Fluke Vt02 Application Note

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You’ve got skill. You’ve got experience. Now you

have some groundbreaking new tools that give

you powers to document temperature issues, to be

several places at once, and to assess vibration

issues with just a touch.

Vibration is one of the earliest indicators of

machine health, and the Fluke 805 Vibration Meter

gives you a fast, foolproof and repeatable way to

do vibration screening. Simply touch the sensor to

motors, pumps, and other mechanical equipment

to measure overall vibration as well as test bearing

vibration.

Heat is the next major signal of trouble ahead.

Where there’s excess friction or resistance, there’s

heat. The VT02 Visual IR Thermometer is a ground-

breaking troubleshooting camera with an infrared

heat map. You get the complete picture of your

target with blended visual and thermal heat map

images, empowering you to find the exact location

of the issue.

When solving problems requires you to mea-

sure, monitor and record multiple readings from

multiple locations all at the same time, the Fluke

CNX wireless system connects you to problems

faster and more conveniently. Modules measure

ac voltage, ac current, temperature and more. And

you can see those live readings from

the wireless

CNX multimeter up to 20 meters away.

Alone, each of these tools offers fast, easy and

affordable new ways to solve problems.

Together,

they vastly expand your troubleshooting

powers.

Quickly find out what’s a problem and what’s not.

You’ll stay out of panic mode, be able to proactively

plan maintenance, and reduce overall downtime.

Application Note

Use your troubleshooting

superpowers for good

Fluke tools help you detect mechanical problems earlier in the failure curve and prevent

unplanned downtime.

Fluke VT02 Fluke CNX 3000 Wireless System Fluke 805

Visual IR Thermometer Vibration Meter

Unleash your full

troubleshooting powers

with innovative new tools

from Fluke.

2 Fluke Corporation Seven ways to use your troubleshooting superpowers for good

#1 Breaker panel problems

When you’re trying to track down problems in

dirty, wet, or electrically hazardous environments,

Fluke tools help you work more safely and save

you the time of repeatedly suiting up in full per-

sonal protective equipment (PPE).

In this case, you and two other technicians

suit up in full PPE and remove a 90-pound panel

cover that encloses a three-phase breaker panel.

Once it’s open, you scan the panel with the VT02

Visual IR Thermometer. Instead of taking dozens of

measurements with an IR thermometer to check for

issues, the VT02’s blended visual and thermal heat

map image instantly reveals a hot spot on breaker

#20. You capture the image along with the tem-

perature, date and time. Now you know you have

a problem, but you don’t know what’s causing it.

So next, you install a wireless CNX current

clamp to the circuit and re-secure the cover.

With the CNX radio turned on and the log button

pushed, you can now remove your PPE and moni-

tor the circuit from a safe distance, without gearing

up again. You’re free to walk away and do other

jobs while the modules continue to work for you.

Periodically you stop back to check real-time

readings with the CNX DMM, anywhere within

three meters of the panel. If nothing looks abnor-

mal at these spot checks, you can let the module

keep logging. (It can capture up to 65,000 sets

of min/max/avg readings over single or multiple

recording session.)

At the end of the shift you bring your laptop

over to the panel. With the CNX PC adapter plug-

ged into your PC, you wirelessly download the

logged readings directly into the SW3000 software

for analysis. You don’t have to reopen the cabinet

door or suit back up in your PPE.

As you analyze the data, you notice some

unusual surges in the current readings, which

occur intermittently over the day. Using the

time-stamped measurements you can now track

the problem down to a particular process that

switches on at those times. If you have multiple

CNX modules available for troubleshooting you can

monitor multiple points simultaneously and isolate

the problem much faster. But you can also use

single clamp modules and some repetitive testing

to find the source of the problem.

You suspect a motor that’s connected to that

circuit. Scanning that motor with the Fluke 805

reveals a bearing problem. Crest Fact+ technology

allows you to make accurate high-frequency

measurements to diagnose bearings. The four-

level severity scale rates the bearing “unsatisfac-

tory.” You remove it from service and replace the

bearing.

The next day, you recheck the motor with the

Fluke 805. Now it gets a “good” rating. When you

rescan the breaker panel with the VT02, you see

no hot spots on breaker #20 or anywhere else on

the panel. All other temperatures are now within

the normal range.

Here are just a few scenarios

that demonstrate how you can

use your new powers.

