Manual

Maintenance and Troubleshooting
4-1
C
HAPTER
4
Maintenance and Troubleshooting
Routine maintenance should include the periodic checking of all electrical power
connections into and out of the Power Module. The Power Module, its enclosure, and
the PMI rack should be kept clean. Any air filters should be checked and cleaned or
replaced as needed. Adequate cooling air must be provided to the Power Module
whenever the unit is operating.
4.1 Recommended Test Equipment
An oscilloscope can be used to check the current feedback and the output voltage
waveform. An isolated or portable volt/ohmmeter is also needed for continuity and
ground checks and to test output voltage.
The oscilloscope should have an impedance of at least 8 M ohms, a 1:10 probe for
signal circuits, and a 1:100 probe for power circuits. An ungrounded oscilloscope with
differential inputs and two 1:10/1:100 probes is recommended. All measuring devices
that are AC line powered must be connected through an isolation transformer. There
must be no ground connection through the transformer.
!
ATTENTION:
Equipment is at line voltage when AC power is connected
to the Power Module. All phases of the AC power line and control power
must be disconnected from the Power Module before it is safe to touch
any internal parts of this equipment. Failure to observe this precaution
could result in severe bodily injury or loss of life.
ATTENTION:
!
ATTENTION:The Power Module’s common is not isolated from earth
ground. The test instruments used to measure power module signals
must be isolated from ground through an isolation transformer unless
they are battery powered. Failure to observe this precaution could result
in bodily injury.
!
ATTENTION: