an electrical signal input to an adapter

WA 0302 (13 pF) which replaces the microphone.

For a calibration factor of 0 dB the relationship

between applied voltage and reading in SPL fol-

lows the table below

Note: Due to stray capacitance an attenuation of

0.6 dB may result with WA 0302

Input Voltage Maximum: 15 Vpeak-peak

EMC

Classification Group: X

Reference Direction for Testing Radio Frequen-

cy Susceptibility: Microphone facing antenna

9.4 Effect of Accessories:

Fig. 9.16, Fig. 9.17 and Fig. 9.18 show the typical

effect of various accessories on the frequency re-

sponse of Mediator

Linear C-weighted A-weighted

41 dB 35 dB 33 dB

Weighting Fast Slow

A<20dB <20dB

C*21 dB 20 dB

Lin*24 dB 23 dB

* Average of 10 readings taken randomly over a

time interval of 1 minute

Applied Voltage 34 mV 6.76 V

SPL 94 dB 140 dB

Chapter 9 – Specifications

9–6 Brüel & Kjær2238 Mediator

User Manual

CE-mark indicates compliance with: EMC Directive.

EMC Emission EN 50081–1: Generic emission standard. Part 1: Residential, commercial and light

industry.

EN 50081–2: Generic emission standard. Part 2: Industrial environment.

CISPR 22: Radio disturbance characteristics of information technology equipment.

Class B Limits.

FCC Rules, Part 15: Complies with the limits for a Class B digital device.

EMC Immunity EN 50082–1: Generic immunity standard. Part 1: Residential, commercial and light

industry. RF immunity implies that sound level indications of 50 dB or greater will

be affected by no more than 0.5dB.

EN 50082–2: Generic immunity standard. Part 2: Industrial environment. RF im-

munity implies that sound level indications of 65 dB or greater will be affected by

no more than 0.5dB.

These levels of immunity are 9dB better than required by IEC1672.

Note: The above conformance is guaranteed only when using the included/optional accessories.

Brüel& Kjær reserves the right to change specifications and accessories without notice

Fig.9.1 The three components of inherent noise in each 1/3-octave band and in the

broad bands A, C and L (5 Hz – 20 kHz)

Noise

Level

(dB)

-5

-10

-15

-20

25 40 63 100 160 250 400 630 1k 2.5k 4k 6.3k 10k A C Lin

Centre Frequency

Electrical Noise

Thermal Noise

Combined Noise

980280

Chapter 9– Specifications

BB1119 – 11 9–7

2238 Mediator

User Manual

Fig.9.2 The three components of inherent noise in each octave band and in the

broad bands A, C and L

Noise

Level

(dB)

-5

-10

-15

31,5 63 125 250

Centre Frequency

500 1000 2000 4000 8000 A C Lin

Electrical Noise

Thermal Noise

Combined Noise

980281

Chapter 9 – Specifications

9–8 Brüel & Kjær2238 Mediator

User Manual

Fig.9.3 Curves for the A and C and L weightings. The curves do not include the

microphone response

Fig.9.4 Curves showing the detector response of Mediator to 4kHz tone bursts of

various durations

10 100 1k 10k

–10

–5

–15 20 50 200 500 2k 5k 20k 50k5

(dB)

Relative Response

980385

Frequency (Hz)

Response

(dB)

-5

-10

-15

-20

-25

-30

-35

-40

0,1 1 10 100 1000

Duration (ms)

Fast

Slow

Impulse

980279e

Chapter 9– Specifications

BB1119 – 11 9–9

2238 Mediator

User Manual

Fig.9.5 Effect of Mediator’s casing on frequency response

Fig.9.6 Free-field frequency response of Mediator fitted with the supplied micro-

phone Type 4188. IEC 651 Type 1 tolerances are also shown

931236/2e

Relative

Response

(dB)

100 1k 10k

– 1 200 500 2k 5k 20k

Frequency (Hz)

Relative Response (dB)

-1

-2

-3

-4

-5

10 100 1000 10000

Frequency (Hz) 980283

20000

Chapter 9 – Specifications

9–10 Brüel & Kjær2238 Mediator

User Manual

Fig.9.7 Random incidence frequency response of Mediator (random incidence filter

selected) fitted with the supplied microphone Type 4188. IEC651 Type 1

tolerances are also shown

Relative Response (dB)

-1

-2

-3

-4

-5

10 100 1000 10000

Frequency (Hz)

20000

980282

Chapter 9– Specifications

BB1119 – 11 9–11

2238 Mediator

User Manual

Fig.9.8 Directional characteristics of the Mediator fitted with the supplied micro-

phone Type 4188. Characteristics measured at 1, 2, 4, 8 and 12.5kHz

980386/1e

330

300

270

240

210

180

150

120

50 30 20 10 0

50 40 30 20 10 0

12.5

kHz

330

300

270

240

210

180

150

120

50 30 20 10 0

50 40 30 20 10 0

8 kHz

330

300

270

240

210

180

150

120

50 30 20 10 0

50 40 30 20 10 0

4 kHz

330

300

270

240

210

180

150

120

50 30 20 10 0

50 40 30 20 10 0

2 kHz

330

300

270

240

210

180

150

120

50 30 20 10 0

50 40 30 20 10 0

1 kHz

Brüel & Kjær 2238 Mediator

7/6-'89

OVL

02:00:00

F MaxL 83·6 dBA

40 .... 120+

5dB

Chapter 9 – Specifications

9–12 Brüel & Kjær2238 Mediator

User Manual

Fig.9.9 Curves showing the shape of the octave-band filters (from 0 to –80dB).

IEC 1260 tolerances are also shown

Fig.9.10 Curves showing the shape of the octave-band filters (from 0 to –3.5 dB).

IEC 1260 tolerances are also shown

Response

(dB)

-10

-20

-30

-40

-50

-60

-70

-80

0,01 0,1 1 10 100

Multiple of Centre Frequency

980289

-1

-2

-3

-4

-5

Multiple of Centre Frequency

Response

(dB)

0,5 2

980286

Chapter 9– Specifications

BB1119 – 11 9–13

2238 Mediator

User Manual

Fig.9.11 Curves showing the shape of the 1/3-octave-band filters (from 0 to –80dB).

IEC 1260 tolerances are also shown

Fig.9.12 Curves showing the shape of the 1/3-octave-band filters (from 0 to –4 dB).

IEC 1260 tolerances are also shown

Response

(dB)

-10

-20

-30

-40

-50

-60

-70

-80

Multiple of Centre Frequency

0,1 110

980288

Response

(dB) 0

-1

-2

-3

-4

0,85 0,9 0,95 1 1,05 1,1 1,15

Multiple of Centre Frequency 980287

Chapter 9 – Specifications

9–14 Brüel & Kjær2238 Mediator

User Manual

Fig.9.13 Maximum sound pressure levels that can be measured within tolerance lim-

its of IEC 1672, A- and C-weighted and L

140

130

120

110

100

1 10 100 1000 10000 100000

980314e

Lin

Chapter 9– Specifications

BB1119 – 11 9–15

2238 Mediator

User Manual

Fig.9.14 Typical variation in frequency response (normalized at 250 Hz) as a func-

tion of change in ambient pressure, relative to 101.3 kPa (Type 4188)

940762e

1k 10k Frequency (Hz)

– 1

Correction (dB)

500 50k

– 10kPa

change

– 20kPa

change

– 40kPa

change

Chapter 9 – Specifications

9–16 Brüel & Kjær2238 Mediator

User Manual

Fig.9.15 Typical variations in frequency response as a function of temperature, rela-

tive to the response at 20°C (Type 4188)

Fig.9.16 Influence of Protective Cover UA 1236 on Mediator's frequency response

940806/1e

Frequency (Hz)1 k 10 k 50 k

1.0

Response (dB)

– 1.5

– 1.0

– 0.5

0.0

0.5

500 Hz

1.5

– 10°C

50°C

931234/1e

Relative

Response

(dB)

100 1k 10k

– 1 200 500 2k 5k 20k

Frequency (Hz)

Chapter 9– Specifications

BB1119 – 11 9–17

2238 Mediator

User Manual

Fig.9.17 Influence of Windscreen UA0237 on Mediator’s frequency response, with

and without the windscreen correction filter

Fig.9.18 Influence on Mediator’s frequency response when mounted on Tripod UA1251

1,0

0,0

-1,0

-2,0

-3,0

Response (dB)

100 1000 10000

Frequency (Hz)

980285

Influence of windscreen

Windscreen with correction filter

100 1k 10k

– 1 200 500 2k 5k 20k

931235/1e

Frequency (Hz)

Relative

Response

(dB)

9–18 Brüel & Kjær2238 Mediator

User Manual

9.5 Accessories Included:

Type 4188: Prepolarized Free-field 1/2″

Condenser Microphone

ZC0030: Microphone Preamplifier

AO1386: 9-pole Cable with 25-pole Adap-

tor (for computer and serial

printer)

KE0323: Shoulder Bag

UA1236: Protective Cover

QB 0013: 4 Alkaline Batteries

9.6 Optional Accessories

AO0560/0409: Microphone Extension Cable

(10 m)

AO0561/0408: Microphone Extension Cable

(3 m)

ZG 0386 Power Supply (European ver-

sion)

ZG 0387 Power Supply (UK version)

ZG 0388 Power Supply (US version)

BB1119 – 11 10 – 1

2238 Mediator

User Manual

Chapter 10

Appendix 1: General

10.1 Exchange Rate.................................................................... 10 – 2

10.2 List of Default Parameters ........................................... 10 – 4

10.3 Interface Errors.................................................................. 10 – 6

10.4 Messages and Warnings................................................. 10 – 8

10.5 Error messages................................................................. 10 – 12

Chapter 10 – Appendix 1: General

Exchange Rate

10–2 Brüel & Kjær2238 Mediator

User Manual

10.1 Exchange Rate

When measuring noise for the evaluation of hearing risk, the

time factor has an important influence.

It is generally assumed that doubling the noise energy also

doubles the hearing risk. This means that if the noise energy

is doubled (i.e. it increases by 3 dB) the allowed exposure time

should be halved.

