17
GENERAL
TROUBLESHOOTING TIPS
Prior to diving into a repair here a few tips if followed will make the job
easier and may prevent unnecessary damage to good components.
1.
First and foremost respect the voltages produced by the drive.
Always verify the presence of line voltage and bus voltage before
working on the unit. Also remember that some points in the drive
are referenced to the negative bus and are at bus potential even
though you may not expect it.
2.
Never power up a unit which has had power removed and is
suspected of being faulty. If a short circuit exists within the unit
applying power is likely to result in further damage. The safe
approach is to conduct the Static Test Procedures starting on page
23. The static tests check all high voltage components for short
circuits. The tests are relatively simple to make and can save money
and downtime in the long run.
3.
The safest method of conducting tests on the drive is with the motor
disconnected. In this way a faulty component that was overlooked
or the unfortunate slip of a test probe will generally result in a unit
trip instead of a component failure.
4.
Following the replacement of parts test run the unit with the motor
disconnected. Start the unit at zero speed and slowly ramp the
speed up until the speed is at least above 40 Hz. Monitor the phase
to phase output voltage on all three motor terminals to check for
balance. If balanced the unit is ready to be tested on a motor. If
not, further investigation is necessary.
5.
Never attempt to defeat fault protection devices within the drive.
This will only result in unwanted component damage and may
result in personal injury as well.
6.
Always use factory approved replacement parts. The unit has been
designed to operate within certain specifications. Incorrect parts
may effect the tolerence and result in further damage to the unit.
7.
Read the instruction and service manuals. A thorough
understanding of the unit is the best approach. If ever in doubt
consult the factory or an authorized repair center for assistance.