Trouble Treatment When The Main Power Breaker Is Tripped - Mitsubishi Electric PU(H)Y-P250YGM-A Service Handbook

[ IX Troubleshooting ]

(3) Trouble treatment when the main power breaker is tripped.

Items to be checked
[1] Perform Meg check between the
terminals on the power terminal
block TB1.
[2] Turn on the power again and
check again.
[3] Turn on the outdoor unit and check
that it operates normally.
Phenomena
Zero to several ohm, or Meg failure Check each part in the main inverter cir-
1) Main power breaker trip
2) No remote control display
1) Operates normally without trip-
ping the main breaker.
2) Main power breaker trip
- 160 -
Remedy
cuit.
*Refer to "Simple checking Procedures
for individual components of main in-
verter circuit".
Diode stack
IPM
Rush current protection resistor
DC reactor
i) The wiring may have been short-
circuited. Search for the wire
that short-circuited, and repair it.
ii) If item i) above is not the cause of
the problem, the compressor
may have a problem.
A compressor ground fault can be con-
sidered. Go to (2)-[2].