Thus, as the equal energy concept requires a halving of the

exposure time for a 3 dB increase in level (Leq), it is said to

have an Exchange Rate of 3dB. This is standardized by ISO.

However, in the USA, the OSHA regulation allows a 5dB

increase in level for each halving of the exposure time (i.e.

the Exchange Rate is 5 dB). It therefore uses an Lav with

this Exchange Rate. This Lav5 (or LOSHA) has a different

relationship between level and time than the equal energy

concept standardized by ISO.

This is shown in Fig.10.1. Going from an exposure time of

8 hours to 4hours allows an increase of 3dB in the Leq in

accordance with ISO, but an increase of 5dB in the LAV5 in

accordance with OSHA.

An Exchange Rate of 4 dB also exists (Lav4 or LDOD).

Leq and LEP,d are always measured based on a 3 dB Exchange

Rate. The second Exchange Rate (4 or 5dB) determines

whether Lav4 or Lav5 is measured.

Chapter 10– Appendix 1: General

Exchange Rate

BB1119 – 11 10 – 3

2238 Mediator

User Manual

Fig.10.1 The effect of an Exchange Rate of 3 or 5dB

Exchange Rate (dB) Parameter

eq and Lep,d (always measured)

av,4 (LDOD)

av,5 (LOSHA)

Table 10.1 The LAV parameter measured by the sound level meter is de-

pendent on the Exchange Rate

860884e

OSHA

ISO

100

105

241 8h t

Leq

dB(A)

Chapter 10 – Appendix 1: General

List of Default Parameters

10–4 Brüel & Kjær2238 Mediator

User Manual

10.2 List of Default Parameters

Menu Set-up Parameter Default Value

General

Range 30 – 110 dB

Peaks Over 140dB

2nd Exch. Rate 4 dB

Weightings

Bandwidth (Detector 1) Broad Band

Freq. Wgt. (Detector1) A (“F”)

Weighting (Detector2) Peak

Meas. Control Sequence Off

Corr. Filters Sound Incidence Frontal

Windscreen Filter Off

Input/Output Aux 1 AC Output

Aux2 DC Output

Auto Start Auto Start No. 1

Owner None

Occ. Health

Exposure Time 7:30 (2700 s)

Criterion 100 dB

Threshold 0 dB

Save Setup Save in No. 1

Recall Setup Recall From No. Default

Interface

Baud Rate (printer) 9600

Handshake (printer) XON/XOFF

Baud Rate (remote) 9600

Language English

Chapter 10– Appendix 1: General

Messages and Warnings

BB1119 – 11 10 – 5

2238 Mediator

User Manual

10.3 Messages and Warnings

If you get a message or warning while using or calibrating

your Mediator, then refer to the chart below.

Display Contrast Adjust 2

Message Occurs Solution

When a calibration is

executed Wait until the cali-

bration is finished

When a new

calibration sensitivity

value has been

accepted

Wait until the new

value has been

saved

When a measurement

has been in progress

for more than 1 minute

and you are about to

delete the measure-

ment data if you:

1: Change the meas-

urement range.

2: Make changes to

the measurement set-

up.

3: Make a calibration

Normal situation to

avoid deleting the

measurement.

Press “OK” if meas-

urement data should

be deleted or “Can-

cel” if you want to

continue the meas-

urement

Menu Set-up Parameter Default Value

Performing

calibration check

Please wait

Saving

Please wait

Warning

Measurement will

be reset.

Continue?

Chapter 10 – Appendix 1: General

Messages and Warnings

10–6 Brüel & Kjær2238 Mediator

User Manual

When a measurement

sequence is set up and

the required number of

files for the sequence

exceeds the number

available in memory

Reduce the number

of measurements in

the sequence or

save some of the

files in memory on a

PC.

When a file is being

saved Wait until the file is

saved

When the selected

files are being deleted Wait until the files

have been deleted

Before a number of

selected files are being

deleted

Normal situation to

avoid deleting files

accidentally. Press

“OK” to delete the

files or press “Can-

cel” to skip deleting

the files

When “Delete All” has

been activated and the

files are being deleted

Wait until all the files

have been deleted

Warning

X files needed

Y files available

Continue anyway

Saving file

Deleting selected

file(s) ...

Delete selected

file(s)?

Deleting all

files ...

Chapter 10– Appendix 1: General

Messages and Warnings

BB1119 – 11 10 – 7

2238 Mediator

User Manual

Before all files are

deleted when “Delete

All” has been selected

Normal situation to

avoid deleting files

accidentally. Press

“OK” to delete all

files or press “Can-

cel” to skip deleting

all files

An operation has been

activated that requires

that a number of files

are tagged

Tag the desired files

When “Disk Summary”

in the File Manager

has been selected

Shows an overview

of disk space and

files available

When Print has been

selected in the Data

Files Window or in the

Print Manager. The file

name for the file that is

being printed is shown

in the second line if

Print has been

selected in the File

Manager

Wait until the files

are printed or press

“Cancel” to stop

printing

When a print operation

is cancelled Normal situation

when a print opera-

tion is cancelled

Delete all files?

No tagged files!

To tag files use

left or right arrow

in the file manager

Disk summary

X kbytes total

Y kbytes use

Z kbytes free

Q files available

Printing ...

Cancelling ...

Chapter 10 – Appendix 1: General

Interface Errors

10–8 Brüel & Kjær2238 Mediator

User Manual

10.4 Interface Errors

When the application

module is changed

and measurement

data has not been

saved

Normal situation to

avoid loosing meas-

urement data. Press

“OK” to change

application and

loose data or press

“Cancel” to return to

the current applica-

tion module and

save data

Message Description Number

Header not

found

An unknown header was supplied to

the Mediator 1

Illegal data

type

The current interface message

requires a different data type 2

Parameter error The received interface message was

ambiguous 3

Char data not

found

An unknown character data was

supplied to the Mediator 4

Suffix data not

found

An unknown suffix was supplied to

the Mediator 5

Nr string to

long

The supplied numeric string is too

long 6

Nr out of range The supplied numeric exceeds the

legal range for the data type 7

Non-decimal out

of range

The supplied binary, octal or hex

coded numeric exceeds the legal

range for the data type

Change

application?

Chapter 10– Appendix 1: General

Interface Errors

BB1119 – 11 10 – 9

2238 Mediator

User Manual

String too long The supplied string is too long 9

Block data too

long

The supplied block data exceeds

max length of block 10

Too many

parameters

The supplied interface message

contains more parameters than

allowed

Out of memory System error. Mediator was unable

to allocate enough memory to handle

the interface message used. Use

less complex interface commands

Output is

cancelled

The response to the previous query

message was not read from the

Mediator

Deadlocked The Mediator interface is in a

deadlock condition caused by input

buffer full, parser blocked, response

formatter blocked and output buffer

full. Avoid this by always reading the

response to a query before supplying

the Mediator with new interface

commands. Switch the Mediator off

and on again to exit the deadlocked

condition.

Unexpected byte An unexpected byte was detected

when something else was expected.

For example a space was detected

instead of a message terminator

Unexpected END

detected

An unexpected LF (decimal 10)

message terminator was detected.

For example a “;” or a “+” followed

by LF will cause an interface error

16 because these jobs are not

correctly finished

Message Description Number

Chapter 10 – Appendix 1: General

Interface Errors

10–10 Brüel & Kjær2238 Mediator

User Manual

Interface

overrun

Interface messages were received at

a rate faster than the Mediator can

processes them. This caused an

internal input buffer overrun

Interface

handshake error

An interface handshake error was

detected. Reset the Mediator and try

again

Illegal key

number used

An unspecified key number has been

selected

Setup during

measurement

The set-up cannot be changed while

a measurement is proceeding

No Filter

installed

An octave or 1/3-octave filter has

been specified and no filter set is

installed

Autostart not

applicable

The specified Auto Start is not

allowed. The Auto Start has not been

set up with the current application

module or the date is out of range

File write

error

An error has occurred while storing

data

Illegal value The specified value is out of range

Setup during

measurement

Mediator was in measurement mode

when you tried to change the set-up.

Change to pause mode

No filter

installed

You tried to set up a measurement

parameter that requires the filter set 24

Date out of

range

Normally occurs when the date for

an Auto Start is not valid 25

Message Description Number

Chapter 10– Appendix 1: General

Error messages

BB1119 – 11 10–11

2238 Mediator

User Manual

10.5 Error messages

If you get an error message while using or calibrating your

Mediator, then refer to the chart below.

Auto Start not

applicable

There is an error in the set-up for

the specified Auto Start 26

File write

error

Will not normally occur. The

measurement file is corrupt or the

instrument is defect

Illegal value The specified value is not allowed 28

Message Occurs Solution

During calibration. For

example, if foreign

sounds have corrupted

the calibration signal

or if the calibrator is

not switched on.

Make sure you have

turned on and fitted

the calibrator cor-

rectly. Check the

calibrator’s batter-

ies, and/or move to

a quieter location.

Alternatively use

114dB calibration

level. If the error

persists, then con-

tact your

Brüel& Kjær dealer.

Message Description Number

Calibration error

Unstable input

signal

Chapter 10 – Appendix 1: General

Error messages

10–12 Brüel & Kjær2238 Mediator

User Manual

During calibration, if

the instrument has dis-

covered that the

required calibration

level is more than

±1.5 dB from the fac-

tory calibration (the

“Initial Sens.” value).

Return to the Cali-

bration Window and

enter a calibration

level that is within

the acceptable

range. Make sure

you have selected

the correct calibra-

tion level on your

calibrator. If the error

persists, then you

may need a new

factory calibration.

Contact your

Brüel& Kjær dealer

for assistance.

The output from both-

detectors are com-

pared and the

difference is outside

the acceptable range

Try to calibrate

again. If the error

message persists

your Mediator is

faulty and must be

repaired. Contact

your local

Brüel& Kjær dealer

The calibrator level is

above the maximum

specified dynamic

range (Only with an

unspecified trans-

ducer)

Reduce the calibra-

tion level and per-

form calibration

again

The calibrator level is

below the maximum

specified dynamic

range (Only with an

unspecified trans-

ducer)

Increase the calibra-

tion level and per-

form calibration

again

Message Occurs Solution

Calibration error

New sens. exceeds

acceptance range

±1.5 dB

Detector error!

