Application Note

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.