Product Data Sheet BRUEL & KJAER/BRUEL KJAER 4231

User Manual: BRUEL & KJAER/BRUEL & KJAER 4231 Product Data

Open the PDF directly: View PDF .
Page Count: 4

Download
Open PDF In Browser	View PDF

Product Data
Sound Level Calibrator — Type 4231
FEATURES:
❍ Conforms to IEC 942 (1988) Class 1 and ANSI
S1.40–1984 (R 1997)
❍ Robust pocket-size design with highly stable level
and frequency
❍ Calibration accuracy ± 0.2 dB
❍ 94 dB SPL, or 114 dB SPL for calibration in noisy
environments
❍ Extremely small influence of static pressure
❍ Sound pressure independent of microphone
equivalent volume

❍ 1 kHz calibration frequency for correct calibration
level independent of weighting networks
❍ Fits Brüel & Kjær 1″ and 1/2 ″ microphones ( 1/4 ″ and
1/ ″ microphones with adaptor)
8
❍ Switches off automatically when removed from the
microphone

USES:
❍ Calibration of sound level meters and other sound
measurement equipment

The Sound Level Calibrator Type
4231 is a handy, portable sound source
for calibration of sound level meters
and other sound measurement equipment. The calibrator is very robust and
stable and conforms to IEC 942 Class
1 and ANSI S1.40-1984.

The Sound Level Calibrator Type
4231 is a pocket-sized, battery operated sound source for quick and direct calibration of sound level meters
and other sound measuring systems.
It fits Brüel & Kjær 1″ and 1/2 ″ microphones and, with adaptors, it can be
used for 1/4 ″ and 1/8 ″ microphones as
well.
The calibration frequency is
1000 Hz (the reference frequency for
the
standardized
international
weighting networks), so the same calibration value is obtained for all
weighting networks (A, B, C, D and
Linear). The calibration pressure of
94 ±0.2 dB re 20 µPa is equal to 1 Pa
or 1 N/m2. The +20 dB level step gives
114 dB SPL which is convenient for
calibration in noisy environments.
The design of the 4231 is based on
a feed-back arrangement to ensure a
highly stable sound pressure level
and ease of use. The feed-back loop
uses a condenser microphone (see
Fig. 1), which is specially developed
for this purpose. This microphone is
optimised to have extremely high sta-

Brüel & Kjær

B
7/6-'89

K

bility and independence of variations
in static pressure and temperature
around the 1 kHz calibration frequency. The result of this is a user-friendly
calibrator where exact fitting of the
microphone is non critical and the effects of changes in temperature and
static pressure are negligible.
The calibrator gives a continuous
sound pressure level when fitted on

a microphone (see Fig. 2) and activated. The sensitivity of the sound measuring equipment can then be
adjusted until it indicates the correct
sound pressure level. The calibrator
is automatically switched off when
removed from the microphone.
A leather protecting case, which
does not need to be removed to use
the calibrator, is supplied.

































,









,,
,


























,,,
,


bp1311141.fm Page 2 Monday, December 6, 1999 10:03 AM

Microphone to be calibrated

1/2" Adaptor

Battery

Lid

Loudspeaker





Reference Microphone

Circuit Board

Pressure Equalization Channels
930129e

Fig.1 Cross-sectional view of Sound Level Calibrator Type 4231. The feed-back loop is
based on a high-quality condenser microphone to ensure a very stable sound pressure level

2

Black process 15,0° 153,0 LPI

Fig.2 Type 4231 fitted to 2238 Mediator.
The calibrator’s centre of gravity is positioned very close to the microphone, giving
a stable set-up

bp1311141.fm Page 3 Monday, December 6, 1999 10:03 AM

Specifications 4231
STANDARDS SATISFIED:
IEC 942 (1988), Sound Calibrators, Class 1
ANSI S1.40–1984 (R 1997), Specifications for
Acoustic Calibrators
NOMINAL SOUND PRESSURE LEVEL:
94.0 dB ±0.2 dB or 114.0 dB ±0.2 dB re 20 µPa
at reference conditions
FREQUENCY: 1 kHz ±0.1%
SPECIFIED MICROPHONE TYPES:
(Conforms to IEC 942 Class 1)
Brüel & Kjær (and similar types) 1″ and 1/2″, 1/4″,
1/8″ with adaptors
EQUIVALENT FREE-FIELD LEVEL:
(0° incidence, re Nominal Sound Pressure Level)
–0.15 dB for 1/2″ Brüel & Kjær Microphones. See
the 4231 User Manual for other microphones
EQUIVALENT RANDOM INCIDENCE LEVEL:
(re Nominal Sound Pressure Level)
+0.0 dB for 1″, 1/2″, 1/4″ and 1/8″ Brüel & Kjær
Microphones.
NOMINAL EFFECTIVE COUPLER VOLUME:
>200 cm3 at reference conditions
TOTAL HARMONIC DISTORTION (THD): <1%
LEVEL STABILITY:
Stabilization Time: 5 s
Short-term: Better than 0.02 dB (as specified in
IEC 942)
1 Year: Better than 0.05 dB
REFERENCE CONDITIONS:
Ambient Temperature: 20°C (68°F)
Ambient Pressure: 1013 hPa
Ambient Humidity: 65% RH
Load: Microphone Type 4134 (effective load volume: 0.25 cm3)

Environmental
AMBIENT CONDITIONS:
Pressure: 650 to 1080 hPa
Humidity: 10 to 90% RH (without condensation)
Effective Load Volume: 0 to 1.5 cm3
INFLUENCE OF AMBIENT CONDITIONS:
Temperature Coefficient: ±0.0015 dB/°C

Pressure Coefficient: +8 × 10–5 dB/hPa
Humidity Coefficient: 0.001 dB/%RH

Power Supply
Batteries: 2 × 1.5 V IEC Type LR6 (“AA” size)
Lifetime: Typically 200 hours continuous operation with alkaline batteries at 20°C (68°F)
Check: When the calibrator can only be operated by keeping the On/Off button continuously
pressed the batteries should be changed.

Dimensions and Weight:
Height: 30 mm (1.2″)
Width: 72 mm (2.8″)
Depth: 72 mm (2.8″)
Weight: 150 g (0.33 lb.), including batteries
Note: All values are typical at 25°C (77°F), unless measurement uncertainty or tolerance field
is specified. All uncertainty values are specified
at 2σ (i.e. expanded uncertainty using a coverage factor of 2)

COMPLIANCE WITH STANDARDS:
CE-mark indicates compliance with: EMC Directive.

Safety

EN 61010–1 and IEC 1010–1: Safety requirements for electrical equipment for
measurement, control and laboratory use.

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

Temperature

IEC 68–2–1 & IEC 68–2–2: Environmental Testing. Cold and Dry Heat.
Operating Temperature: −10 to +50°C (14 to 122°F)
Storage Temperature: –25 to 70°C (–13 to 158°F)

Humidity

IEC 68–2–3: Damp Heat: 90% RH (non-condensing at 40°C (104°F))

Enclosure

IEC 529 (1989): Protection provided by enclosures: IP 50

Ordering Information
Type 4231
Includes the
KE 0317:
2 × QB 0013:
UC 0210:

Sound Level Calibrator
following accessories:
Leather Case
Alkaline Batteries Type LR6
Adaptor for 1/2″ microphones

Optional Accessories
DP 0775:
DP 0774:
DP 0682:

Adaptor for 1/4″ microphones
Adaptor for 1/8″ microphones
Adaptor for Studio Microphones
Types 4003 and 4006

DP 0750:
DP 0887:
DP 0888:

Adaptor for Studio Microphones
Types 4004 and 4007
Adaptor for Head and Torso
Simulator Type 4128
Adaptor for Intensity Probe Sets
Types 3545, 3548, 3583, 3584

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

3

Black process 15,0° 153,0 LPI

Brüel & Kjær

B
7/6-'89

K

HEADQUARTERS: DK-2850 Nærum · Denmark · Telephone: +4545800500 · Fax: +4545801405 · http://www.bk.dk · e-mail: info@bk.dk
Australia (02)9450-2066 · Austria 0043-1-8657400 · Brazil (011)5182-8166 · Canada (514)695-8225 · China (86) 1068029906
Czech Republic 02-67021100 · Finland (0)9-755 950 · France (01)69906900 · Germany 06103/908-756 · Hong Kong 25487486 · Hungary (1)2158305
Ireland (01) 450 4922 · Italy 02 57 68061 · Japan 03-3779-8671 · Republic of Korea (02)3473-0605 · Netherlands (31)318 559290 · Norway 66771155
Poland (22)858 9392 · Portugal (1)4711453 · Singapore (65) 377- 4512 · Slovak Republic 421 7 544 307 01 · Spain (91)3681000 · Sweden (08)4498600
Switzerland 01/9436070 · Taiwan (02)7139303 · United Kingdom (0181)954-2366 · USA 18003322040
Local representatives and service organisations worldwide

BP 1311 – 14

99/11



---

Source Exif Data:

File Type                       : PDF
File Type Extension             : pdf
MIME Type                       : application/pdf
PDF Version                     : 1.3
Linearized                      : Yes
Create Date                     : 2000:01:25 12:20:43
Producer                        : Acrobat Distiller 4.0 for Windows
Title                           : Product Data Sheet: Sound Level Calibrator - Type 4231 (BP1311-14)
Creator                         : FrameMaker 5.5.6p145
Modify Date                     : 2001:06:18 09:43:52+02:00
Page Count                      : 4
Page Layout                     : OneColumn

EXIF Metadata provided by EXIF.tools