See error details

in User Manual

Calibration error!

Calibrator level

too high

Calibration error!

Calibrator level

too low

BB1119 – 11 11 – 1

2238 Mediator

User Manual

Chapter 11

Appendix 2: Interface

11.1 Controlling Mediator via the Serial Interface...... 11 – 3

Introduction ..................................................................... 11 – 3

11.2 Formats for Interface Messages ................................. 11 – 4

Terminology for Interface Messages............................... 11 – 4

Use of Syntax Diagrams.................................................. 11 – 6

General Rules for Constructing an Interface Message . 11 – 7

Mnemonic Codes.............................................................. 11 – 8

Message Terminator........................................................ 11 – 9

11.3 Types of Data....................................................................... 11 – 9

11.4 Character Data................................................................. 11 – 10

Numeric Data ................................................................ 11– 10

String Data .................................................................... 11 – 12

11.5 Information Protocol ...................................................... 11 – 13

Introduction ................................................................... 11 – 13

Header............................................................................ 11 – 13

Chapter 11 – Appendix 2: Interface

11–2 Brüel & Kjær2238 Mediator

User Manual

11.6 Setting up the PC............................................................ 11 – 15

Commands..................................................................... 11 – 16

Bandwidth ..................................................................... 11 – 17

Continue......................................................................... 11 – 18

Error? ............................................................................. 11 – 18

File ................................................................................. 11 – 19

Frequency_Weighting_1 ............................................... 11– 23

Frequency_Weighting_2 ............................................... 11– 25

Header............................................................................ 11 – 26

Identify? ......................................................................... 11 – 26

Key ................................................................................. 11– 27

PArameter?.................................................................... 11 – 29

PAUse ............................................................................ 11 – 32

RAnge............................................................................. 11– 32

REset.............................................................................. 11– 34

SEtup ............................................................................. 11 – 34

STatus? .......................................................................... 11– 39

SYstem........................................................................... 11 – 40

Version........................................................................... 11 – 41

Chapter 11– Appendix 2: Interface

Controlling Mediator via the Serial Interface

BB1119 – 11 11 – 3

2238 Mediator

User Manual

11.1 Controlling Mediator via the

Serial Interface

11.1.1 Introduction

This chapter describes the operation of the Mediator via its

serial interface. It assumes that you are familiar with the

manual operation of the sound level meter and have some

interface programming experience.

Echo

All characters sent via the interface to Mediator are echoed

back to the controller, exactly as entered.

Switching on

To avoid accidentally switching Mediator on, the following

procedure must be observed when it is desired to switch the

Mediator on via the interface.

●The baud rate and handshake parameters must be set

to the same for Mediator and the controller (refer to

section 3.1.5)

●The first character that is transmitted will activate the

Mediator

●Within a short period (8 to 10 seconds) the Mediator must

receive more than 4 additional characters to switch on.

If no further characters are received within this period

it will not be switched on. Use the Echo facility to verify

that the Mediator is switched on. Send a character/com-

mand via the interface until the character/command is

echoed back.

Chapter 11 – Appendix 2: Interface

Formats for Interface Messages

11–4 Brüel & Kjær2238 Mediator

User Manual

11.2 Formats for Interface Messages

11.2.1 Terminology for Interface Messages

The data transmitted to and from a Mediator conforms to a

subset of the ANSI/IEEE Standard, IEEE 488.2 (1987), “IEEE

Standard Codes, Formats, Protocols and Common Com-

mands”.

Data that is transferred to or from a Mediator, via the serial

interface, is referred to as a “message”. Two types of message

can be sent to the Mediator, “command” and “query” messag-

es. Messages output by the Mediator replying to a query

message from a controller are referred to as “response” mes-

sages.

Messages to the Mediator

The interface messages are designed according to the ANSI/

IEEE Std 488.2 (1987), “IEEE Standard Codes, Formats, Pro-

tocols and Common Commands”, allowing for compound mes-

sages.

Messages that include both a message header and a message

sub-header are called compound headers. In compound head-

ers, the message header is called the header path or the “root”

header. Interface messages are constructed in a hierarchy in

which some of the messages are “root” messages while other

messages are only defined for a specific message header.

It is always legal to fully specify any message header using

the (:) and the compound header (header path + sub-header),

or “root” header only, if no sub-header is defined for the

message in question. However, since the parser will recognize

only a “root” header after a program message terminator

(<Te> or <LF>), the (:) is not required for the first “root”

header.

Some main rules are:

Chapter 11– Appendix 2: Interface

Formats for Interface Messages

BB1119 – 11 11 – 5

2238 Mediator

User Manual

●Interface messages may be joined together using the Pro-

gram Message Unit Separator (;).

●After a Program Message Terminator (<Te>) the parser

recognizes only “root” headers (this is also the case after

Power Up).

●After reception of a compound header including a header

path and a sub-header, the parser assumes the same

header path until it recognizes either a (:) or a <Te>. This

allows several sub-headers to be joined together with a

(;) using only header path in the first message.

Example:

PArameter:LEq?;LMAx?;LMIn?<Te>

In this example the PArameter command is the “root” head-

er which can be preceded with the optional (:). The LEq?

command following the (:) is a sub-header which can be suc-

ceeded by other sub-headers using the (;) as separator. The

“root” header is active until another (:) is used or the <Te>

command appears:

PArameter:LEq?;LMAx?:Frequency_Weighting_1?:Fre

quency_Weighting_2?<Te>

The (;) following the LEq? query is used to join the two

interface messages, and the (:) following the LMAx? query is

required to change the “root” header.

Example:

:SEtup:N1 10;:SEtup:N2 50;:Setup:N3 90<Te>

When interface messages are joined together using (;), the

“root” header may be omitted for a sequence of interface sub-

headers belonging to the same “root” header as shown in the

following example:

:SEtup:N1 10;N2 50;N3 90<Te>

Chapter 11 – Appendix 2: Interface

Formats for Interface Messages

11–6 Brüel & Kjær2238 Mediator

User Manual

Messages from the Mediator

The structure of the response messages returned by the Me-

diator unit depends on the nature of the query from the

controller. The messages are in minimum code (mnemonics)

or written in full – see section 11.2.4.

11.2.2 Use of Syntax Diagrams

In this manual, syntax diagrams are used to explain the

individual messages. Syntax diagrams use three types of sym-

bol, as illustrated in Fig. 11.1.

Rectangular symbols indicate that the enclosed data must be

replaced by a data item defined elsewhere or chosen by the

user. The name of the data item is quoted in the upper left-

hand corner of the symbol. The type of the data item, and

its allowed length in parentheses are, where appropriate,

given in the lower right-hand corner. Circular symbols enclose

single character literal data that must be included in the

message. Elongated, round-ended symbols indicate literal

word data, such as message headers.

Data items that may be by-passed are indicated by lines to

and from the main flow line. Data items that may be repeated

are indicated by lines that loop vertically from the main flow

line back over the data item and back to the main flow line.

If an item of data is repeated, then the number of repetitions

Fig.11.1 General message syntax

941582e

Data can be bypassed

Te: :

;

Data Field

–

IJKL_MNOPABCD_EFGH

Chapter 11– Appendix 2: Interface

Formats for Interface Messages

BB1119 – 11 11 – 7

2238 Mediator

User Manual

is indicated by a number above the flowline. Flow is from left

to right unless arrows indicate otherwise.

11.2.3 General Rules for Constructing an Interface

Message

The Mediator allows you to input the message headers and

any character type data fields in full. For ease of use, the

data field names correspond to those on the Mediator’s menu

and screen texts wherever possible.

In order to reduce coding and transmission time, mnemonics

can be entered for each of the message components which

use character type data. The mnemonics are derived from the

names of the individual headers or data fields, and their

syntax is the same for headers and character type data fields.

In this manual a message’s minimum allowable mnemonic is

given in bold upper case text, for example

Frequency_Weighting_1:F100. In addition, the following

rules apply:

1. All entries can always be written out in full. For example:

Frequency_Weighting_1:F100

2. Both upper and lower case letters are recognized and are

equivalent:

frequency_WEIGHting_1:f100

3. All headers and character type data fields can be trun-

cated to the mnemonic.

Frequency_Weighting_1:F100

Freq_Wgt_1:F100

F_W_1:F100

4. All mnemonics are unique and consist of one or more

words, with each word consisting of one to three charac-

ters, plus the word concatenators (_).

Chapter 11 – Appendix 2: Interface

Formats for Interface Messages

11–8 Brüel & Kjær2238 Mediator

User Manual

5. When the amplifier receives character type messages, it

checks the entire message. Therefore, any mis-spelled

words are detected as unknown commands.

6. The amplifier returns the full message or only the mne-

monics when transmitting data containing headers and

character type data fields over the bus. This is deter-

mined by the setting of the parameter Header (see section

11.5.2).

7. Between the header and the first data field, a header

separator is entered. The header separator is a space

(SP).

8. Between each of the data fields, the data separator (a

comma <,>) must be entered. See section 11.2.2.

11.2.4 Mnemonic Codes

The following general rules clarify the construction of the

mnemonics (minimum codes). The rules apply for all headers

and data fields which use character type data.

1. If the first letter of every word produces a unique code,

then this is the mnemonic. For example, the header

Frequency_Weighting_1 becomes F_W_1

2. If the first letter of every word does not give a unique

mnemonic, then include two or more characters of one or

more words until the mnemonic is unique. For example,

the message

SETUP_SEQUENCE ON becomes SE_SE ON

SETUP_SEQUENCE OFF becomes SE_SE OF

Notes:

●Word concatenators are always required in mnemonics

which include more than one word, except immediately

before the question mark (?) in an input message header.

Here, the inclusion of the word concatenator is optional.

Chapter 11– Appendix 2: Interface

Types of Data

BB1119 – 11 11 – 9

2238 Mediator

User Manual

●In the tables and syntax diagrams throughout this inter-

face manual, the mnemonics are the characters appearing

in bold within the headers and character type data fields.

●Headers are output either in full or in mnemonic form

by the amplifier.

11.2.5 Message Terminator

The only legal Program Message Terminator character is the

NL (line feed – decimal 10). The <Te> is considered to be a LF.

11.3 Types of Data

A message can contain one or more data fields, or none. The

type of allowed data varies for each message, but the available

types are:

●character data

●numeric data (decimal and integer)

●string data

The data separator used between all data fields is a comma

(,). Fig. Fig. 11.2 shows the general syntax of a message con-

taining all legal data types.

Fig.11.2 General format for a message with all legal data types 941499e

Only for instrument output

Character

Data

Numeric

(Decimal)

Data

Header

;

String

Data

–

Chapter 11 – Appendix 2: Interface

Character Data

11–10 Brüel & Kjær2238 Mediator

User Manual

11.4 Character Data

Character data must begin with an alphabetic character, ei-

ther upper or lower case. This initial alphabetic character

can be followed by any printable ASCII character (from 32

through 127 (decimal)), with the exception of a space (SP), a

comma (,), a semi-colon (;), a colon (:), or the delete character

(DEL). Fig.11.3 shows the valid form of entry for character

data.

All headers and set-up parameter names are character data,

as are many of the parameter settings. In the syntax dia-

grams, character data is represented by “Char.”. When char-

acter data must be included, the data is written out in full

in the syntax diagrams with the mnemonic codes marked as

bold upper-case characters.

11.4.1 Numeric Data

Numeric data that is entered through the interface closely

follows the format defined in the ANSI/IEEE 488.2 (1987)

Standard, “IEEE Standard Codes, Formats, Protocols and

Common Commands” and the ISO 6093–1985 Standard,

“Representation of numerical values in character strings for

information interchange”.

The types of numeric data are represented in the syntax

diagrams by NR1, NR2 and NR3, conforming to the above

mentioned standards. The data is checked for illegal numbers

not conforming to the above standards. The syntax for NR1

data (implicit point representation) is shown in Fig.11.4 .

Fig.11.3 General syntax for character data fields

931103e

Alpha Alpha Prnt.

ASCII Char.

Except

SP , ; DEL

–

Chapter 11– Appendix 2: Interface

Character Data

BB1119 – 11 11–11

2238 Mediator

User Manual

NR2 data (floating point number with an explicit decimal

point) is not represented below as it is included in NR3.

Mediator usually accepts the full NR3 (explicit point scaled

representation, see Fig.11.5 ), except where syntax diagrams

state that NR1 or NR2 is required.

A digit is any of the 10 number symbols, 0 through 9.

In this manual both commands and queries are illustrated

using syntax diagrams, and are usually accompanied by ex-

amples. When a syntax diagram illustrates the input of nu-

meric data, an explanation is given as to how the Mediator

accepts the numeric data. A legal range is always given (un-

less only specific values are allowed, and these are shown),

Fig.11.4 Syntax for numerical data of type NR1

Fig.11.5 Syntax for numerical data of type NR3

931104e

–

Digit

931106e

–

Digit

Suffix

(input only)

E-Digit

NR1 (1-3)

Digit

Chapter 11 – Appendix 2: Interface

Character Data

11–12 Brüel & Kjær2238 Mediator

User Manual

and the value received by the amplifier is rounded so that it

lies within the allowable range.

If many values are legal, the explanation given will indicate

whether Mediator chooses the nearest value above (Round

Up) the nearest value below (Round Down) or just the nearest

value (Round Nearest). The value is always rounded to the

given resolution.

The default value for the parameter is also given. This is the

factory setting for that parameter.

11.4.2 String Data

String data is the format used to enter text in a message. In

addition, it is used to enter special characters not allowed in

character data fields.

String data is always enclosed in quotation marks. To include

one quotation mark in the string data field, two quotation

marks need to be entered. Fig. 11.6 gives the syntax for en-

tering string data. The length in characters of a fixed length

string data is given in parentheses after the data type name.

Example:

"This is the text."

"This text contains "" one quotation mark."

Fig.11.6 Syntax for entering string data

931107e

(to be

inserted)

Any ASCII

character

except"

Chapter 11– Appendix 2: Interface

Information Protocol

BB1119 – 11 11–13

2238 Mediator

User Manual

11.5 Information Protocol

11.5.1 Introduction

Each command or query described in this manual has a name,

or Header. The header can be thought of as a variable name,

and the value or option it is assigned is the parameter value

which the Mediator actually uses to carry out the specified

operation. See Fig.11.7.

11.5.2 Header

The Header command allows you to specify how the response

messages are to be sent from the Mediator:

OFfIf you specify OFf, no header will be re-

turned to you by the amplifier as a query

response.

Fig.11.7 The header designates the parameter name for the value (or

option) which follows

Fig.11.8 Syntax for Header command

941101e

Par. Header Parameter

Value(s)

Char

–

970184e

HEADER SHORT

To Mediator

OFF

LONG

–

Chapter 11 – Appendix 2: Interface

Information Protocol

11–14 Brüel & Kjær2238 Mediator

User Manual

Short If you specify Short as the header, charac-

ter data from the amplifier will be sent as

mnemonics. That is, the letters shown in

bold only for each command.

Long If you specify a Long header, the Mediator

will return the entire name for each com-

mand header and character data.

Example of a response with a Long header to the query:

Bandwidth?

:BANDWIDTH OCTAVE_3

Example of the response with a Short header to query:

Bandwidth?

:B O_3

Example of the response with an OFf header to the query:

Bandwidth?

O_3

You can query Mediator regarding the header setting as

shown in Fig. 11.9.

The default setting is Long

Fig.11.9 Syntax for Header? query and Mediator response

970185e

TeHEADER?

Header OFf

From Mediator

Header

Char

HEADER

To Mediator

–

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–15

2238 Mediator

User Manual

Example Response:

:Header Long

:H S

11.6 Setting up the PC

Warning! When connecting Mediator to a PC, ensure that

both the computer and the Mediator are switched off. Other-

wise the instruments could be damaged.

1. Connect the computer to Mediator via the SerialInter-

face socket on the base of the Mediator using 9-pole

Cable with 25-pole Adaptor AO 1386. If the computer has

a 9-pole interface socket, remove the adaptor.

2. Start a communications program (e.g. BK–Link or Pro-

Comm) on the computer.

Refer to section 7.2 for Brüel & Kjær software such as

Noise Explorer 7815, Protector 7825 and Evaluator

7820/7821, which are written specifically for communi-

cating with your sound level meter, working with and

displaying sound level meter data.

3. Configure the computer as follows (depending on the com-

munications program):

9600 Baud

8 data bits

1 stop bit

Parity: none

Handshake: Hardwired

4. Switch on Mediator via the interface.

5. Set the Mediator’s Baud Rate to 9600 and Handshake

to Hardwired (see section 3.1.5). for the remote inter-

face.

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–16 Brüel & Kjær2238 Mediator

User Manual

6. Press 〈Enter〉 on the computer.

Communication is established and the prompt (> ) is

shown on the computer screen. The Mediator can now be

controlled from the computer.

Note: The baud rates and handshake of the Mediator and

the computer must be the same to enable them to communi-

cate without losing or corrupting data. A higher baud rate

may be possible depending on your system.

11.6.1 Commands

The command and query messages available are listed in

Table 11.1. The commands and queries are explained in the

following sections, in alphabetical order.

Message Command Query Message Command Query

Bandwidth ••PArameter •

Continue •PAUse •

Error •RAnge ••

File •REset •

Frequency_

Weighting_1 ••SEtup ••

Frequency_

Weighting_2 ••STatus •

Header ••SYstem ••

IDentify •Version •

Key •

Table 11.1 Command and query message overview

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–17

2238 Mediator

User Manual

11.6.2 Bandwidth

The Bandwidth command is used for setting the bandwidth

for Detector 1. The syntax is shown in Fig. 11.10.

The default setting is: Broad band

Note: The 1/3- and 1/1-octave options are only available when

the 1/1-octave and 1/3-octave Filter Set is installed in the

Mediator.

The syntax for the query Bandwidth? and the response re-

turned by the Mediator appears in Fig. 11.11.

Example (setting the bandwidth to 1/3 octave):

Interface job from controller:

Bandwidth Octave_3

Fig.11.10 Syntax for Bandwidth command

Fig.11.11 Syntax for the Bandwidth? query and Mediator response

980293e

To Mediator

: BANDWIDTH

BROAD

OCTAVE_1

OCTAVE_3

–

980147e

From Mediator

:Bandwidth

Char

BANDWIDTH?

To Mediator

BANDWIDTH?SP

–

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–18 Brüel & Kjær2238 Mediator

User Manual

Query from controller:

Bandwidth?

From Mediator:

:Bandwidth Octave_3

11.6.3 Continue

The Continue command starts a measurement without reset-

ting the mediator. The syntax is shown in Fig. 11.12.

11.6.4 Error?

The Error? query returns information from the Mediator

about the error condition of the device, where “Error No” is

the number of the error, “Err Msg” is a string containing a

short description of the error, and “Log Buffer” contains a

Fig.11.12 Syntax for Continue command

Fig.11.13 Syntax for Error? query and amplifier response

980157e

CONTINUE

To Mediator

From Mediator

ERROR?

Header OFf

970204e

Error No

Nr.1

Err Msg

String (25)

Log Buffer

String (100) Te

ERROR?SP

–,

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–19

2238 Mediator

User Manual

string with the interface message which was executing when

the error occurred. If the error was a device error, the log

buffer will be empty.

After the response to the ERror? query is sent, the error

buffer is reset and Error No is set to 0. See section 10.4 for

a detailed listing of all interface and device errors.

Example:

Query from controller:

Error?

From Mediator:

:Error 16,"UNEXPECTED END DETECTED ","^10^END

11.6.5 File

The File queries are used for performing operations on the

files in the Mediator memory.

Files are numbered from 0 to 512 for each software package.

File number 0 is only used for back-up purposes, so that the

total number of files is 511. File names normally consist of

three characters with a three character extension, however,

the file name may contain up to 8 characters.

