Mitsubishi Electric Q172DCPU User Manual page 159

6 INSPECTION AND MAINTENANCE
Remove all modules other than the
power supply module from the base
unit.
Install all modules that removed from
the base unit to the base unit.
Check the sum of internal current
consumptions of the modules that
comprise the system.
current exceed the rerated
output current of the power
H/W fault
Check operation in the order starting
with the minimum system.
If the module will not work, explain
the error symptom and get advice
from out sales representative for the
modules with failure.
1)
Does "POWER"
LED turn on?
YES
Does the total
supply module?
NO
The base unit that includes the
NO
corresponding power module is faulty.
(Replace it with a normal base unit.)
Does "POWER"
LED turn on?
NO
H/W fault
Explain the error symptom and get
advice from out sales representative.
Reexamine the system configuration
YES
to make the total current less than the
rated output current of the power
supply module.
NO
Does "POWER"
LED turn on?
6 - 16
YES
YES
END