You’ll feel like a superhero.

Fluke VT02 25 % blend 50 % blend 75 % blend

Visual IR Thermometer Blended visual and thermal images eliminate guesswork.

3 Fluke Corporation Seven ways to use your troubleshooting superpowers for good

#2 Tracking down motor trouble

During your regular scheduled maintenance check

of critical motors in your plant, you perform a

vibration screening using the Fluke 805 Vibration

Tester. You find a motor that gives an indication of

an internal issue. You connect three wireless CNX

modules and begin monitoring all three phases of

motor current over the course of the week.

While the modules are collecting data, you

make a quick check for hot spots from time to time

with the VT02. Early in the week, you see that the

motor has begun to generate moderate heat at the

drive shaft. By the end of the week, the sides of

the motor appear hot. A quick check with the 805

shows that overall vibration is satisfactory and the

bearings are rated “good” on the severity scale.

Ruling out a mechanical issue, it’s time to search

for an electrical problem.

At the end of the week, you wirelessly down-

load the logged data to the SW3000 software on

your laptop using the Fluke CNX PC Adapter. You

discover from the data that the motor current is

high based on its load. You suspect that this exces-

sive current draw is due to an internal problem in

the motor. It may be time to take the motor offline

and do an insulation resistance test. You can use a

Fluke insulation resistance tester to test the wind-

ing insulation to ground and discover the problem.

You remove the motor from service and replace it

with a different motor while the bad motor is refur-

bished and rewound at a rebuild facility.

#3 Troubleshooting a rooftop

HVAC system

A rooftop air conditioner trips the breaker and

shuts down after only 30 minutes of operation.

Yet at restart, it operates within manufacturer’s

specifications. After it has been running a few

minutes, you check bearings, belts and couplings

for vibration using the Fluke 805. All components

are rated “satisfactory” on the severity scale.

Next you use the VT02 to check around for hot

spots. You check the motor itself to see if the sides

are hot, which would implicate the windings. You

then check the output of the belt the motor is driv-

ing. While you didn’t see vibration on the motor

side with the Fluke 805, the belt may have insu-

lated the motor from a mechanical problem at the

fan. Possibly the fan bearing is damaged, putting

strain on the motor.

You use the VT02 to check motor functions,

driven-device functions (such as the fan bearing)

and the output temperature of the cooled, moving

air. Nothing looks excessive, so it’s time to do some

monitoring.

With the unit continuing to operate, you attach

wireless CNX current modules to the incoming

power legs and a wireless CNX current clamp

module at the load.

Start with an inrush test on motor startup. Use

the “inrush” function on the flex clamps to see if

inrush current to the motor falls within range for

the motor ratings. If the measurement is accept-

able you can then connect multiple current and

voltage modules, letting them log

readings from

startup until the system shuts down.

The wireless modules give you a way to watch

for issues without somebody “living” on the roof.

You can check the live readings from a comfortable

position within 20 meters/60 feet of the modules.

Meanwhile, each module collects time-stamped

measurements, the critical information you’ll need

for a proper diagnosis.

When you download the data later, it reveals

a

large current variance, an increase in amperage,

and an over-heating condition, all with time

stamps. You diagnose a drive component issue.

The repair can be completed after hours. The

system is back up and running quickly, and every-

one keeps cool.

4 Fluke Corporation Seven ways to use your troubleshooting superpowers for good

#4 Finding intermittent faults on a food

processing line

When operating conditions limit access, such as

complex production lines with moving parts and

rotating equipment, innovative Fluke tools can

help you make an assessment without contact.

Maybe there’s an intermittent fault on the line, but

you can’t isolate the problem. With the VT02, you

can stand at a safe distance and quickly scan a

relatively large area. Take a quick survey of the

various motors, drives, and mechanical equip-

ment to look for anything generating heat. When

you find a hot spot on a robotic arm, you capture

a blended visual and thermal heat map image you

can find the exact location of the hot spot along

with a temperature reading.

Now that you’ve narrowed it down, you only

need to access that one particular piece of equip-

ment. You get your opportunity when the line takes

a break. Because of the arm’s movement during

operation, you can’t make measurements with a

standard meter. So you secure CNX current mod-

ules to the arm at suspect power points.When the

line starts up again, you can monitor the readings

from a safe distance using the CNX multimeter.

You watch for a few minutes, but the problem

doesn’t occur while you’re standing nearby, so you

continue on to other jobs and let the CNX module

continue logging the data for you.

A fault occurs late in the shift and the CNX

module has captured a time-stamped event, which

you discover after you wirelessly download the

data to your PC. It’s time to pull out the big guns

and request that a technician perform a full

vibration analysis of the robotic arms using a

Fluke 810 Vibration Meter.

#5 Intermittent motor overload

To troubleshoot an intermittent motor overload

condition—once you’ve ruled out a faulty motor—

start by connecting the CNX wireless voltage

module to the motor starter within the motor con-

trol center and the CNX wireless current module to

the field disconnect switch adjacent to the motor.

Then, while the motor is operating,

verify and

view the supply voltage and current

with the CNX

multimeter, while checking temperature with the

VT02, to help you narrow down the variables. If

the supply voltage drops, the power company has

a problem that’s overworking the motor. If cur-

rent draw is excessive, there may be a mechanical

problem with the motor, which you can quickly

check out with the Fluke 805 to detect overall

vibration or to find a faulty bearing. The VT02 will

help you identify any areas generating excess

heat. If there’s heat, but you’re not detecting vibra-

tion, perhaps the problem is from the load the

motor drives. Check to see if vibration in the load

is causing the motor to work too hard.

If you can’t identify the problem on the spot, just

leave the modules in place to log data. Later you

can download it for full review and evaluation to

isolate the source of the problem.

5 Fluke Corporation Seven ways to use your troubleshooting superpowers for good

#6 Diagnosing a three-phase motor

without suiting up

If you have a big motor you need to diagnose, such

as a 408 V AC 200 HP motor with a wye-delta, you

can use the CNX wireless system to test without

needing personal protective equipment (PPE). Dis-

connect power before you open the motor control

center (MCC) cabinet. Then connect three hard jaw

clamp CNX current modules—one per phase—to

measure three-phase current. Or, connect three

CNX voltage modules or use a combination of both.

Close the MCC cabinet, re-apply power and start

the motor. Now you can take all the measure-

ments without PPE. These tests will show you if

the motor is working too hard electrically. If it is,

you still need to find out why. The 805 will show

you mechanical problems. The VT02 will reveal

hot spots. Heat with no vibration could help verify

internal electrical faults.

#7 Pump occasionally blows a fuse

You have a pump motor that occasionally blows a

fuse, and you can’t find an obvious cause. Set up

a CNX current module, securing it to an electrica

l

disconnect and feeding the module wires through

a ½ inch knockout. Now you can monitor the amps

wirelessly and discover what’s causing the fuse

to blow—or at least you’ll know the timing of the

event. By the next morning, you’ll know the exact

time when the event occurs.

You may find that at the time of the fault,

multiple processes start up, creating an excessive

load on a branch circuit, causing a nuisance trip.

Resizing the breaker or redistributing the loads

may solve this type of problem. It could also be

a loose connection. The VT02 is helpful for finding

those. Check for hot spots that signal loose con-

nections in the circuit, possibly at one of the loads.

Fluke. Keeping your world

up and running.®

Fluke Corporation

PO Box 9090, Everett, WA 98206 U.S.A.

Fluke Europe B.V.

PO Box 1186, 5602 BD

Eindhoven, The Netherlands

For more information call:

In the U.S.A. (800) 443-5853 or

Fax (425) 446-5116

In Europe/M-East/Africa +31 (0) 40 2675 200 or

Fax +31 (0) 40 2675 222

In Canada (800)-36-FLUKE or

Fax (905) 890-6866

From other countries +1 (425) 446-5500 or

Fax +1 (425) 446-5116

Web access: http://www.fluke.com

©2013 Fluke Corporation.

Specifications subject to change without notice.

Printed in U.S.A. 03/2013 4331701A A-EN

Modification of this document is not permitted

without written permission from Fluke Corporation.

0.0

32.2

23.5

29.4

V AC

A AC

A AC

A AC

Auto

1

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INRUSH

Hz

L1 L2 L3

L1

DMM

L2

L3

Motor power

Cabinet

INRUSH

Hz

INRUSH

Hz

INRUSH

Hz

0.0

32.2

23.5

29.4

V AC

A AC

A AC

A AC

Auto

1

2

3

Determining current unbalance