Copy? query

Copy? is used for getting one or more files from the Mediator

File Manager. You can specify a block of files by using the

“*” and “?” wild card characters. The syntax for the Copy?

query is shown in Fig. 11.14.

The first figure in the block size descriptor specifies how many

figures follow, these figures specify the size of the binary data

block.

Example (copying file 21 from the Basic software package):

Interface job from controller:

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–20 Brüel & Kjær2238 Mediator

User Manual

File:Copy? "021.M26"

From Mediator:

:FILE:COPY "021.M26",#3409 (binary data)

Delete? query

DElete? is used for deleting one or more files from the Me-

diator File Manager. You can specify a block of files by using

the “*” and “?” wild card characters. The syntax for the DE-

lete? query is shown in Fig.11.15.

The response to a DElete? query is a File_Ok or File_Failed

message from the Mediator.

Example (deleting all files from the Basic software module):

Interface job from controller:

File:DElete? "*.M26"

From Mediator:

Fig.11.14 Syntax for the File:Copy command

980303e

To Mediator

FFILE CCOPY?

From Mediator

, ,

File Check

Sum

(0...65535)

Nr 1

–

String (12)

File Name

String (12)

File Name Block File

Data

(Block Size

Descriptor)

Binary Data

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–21

2238 Mediator

User Manual

:FILE:DELETE FILE_OK

Directory? Query

The File_DIrectory? query shows the entire contents of the

Mediator File Manager or you can specify the file names

you want to see. The directory string shows the number of

files, the file names and the associated file information, i.e.,

day, month, year, hour, minute and second. The syntax for

the File_DIrectory? query and response returned by the Me-

diator appear in Fig. 11.16.

Fig.11.15 Syntax for the File:DElete command

Fig.11.16 Syntax for the File_DIrectory? query and Mediator response

980302e

From Mediator

FILE SP

DELETE?

To Mediator

FILE DELETE?

FILE_OK

FILE_FAIL

File Name

String (12)

–

980211e

From Mediator

FILE

File Size

String

DIRECTORY?

File Name

String (12)

To Mediator

: :

FILE DIRECTORY?

Number of

Files

Nr 1

File Name

String (12) Te

, , Te

File Info

String

–

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–22 Brüel & Kjær2238 Mediator

User Manual

Example (show all files with extension M26):

Interface job from controller:

File:DIrectory? "*.M26"

From Mediator:

:FILE:DIRECTORY 7,"MEASPAR.M26","1998-07-23

09:57:30","468","SETUP_0.M26","1998-07-23

09:30:58","115","SETUP_1.M26","1998-07-23

09:30:58","115","SETUP_2.M26","1998-07-23

09:30:58","115","SETUP_3.M26","1998-07-23

09:30:58","115","SETUP_4.M26","1998-07-23

09:30:58","115","001.M26","1998-07-23 10:13:46","409"

Space? Query

The File_Space? query shows how much memory space re-

mains in the Mediator memory. The syntax for the

File_Space? query and response returned by the Mediator

appear in Fig. 11.17.

Example (space query):

Interface job from controller:

File:Space?

From Mediator:

Fig.11.17 Syntax for the File_Space? query and Mediator response

980301e

From Mediator

To Mediator

FILE

SPACE?

Disk space

in Bytes

String

–

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–23

2238 Mediator

User Manual

:FILE:SPACE? "2011648"

Save? query

SAve? is used for storing the current measurement file (refer

to section 6.1.1 for information about saved data). The file is

saved with a file number and an extension that identifies the

current software module, for example, 005.M26. The syntax

for the SAve? query is shown in Fig. 11.18.

The response to a SAve? query is a File_Ok or File_Failed

message from Mediator. The File_Failed message will nor-

mally only occur if there is not sufficient memory space.

Example (saving the current measurement file):

Interface job from controller:

File:SAve?

From Mediator:

:FILE:SAVE FILE_OK

11.6.6 Frequency_Weighting_1

The Frequency_Weighting_1 command is used for setting up

the frequency weighting options for Detector1. The syntax is

shown in Fig.11.19.

Fig.11.18 Syntax for the File:SAve command

980380e

From Mediator

FILE SP

–

To Mediator

FILE SAVE?

SAVE?

FILE_OK

FILE_FAIL

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–24 Brüel & Kjær2238 Mediator

User Manual

The default setting is: A-weighting

The frequency weighting values are: A, C, Lin, F20, F25,

F31_5, F40, F50, F63, F80, F100, F125, F160, F200, F250,

F315, F400, F500, F630, F800, F1K, F1K25, F1K6, F2K,

F2K5, F3K15, F4K, F5K, F6K3, F8K, F10K, F12K5.

Note 1: The “K” is used as decimal separator.

Note 2: Some combinations of weightings are mutually ex-

clusive for the two detectors.

The syntax for the query Frequency_Weighting_1? and the

response returned by the Mediator appears in Fig. 11.20.

Example (setting frequency weighting for Detector1 to C-

weighting):

Interface job from controller:

Fig.11.19 Syntax for Frequency_Weighting_1 command

Fig.11.20 Syntax for the Frequency_Weighting_1? query and Mediator re-

sponse

Parameter

Char/Nr.

To Mediator

980163e

FREQUENCY_WEIGHTING_1SP

–

980149e

From Mediator

To Mediator

Wgt. Value

Char

FREQUENCY_WEIGHTING_1?

–

FREQUENCY_WEIGHTING_1?

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–25

2238 Mediator

User Manual

Frequency_Weighting_1 C

Query from controller:

Frequency_Weighting_1?

From Mediator:

:FREQUENCY_WEIGHTING_1 C

11.6.7 Frequency_Weighting_2

The Frequency_Weighting_2 command is used for setting up

the frequency weighting options for Detector2. The syntax is

shown in Fig.11.21.

The default setting is: Peak and C-weighting

Peak weighting can be C or L.

The syntax for the query Frequency_Weighting_2? and the

response returned by the Mediator appears in Fig. 11.22.

Example (setting frequency weighting for Detector2 to Peak

and L-weighting):

Interface job from controller:

Frequency_Weighting_2 Peak_L

Query from controller:

Frequency_Weighting_2?

From Mediator:

Fig.11.21 Syntax for Freq_Wgt_2 command

980345e

From Mediator

FREQUENCY_WEIGHTING_2?

PEAK_C

PEAK_L

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–26 Brüel & Kjær2238 Mediator

User Manual

:FREQUENCY_WEIGHTING_2 PEAK_L

11.6.8 Header

Refer to section 11.5.2.

11.6.9 Identify?

The Identify? query returns the device ID, which for the

Mediator is “B&K 2238”. This is a standard Brüel & Kjær

method of determining which device is currently connected

via the interface. The syntax for the Identify? query is shown

in Fig.11.23.

Fig.11.22 Syntax for the Frequency_Weighting_2? query and Mediator re-

sponse

Fig.11.23 Syntax for the Identify? query and Mediator response

980150e

From Mediator

To Mediator

Wgt. Value

Char

FREQUENCY_WEIGHTING_2?

–

FREQUENCY_WEIGHTING_2?

970199e

IDENTIFY?

To Mediator

Header OFf

From Mediator

:Device ID

String (8)

IDENTIFY SP

–

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–27

2238 Mediator

User Manual

Example:

Query from controller:

Identify?

From Mediator:

:IDENTIFY "BK2238"

11.6.10 Key

The Key command allows you to use the pushkey functions

via the interface. See section 2.3 for a description of pushkey

functionality. The 16 keys on the front panel are numbered

according to Fig. 11.24.

Fig.11.24 Numbering of keys on the front panel

910

14 15

980205e

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–28 Brüel & Kjær2238 Mediator

User Manual

You may use the key numbers shown in Fig. 11.24 or the key

names used in the syntax diagram in Fig. 11.25.

Note: An interface error may occur if a key command se-

quence is used for recalling one of the four user defined set-

ups or the factory set-up or if you try to change the interface

parameters in the Remote Interface Window. This is be-

cause these commands reset the interface to set up the new

interface parameters.

Fig.11.25 Syntax for the Key command

ONOFF

SYSTEM

DATA

RANGE

SETUP

DOWN

LEFT

RIGHT

RESET_START

PAUSE_CONTINUE

MEASURE

SOFT_LEFT

SOFT_RIGHT

LIGHT

980159e

KEY

To Mediator

–

CALIBRATE

Value

(Key 1 to16)

Nr. 1

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–29

2238 Mediator

User Manual

Example (key sequence for stepping the measurement range

10 dB up):

Interface job from controller:

Key 5<Te>

Key 10<Te>

Key 14<Te>

Alternatively:

Key RAnge<Te>

Key Soft_Left<Te>

Note: When you use a “manual” key sequence command you

must normally ensure that the cursor is in a known position,

for example by sending the Key MEasure<Te> and Key

Soft_Right<Te> commands immediate before the key se-

quence.

11.6.11 PArameter?

The PArameter? query is used for checking the selected meas-

urement parameters. The syntax for the query PArameter?

and the response returned by the Mediator appears in

Fig. 11.26.

Fig.11.26 Syntax for the PArameter? query and Mediator response

980346e

PARAMETER

Sub Header?

See table See table

See text

See table

Frequency

Weighting

Parameter

Time

Weighting

Parameter

: :

To Mediator

–

From Mediator

Parameter

–Char

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–30 Brüel & Kjær2238 Mediator

User Manual

Sub Header Frequency

Weighting

Setting

Time

Weighting

Setting

Aux_1——

Aux_2——

Dose — —

Dose_Lav — Fast

Slow

EAd——

ED ——

ELapsed — —

Inst

Lin

Octave

Fast

Slow

Impulse

LAv

Lin

Octave

Fast

Slow

LEq

Lin

Octave

—

LEPd——

LIeq

Lin

Octave

—

Table 11.2 Sub-header and parameter settings for

the PArameter? query

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–31

2238 Mediator

User Manual

LMAx

Lin

Octave

Fast

Slow

Impulse

LMIn

Lin

Octave

Fast

Slow

Impulse

Lin

Octave

Fast

Slow

Impulse

LPK ——

LPKMax — —

No_Peaks — —

Overload — —

Underrange — —

Sub Header Frequency

Weighting

Setting

Time

Weighting

Setting

Table 11.2 Cont.Sub-header and parameter settings for

the PArameter? query

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–32 Brüel & Kjær2238 Mediator

User Manual

Example (reading the measured LAeq value):

Query from controller:

PArameter:LEq? A

From Mediator (value in dB):

:PARAMETER_LEQ 46.9

11.6.12 PAUse

The PAUse command message puts the Mediator in Pause

mode. The pause will take effect on the next even second of

the Mediator’s clock. Therefore, you must wait for one full

second before sending the next command to be sure that the

pause condition is in effect.

11.6.13 RAnge

The RAnge command message is used for setting the meas-

urement range.

Fig.11.27 Syntax for the PAUse command

Fig.11.28 Syntax for the RAnge command

980156e

PAUSE

To Mediator

980308e

Value

(80-140)

Nr 1

RANGE?

To Mediator

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–33

2238 Mediator

User Manual

The default range setting is: 30 – 110 dB

You must enter the Value field as the upper value in the

desired measurement range. Table 11.3 lists the default field

settings.

The RAnge? query message shows the current measurement

range. The syntax for the query and the response returned

by the Mediator appears in Fig. 11.29.

Field Name Field Setting Comments

Value (command) 80

100

110

120

130

140

0 – 80

10 – 90

20 – 100

30 – 110

40 – 120

50 – 130

60 – 140

Status (query response) 0 – 80

10 – 90

20 – 100

30 – 110

40 – 120

50 – 130

60 – 140

These are the default ranges.

However, if a non-standard

transducer is used the ranges

may be different.

Table 11.3 RAnge data fields and codes

Fig.11.29 Syntax for the RAnge? query message and Mediator response

980152e

From Mediator

TeRANGE?

RANGE?

To Mediator

–

Value

(80 - 140)

Nr 1

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–34 Brüel & Kjær2238 Mediator

User Manual

Example (setting the measurement range to 50 – 130 dB):

Interface job from controller:

RAnge 130

Query from controller:

RAnge?

From Mediator:

:RANGE 130

11.6.14 REset

The REset command message resets the Mediator. The meas-

urement is restarted, i.e., the current measurement data is delet-

ed and the buffer and the Elapsed Time parameter are set

to zero. This command is equivalent to pressing the key.

Note: There is no reset warning.

11.6.15 SEtup

The SEtup commands are used for setting up most of the

measurement parameters in the Measurement Setting menu.

A separate sub-header is used for the Auto Start commands,

to distinguish the four possible Auto Start sequences.

Auto Start Command

The syntax for the Auto_Start_X command is shown in

Fig. 11.31.

Fig.11.30 Syntax for the REset command

980155e

TeRESET:

To Mediator

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–35

2238 Mediator

User Manual

Example (setting the owner for Auto Start number 3 to the

current application module):

Interface job from controller:

SEtup:Auto_Start_3:Application Current_Bz

Query from controller:

SEtup:Auto_Start_3?

From Mediator:

:SETUP:AUTO_START_3

1998,7,23,11,13,27,"BZ7126",1

Fig.11.31 Syntax for the SEtup:Auto_Start_X command

Sub Header 1 Sub Header 2 Parameter Setting

Auto_Start_1

Auto_Start_2

Auto_Start_3

Auto_Start_4

Application Current_Bz

None Char.

Setup_No1 ... 4 NR1

Time

(Year) –3000 ... 3000

(Month) 1 ... 12

(Day) 1 ... 31

(Hour) 0 ... 23

(Minute) 0 ... 59

(Second) 0 ... 59

NR1

Table 11.4 Auto_Start_X sub-header and parameter settings

980305e

SETUP Sub Header 1

See table See table

Parameter

: : Sub Header 2

See table

To Mediator

–

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–36 Brüel & Kjær2238 Mediator

User Manual

Other SEtup Commands

The remaining SEtup commands use the syntax illustrated

in Fig. 11.32.

Fig.11.32 Syntax for the SEtup command

Sub Header Parameter Setting Comments

Aux_1_FW LINear_Frequency_

Weighting

Detector_1_Frequen

cy_Weighting

Char Sets Linear Frequency

weighting or Detector 1 out-

put to the Aux 1 output

Criterion_Level 70 ... 100 NR3 Sets Criterion level between

70 and 100 dB

Exchange_Rate 4, 5NR1 Sets Exchange Rate to 4 or

5dB

Exposure_Time (Hour) 0 ... 23

(Minute) 0 ... 59 NR1 Sets Exposure Time in

hours and minutes

Peaks_Over 0 ... 180 NR3 Sets the peak counting level

PREset_Time (Hour) 0 ... 9999

(Minute) 0 ... 59

(Second) 0 ... 59

NR1 Sets the measurement time

for each measurement in an

Auto Start sequence

Random_Frontal Random

Frontal Char Sets Random or Frontal fre-

quency correction

Recall 0 ... 4 NR1 Recall measurement set-up

0 to 4 (0 is default set-up)

Table 11.5 Sub-header and parameter settings for the SEtup command

980215e

: :

SETUP SP

—

Sub Header

See table See table

Parameter

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–37

2238 Mediator

User Manual

The syntax for the query SEtup? and the response returned

by Mediator appears in Fig. 11.33.

SAve 1 ... 4 NR1 Saves measurement set-up

in memory 1 to 4

SEquence OFf, ON Char Switches the Auto Start

sequence On or Off

Threshold_Level 0 ... 100 NR3 Sets the Threshold level in

dB for Occupational Health

Wind_Screen OFf, ON Char Switches the windscreen

frequency correction On or

Off

Sub Header Parameter Setting Comments

Table 11.5 Sub-header and parameter settings for the SEtup command

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–38 Brüel & Kjær2238 Mediator

User Manual

Example (checking the Preset Time set to 10 minutes):

Query from controller:

SEtup:Preset_Time?

From Mediator:

:SETUP:PRESET_TIME 0,10,0

Sub Header

Auto_Start_1?

Auto_Start_2?

Auto_Start_3?

Auto_Start_4?

Aux_1?

Aux_1_FW?

Aux_2?

Criterion_Level?

Exchange_Rate?

Exposure_Time?

Peaks_Over?

Preset_Time?

Random_Frontal?

SEquence?

Threshold_Level?

Wind_Screen?

Table 11.6 SEtup queries

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–39

2238 Mediator

User Manual

11.6.16 STatus?

The STatus? query is used to check whether the Mediator is

in pause mode or is measuring. The syntax is shown in

Fig. 11.34.

The status can be: Measuring or Paused

Example:

Query from controller:

STatus?

Fig.11.33 Syntax for the SEtup? query and Mediator response

Fig.11.34 Syntax for the STatus? query and Mediator response

980216e

To Mediator

: :

SETUP

From Mediator

Sub Header?

See table

SETUP Sub Header?

See table

Parameter

See table

–

980153e

From Mediator

TeSTATUS?

STATUS?

To Mediator

–

Status

(Measuring/

Paused) Char

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–40 Brüel & Kjær2238 Mediator

User Manual

From Mediator:

:STATUS PAUSED

11.6.17 SYstem

The SYstem command is used for setting the date and time

on the Mediator’s calendar and clock. The syntax is shown

in Fig. 11.35.

The syntax for the query SYstem? and the response returned

by the Mediator appears in Fig. 11.36.

Example (setting the time to 1. January 1999, 10:15:00):

Interface job from controller:

SYstem:Time 1999,01,01,10,15,00

Query from controller:

SYstem:Time?

Fig.11.35 Syntax for SYstem commands

Sub Header Date and Time Setting Comments

Time

(Year) –3000 ... 3000

(Month) 1 ... 12

(Day) 1 ... 31

(Hour) 0 ... 23

(Minute) 0 ... 59

(Second) 0 ... 59

NR1 Comma separated in the

form of:

YY,MM,DD,HH,MM,SS

Table 11.7 Parameter settings for the SYstem:Time command

980217e

SYSTEM TIME

Date (YY,MM,DD)

Time (HH,MM,SS)

Nr 1

Chapter 11– Appendix 2: Interface

Setting up the PC

BB1119 – 11 11–41

2238 Mediator

User Manual

From Mediator:

:SYSTEM:TIME 1999,01,01,10,15,00

11.6.18 Version

The Version? query message shows the running software ver-

sion of the Mediator. The Syntax is shown i Fig. 11.37.

Fig.11.36 Syntax for the SYstem? queries and Mediator response

Fig.11.37 Syntax for the Version? query message and Mediator response

TIME?

SYSTEM

::Parameter

Value

Nr 1

TIME?

980219e

SYSTEM

To Mediator

From Mediator

980304e

To Mediator

VERSION?

From Mediator

Module

(BZ....) Version No.

, ,

String Nr 1

Revision No. History No.

Nr 1 Nr 1

:SP

–

Chapter 11 – Appendix 2: Interface

Setting up the PC

11–42 Brüel & Kjær2238 Mediator

User Manual

Example (checking the current version):

Query from controller:

Version?

From Mediator:

:VERSION "BZ7126",1,0,0

Field Name Field Setting Comments

Version status BZ 7126

BZ 7125

BZ 7123

BZ 7124

Basic SLM Software

Enhanced SLM Software

Frequency Analysis Software

Logging SLM Software

Table 11.8 Version data fields and codes

BB1119 – 11 12 –43

2238 Mediator

User Manual

Chapter 12

Index

Numerics

1/1-octave and 1/3-octave filter set ............... 1–5

9-pole cable .............................. 1–4, 7–5, 11–15

About System Window .................................. 3–8

AC Output ..................................................... 7–6

Accessories (effect of) .................................... 9–5

Application

module ............................................ 1–7, 3–4

programs ................................ 1–5, 2–8, 7–5

status ..................................................... 4–10

Window .................................................... 3–4

ASCII characters ....................................... 11–10

Auto Start .................................. 4–9, 5–10, 6–2

application status .................................. 4–10

sequence ................................................ 4–10

Window .................................................... 4–9

Auto_Start_1...4 command ....................... 11–35

Auto_Start_1..4? query ............................. 11–38

Aux 1 ............................................ 1–5, 4–8, 9–4

Aux 2 ............................................ 1–5, 4–8, 9–4

Aux_1? query ............................................. 11–38

Aux_1_FW command ................................ 11–36

Aux_1_FW? query ..................................... 11–38

Aux_2? query ............................................. 11–38

A-weighting ................................................... 1–5

Backlight .......................................... 1–14, 2–10

pushkey .................................................. 2–10

Back-up battery ................................. 1–13, 2–4

Bandwidth ................................................... 5–10

command ............................................. 11–17

Bar graph ................................ 2–10, 4–4, 5–11

Basic

configuration ........................................... 1–4

SLM software ................................. 1–4, 1–7

version (BZ 7126) .................................... 1–3

Batteries ............................. 6–2, 8–3, 9–4, 9–5

checking level .......................................... 2–2

fitting ....................................................... 2–2

handling ................................................... 2–3

operating time ......................................... 2–3

recharging ................................................ 2–3

saving ..................................................... 2–10

type .......................................................... 1–4

Battery

back-up ......................................... 1–13, 2–4

flat ............................................................ 2–4

level ........................................................ 2–12

remaining time ........................................ 2–3

symbol ...................................................... 2–2

Baud rate ........................ 3–5, 7–3, 7–4, 11–15

Broadband data ......................... 1–14, 6–3, 6–4

Buffer ..................................... 1–13, 6–2, 11–34

Calendar data .............................................. 1–12

Calibrate pushkey ......................................... 2–8

Calibration .................................................... 5–2

data ........................................................ 1–12

Index

12 –44 Brüel & Kjær2238 Mediator

User Manual

factor .......................................................1–13

Free-field/Diffuse Field ...........................5–2

history ....................................................1–12

menu ............................................1–10, 1–12

principle of ...............................................5–2

set-up .............................................1–13, 6–3

signal ........................................................5–2

time ...........................................................6–3

when to .....................................................5–2

Window .....................................................5–2

Calibrator

types .........................................................5–3

Cancel pushkey ............................................2–10

Care of Mediator ............................................8–2

Centre frequency .........................................5–10

Changing

applications ..............................................1–7

displayed parameter ..............................5–11

language .................................................2–12

Character data ................................11–9, 11–10

Checking

battery level .............................................2–2

calibration ................................................5–7

Cleaning Mediator .........................................8–2

COM port .......................................................7–5

Command

Auto_Start_1...4 ...................................11–35

Aux_1_FW ............................................11–36

Bandwidth ............................................11–17

Continue ...............................................11–18

Criterion_Level ....................................11–36

Exchange_Rate ....................................11–36

Exposure_Time ....................................11–36

File ........................................................11–19

Frequency_Weighting_1 ......................11–23

Frequency_Weighting_2 ......................11–25

Key ........................................................11–27

PAUse ...................................................11–32

Peaks_Over ..........................................11–36

Preset_Time .........................................11–36

Random_Frontal ..................................11–36

RAnge ...................................................11–32

Recall ....................................................11–36

REset ....................................................11–34

SAve .....................................................11–37

SEquence ..............................................11–37

SEtup ....................................................11–34

SYstem .................................................11–40

Threshold_Level ..................................11–37

Wind_Screen ........................................11–37

Command message overview ....................11–16

Communication

error ..........................................................7–5

program ................................................11–15

Compound message .....................................11–4

Computer (setting up) ...............................11–15

Concatenator ................................................11–8

Condenser microphone ................1–4, 5–3, 9–2

Connecting a microphone extension cable ...2–7

Connectors .....................................................1–5

Constructing interface message .................11–7

Continue command ....................................11–18

Contrast .........................................................3–7

Controlling Mediator via the interface .......11–3

Conventions in this Manual ..........................1–3

Correction filters .........................1–5, 4–7, 5–2

Creterion_Level command ........................11–36

Criterion level ..............................................4–12

Criterion_Level? query ..............................11–38

Cursor keys ..................................2–9, 3–2, 4–2

C-weighting ....................................................1–5

D/A converter .................................................1–5

DAT recorder .................................................4–8

Data

files ...................................1–10, 1–12, 1–13

extension ..........................................1–13

menu ..........................................2–8, 6–4

number of .........................................1–13

set-up data .......................................1–13

system .................................................6–2

Files pushkey .........................2–8, 6–7, 7–3

separator ................................................11–8

types .......................................................11–9

character ........................................11–10

numeric ...........................................11–10

string ..............................................11–12

Date and time

information ..............................................6–2

setting .......................................................3–4

DC Output ............................................4–9, 7–6

Decimal separator .....................................11–24

Default

measurement set-up ..............................4–13

parameters ....................................2–5, 10–4

set-up ........................................................2–5

Delete

all files ......................................................6–9

files ...........................................................6–9

Detectors .1–5, 2–10, 4–5, 9–3, 11–23, 11–25

Peak ..........................................................1–5

RMS ..........................................................1–5

setting up

bandwidth ..........................................4–5

frequency weighting ..........................4–5

Diffuse sound field .........................................4–7

Disk Summary ...............................................6–9

Display ..................................................3–7, 9–4

Displayed parameters .................................5–11

Dose

levels .......................................................4–11

percentage ................................................1–9

Dose%X ..........................................................1–9

Dose%XY4 ......................................................1–9

Index

BB1119 – 11 12 –45

2238 Mediator

User Manual

Dose%XY5 ..................................................... 1–9

Dynamic range .............................................. 4–3

EA .................................................................. 1–8

Effect of accessories ...................................... 9–5

Elapsed time ......................................... 1–9, 6–3

EMC ...................................................... 9–5, 9–6

Enhanced SLM Software ..................... 1–6, 3–4

Environmental effects ................................... 9–4

Error

list of interface ...................................... 10–8

messages .............................................. 10–11

Error? query .............................................. 11–18

Evaluator .......................................... 7–4, 11–15

Exchange rate .............. 4–4, 4–11, 5–11, 10–2

Exchange_Rate command ........................ 11–36

Exchange_Rate? query ............................. 11–38

Explicit point scaled representation ........ 11–11

Exposure time .................................. 4–11, 10–2

Exposure_Time command ........................ 11–36

Exposure_Time? query ............................. 11–38

External

DC supply ................................................ 9–4

power socket ............................................ 2–4

power supply ........................................... 2–4

Fast (F) .......................................................... 1–5

Field

parameter .............................................. 2–12

value ...................................................... 2–12

File

delete ........................................................ 6–9

extension .................................................. 6– 2

list ................................................... 6–7, 6–8

Manager ................................. 2–8, 6–4, 6–7

Options Window ................................ 6–8

names ....................................................... 6–2

print ................................................ 6–6, 6–8

recall ........................................................ 6–8

size ........................................................... 6–7

store ......................................................... 6–5

File command ............................................ 11–19

File_Copy query ........................................ 11– 19

File_DElete query ..................................... 11–20

File_DIrectory? query ............................... 11–21

File_SAve query ........................................ 11–23

File_Space? query ..................................... 11–22

Filter set ......................... 1–4, 1–7, 4–5, 11–17

Fitting batteries ............................................ 2–2

Flash RAM ......................................... 1–13, 2–4

Formats for interface messages ................. 11–4

Frequency

Analysis Software ................. 1–4, 1–5, 3–4

response ................................................... 9–3

weighting ..1–5, 1–7, 4–5, 4–8, 5–11, 7–6,

9–3

Frequency_Weighting_1 command .......... 11–23

Frequency_Weighting_1? query ............... 11–24

Frequency_Weighting_2 command .......... 11–25

Frequency_Weighting_2? query ............... 11–25

Frontal setting .............................................. 5–3

General

measurement parameters ....................... 4–3

specifications ........................................... 9–2

Window ......................................... 4–3, 4–11

Getting started .............................................. 2–2

Handshake ..................... 3–6, 7–3, 7–4, 11–15

Hardwired ........................................ 3–6, 11–15

Header

long ...................................................... 11–14

path ........................................................ 11–4

separator ................................................ 11–8

short ..................................................... 11–14

How Mediator works ..................................... 1–4

Hydrophone ................................................... 5–3

Identify? query .......................................... 11–26

Illegal entry ...................................... 1–11, 2–12

Implicit point representation ................... 11–10

Impulse (I) ..................................................... 1–5

Indicator range .............................................. 9–2

Inherent noise ...................................... 9–2, 9–5

Initial

calibration parameters ......................... 1–13

Input/Output

function .................................................... 4–8

Window .................................................... 4–8

Instantaneous value ................................... 5–11

Interface

error .......................................... 10–8, 11–28

message formats .................................... 11–4

parameters (setting up) ................. 3–5, 7–3

International standards ............................... 3–8

Joining messages ........................................ 11–5

Key

command ............................................. 11–27

position ................................................ 11–27

Index

12 –46 Brüel & Kjær2238 Mediator

User Manual

Language

changing ........................................2–12, 9–4

setting up .................................................3–7

Latched overload .........................................2–11

LAV ...................................................4–11, 10–2

LAV5 ............................................................10–2

LCD screen ....................................................3–7

LDOD .............................................................4–5

Left/Right Arrow pushkey ............................2–9

Light (backlight) ..........................................1–14

Linear weighting ...........................................1–5

Logging SLM Software .........................1–5, 3–4

Long header ...............................................11–14

LOSHA ................................................4–5, 10–2

LXAV ..............................................................4–5

LXE ................................................................1–8

LXep,d ............................................................1–8

LXeq ...............................................................1–8

LXpk ...............................................................1–9

LXpkMax .......................................................6–4

LXpkmax ........................................................1–9

LXYav4 ...........................................................1–8

LXYav5 ...........................................................1–8

LXYinst ..........................................................1–8

LXYmax .........................................................1–8

LXYmin ..........................................................1–8

LXYp ..............................................................1–8

Maintenance and repair ................................8–2

Measurement

Control Window .......................................4–6

data ................................................1–13, 6–3

parameters ..................................1–7, 11–34

range ........ 1–12, 2–9, 2–11, 4–3, 9–2, 9–5

Result pushkey .........1–11, 2–9, 2–13, 3–3

settings ............................................3–2, 4–2

set-up ..................................1–13, 4–12, 6–3

set-up (default) .......................................4–13

Set-up menu ..............1–10, 1–11, 2–9, 4–2

Window ...1–7, 1–10, 2–2, 2–5, 2–9, 2–10,

3–3, .............................................4–4, 5–11

Memory ....................................1–12, 1–13, 9–4

items (selecting) .......................................2–9

keys .........................................................1–10

structure .................................................1–10

Message

compound ...............................................11–4

from the Mediator ..................................11–6

header .....................................................11–4

joining .....................................................11–5

sub-header ..............................................11–4

syntax .....................................................11–6

terminator ...................................11–4, 11–9

to the Mediator ......................................11–4

Messages and warnings ..............................10–5

Microphone ..................................1–4, 5–3, 9–2

extension cable ................................2–7, 5–2

preamplifier ....................................1–4, 9–2

type ...........................................................6–3

Minimum code (mnemonics) ............11–6, 11–8

Mnemonics .............................11–6, 11–7, 11–8

Modem ............................................................3–6

Navigation ...................................................1–10

Noise Explorer ..................................7–4, 11–15

Non-volatile memory ...................................1–13

NR1, NR2, NR3 .........................................11–10

Null-modem cable ..........................................1–4

Number of

data files ........................................1–13, 6–2

peaks ...............................................1–9, 6–4

Numbering files .............................................6–2

Numeric data ..................................11–9, 11–10

Occupational Health

parameters .............................................4–11

Window ...................................................4–11

Octave filters .................................................1–5

Operating time ..............................................2–3

OSHA ...........................................................10–2

Output

AC .............................................................7–6

DC .............................................................7–6

Overall results ...............................................6–3

Overload ............................2–11, 4–4, 6–4, 9–3

warning ....................................................4–4

Overload% ......................................................1–9

Parameter ......................................................1–7

changing the displayed ..........................5–11

default ....................................................10–4

fields .......................................................2–12

header .....................................................11–8

selecting ...................................................2–9

text ............................................................1–3

PArameter? query .....................................11–29

Pause

Continue pushkey ..................................2–10

mode ........ 2–5, 2–8, 2–9, 3–2, 6–4, 11–32

PAUse command .......................................11–32

Peak

detector .....................................................1–5

data .................................1–14, 6–3, 6–4

weighting .....................................4–5, 11–25

Peaks Over

indication .................................................4–4

value .........................................................4–4

Index

BB1119 – 11 12 –47

2238 Mediator

User Manual

Peaks_Over command .............................. 11–36

Peaks_Over? query ................................... 11–38

Power pushkey .............................................. 2–8

Prepolarized microphone ............ 1–4, 5–3, 9–2

Preset Time ................................................... 4–7

Preset_Time command ............................. 11–36

PReset_Time? query ................................. 11–38

a measurement ........................................ 7–3

files .................................................. 6–6, 6–8

Options list .............................................. 6–5

Window .................................................... 6–8

Printer

interface parameters (setting up) ........... 3–6

Interface Window .................................... 3–6

Program message

terminator .................................. 11–5, 11–9

unit separator ........................................ 11–5

Protective cover ............................................. 1–4

Protector ........................................... 7–4, 11–15

Protocol ...................................................... 11–13

Pushkeys

Backlight ............................................... 2–10

Calibrate .................................................. 2–8

Cancel .................................................... 2–10

Data Files ................................................ 2–8

definitions ................................................ 2–8

Left/Right Arrow ..................................... 2–9

Meas. Result ............................................ 2–9

numbering ........................................... 11–27

Pause/Continue ..................................... 2–10

pictograms ...................................... 1–3, 2–8

Power ....................................................... 2–8

Range ....................................................... 2–9

Reset ........................................................ 2–9

Select ...................................................... 2–10

Set-up ....................................................... 2–9

System ..................................................... 2–8

Up/Down Arrow ....................................... 2–9

Quasi-analogue display ..................... 2–10, 4–4

Query ............................................ 11–11, 11–13

Auto_Start_1...4? ................................. 11–38

Aux_1? ................................................. 11–38

Aux_1_FW? .......................................... 11–38

Aux_2? ................................................. 11–38

Criterion_Level? .................................. 11–38

Error? ................................................... 11–18

Exchange_Rate? .................................. 11–38

Exposure_Time? .................................. 11–38

File_Copy ............................................. 11– 19

File_DElete .......................................... 11–20

File_Directory ...................................... 11–21

File_SAve ............................................. 11–23

File_Space? .......................................... 11–22

Frequency_Weighting_1? .................... 11–24

Frequency_Weighting_2? .................... 11–25

Identify ................................................ 11–26

message overview ................................ 11–16

messages .............................................. 11–16

PArameter? .......................................... 11–29

Peaks_Over? ........................................ 11–38

PReset_Time? ...................................... 11–38

Random_Frontal? ................................ 11–38

RAnge? ................................................. 11–33

SEquence? ........................................... 11– 38

SEtup? ................................................. 11–37

STatus? ................................................ 11–39

SYstem? ............................................... 11– 40

Threshold_Level? ................................ 11–38

Version? ............................................... 11–41

Wind_Screen? ...................................... 11–38

Random_Frontal command ...................... 11–36

Random_Frontal? query ........................... 11–38

Range

pushkey ................................ 1–12, 2–9, 4–4

setting .................................................... 2–11

Setting window ........................................ 4–4

RAnge command ....................................... 11–32

RAnge? query ............................................ 11–33

Recall

files ........................................................... 6–8

Files Window ........................................... 6–8

measurement set-up .................. 4–12, 4–13

Setup Window ....................................... 4–13

Recall command ........................................ 11–36

Rechargeable batteries ................................. 2–3

Repair ............................................................ 8–2

REset command ........................................ 11–34

Reset pushkey ............................................... 2–9

Resolution ...................................................... 9–3

RMS

detector ........................................... 1–5, 4–9

weighting ................................................. 4–5

Root header ................................................. 11–4

RS-232 interface ............................................ 1–4

Run/Pause indicator ................................... 2–12

SAve command .......................................... 11–37

Save Setup Window .................................... 4–12

Saved data ..................................................... 6–3

Saving

current meas. set-up ............................. 4–12

measurement set-ups ............................ 4–12

Select pushkey ............................................ 2–10

Selecting

Data Files menu ...................................... 6–4

menu items .............................................. 2–9

parameters ..................................... 2–9, 3–3

Sensitivity value .................................. 5–2, 6–3

Index

12 –48 Brüel & Kjær2238 Mediator

User Manual

SEquence command ..................................11–37

SEquence? query .......................................11–38

Serial

input/output .............................................9–4

interface .................................................11–4

cable ....................................................1–4

parameters .........................................3–5

socket ............................7–2, 7–5, 11–15

Interface Window .....................................3–5

number ..........................................1–13, 6–3

printer ......................................................9–4

Setting up

Auto Start .....................................4–9, 4–11

bandwidth for Detector 1 ........................4–5

Baud Rate ................................................3–5

computer interface ...............................11–15

contrast ....................................................3–7

corrrection filters .....................................4–7

Criterion Level .......................................4–12

date and time ...........................................3–4

Exposure Time .......................................4–11

frequency weighting .......................4–5, 4–8

general measurement parameters ..........4–3

Handshake ...............................................3–6

input/output function ..............................4–8

interface parameters ...............................3–5

Language ..................................................3–7

measurement range .................................2–9

Mediator to start automatically ............5–10

Occupational Health parameters ..........4–11

Preset Time ..............................................4–7

start time for Auto Start .......................4–10

Threshold Level .....................................4–12

windscreen filter ......................................4–8

Settling time ..................................................9–4

Set-up

data ................................................1–14, 6–3

pushkey ....................................................2–9

SEtup command ........................................11–34

SEtup? query .............................................11–37

Short header ..............................................11–14

Shoulder bag .........................................1–4, 8–3

Slow (S) ..........................................................1–5

Socket

External Power ........................................2–4

reference to ...............................................1–3

Soft keys ............................1–3, 1–10, 3–3, 4–2

Software package .......................................11–19

Sound incidence

frontal .......................................................4–7

random .....................................................4–7

SPL ...............................................................5–11

Standards .....................................1–4, 9–2, 9–4

Window .....................................................3–8

Start

date ...........................................................6–3

time ...........................................................6–3

STatus? query ............................................11–39

Store files .......................................................6–5

Storing Mediator ...........................................8–2

String data ......................................11–9, 11–12

Sub-header ...................................................11–4

Summary of contents ....................................1–2

Switching

a sequence On/Off ....................................4–7

Mediator On/Off ..............................2–5, 2–8

Syntax diagrams ...............................11–6, 11–7

System

information ..............................................3–8

key ...................................................3–3, 4–2

menu ................. 1–7, 1–10, 1–11, 2–8, 3–2

pushkey ....................................................2–8

SYstem command ......................................11–40

SYstem? query ...........................................11–40

Tagfiles ...........................................................6–7

parameters ...............................................6–6

Terminator ........................................11–4, 11–9

Threshold level ............................................4–12

Threshold_Level command .......................11–37

Threshold_Level? query ............................11–38

Time .............................................................1–10

weighting ..............................1–5, 1–7, 5–11

Transmission time .......................................11–7

Types of data ................................................11–9

Under-range ........................................2–10, 6–4

Underrange% .................................................1–9

Unknown command .....................................11–8

Up/Down Arrow pushkey ..............................2–9

Value fields ..................................................2–12

Version? query ...........................................11–41

Weight and dimensions .................................9–4

Weightings Window ...........................4–5, 5–10

Wind_Screen command .............................11–37

Wind_Screen? query ..................................11–38

Windscreen ....................................................5–3

filter ..........................................................4–8

Word concatenator .......................................11–8

X suffix ...........................................................1–7

Y suffix ...........................................................1–7

BRUEL & KJAER/BRUEL KJAER 2238 Basic SLM Software

Navigation menu

Versions of this User Manual:

Views

Navigation