Inverter Output Related Troubles - Mitsubishi Electric PQHY-P72TYHMU-A Service Handbook

[ IX Troubleshooting ]
[THMU-A]

(2) Inverter output related troubles

Items to be checked
[1] (1) Disconnect the invert-
Check the INV er output wire from
board error the terminals of the
detection cir- INV board (SC-U,
cuit. SC-V, SC-W).
(2) Put the heat source
unit into operation.
[2] Disconnect the compres-
Check for sor wiring, and check the
compressor compressor Meg, and coil
ground fault or resistance.
coil error.
[3] (1) Disconnect the invert-
Check wheth- er output wire from
er the inverter the terminals of the
is damaged. INV board (SC-U,
(No load) SC-V, SC-W).
(2) Disconnect the short-
circuit connector from
CN6 on the INV
board.
(3) Put the heat source
unit into operation.
Check the inverter
output voltage after
the inverter output
frequency has stabi-
lized.
[4] Put the heat source unit
Check wheth- into operation.
er the inverter Check the inverter output
is damaged. voltage after the inverter
(During com- output frequency has sta-
pressor oper- bilized.
ation)
HWE09080
Phenomena
1) IPM/overcurrent breaker trip
Error code: 4250
Detail code: No. 101, 104, 105, 106,
and 107
2) Logic error
Error code: 4220
Detail code: No. 111
3) ACCT sensor circuit failure
Error code: 5301
Detail code: No.117
4) IPM open
Error code: 5301
Detail code: No.119
1) Compressor Meg failure
Error if less than 1 Mohm.
When no liquid refrigerant in the
compressor
2) Compressor coil resistance failure
Coil resistance value of 0.3 ohm
(20°C [68°F])
1) Inverter-related problems are de-
tected.
2) Inverter voltage is not output.
3) There is an voltage imbalance be-
tween the wires.
Greater than 5% imbalance or 5V
4) There is no voltage imbalance be-
tween the wires.
1) There is an voltage imbalance be-
tween the wires.
Greater than 5% imbalance or 5V
- 330 -
Remedy
Replace the INV board.
Replace the INV board.
Replace the INV board.
Normal
Check that no liquid refrigerant is
present in the compressor, and re-
place the compressor.
Replace the compressor.
Connect the short-circuit connec-
tor to CN6, and go to section [1].
Replace the INV board.
Replace the INV board.
Normal
*Reconnect the short-circuit con-
nector to CN6 after checking the
voltage.
If the problem persists, replace the
INV board.
If the problem persists after replac-
ing the above parts, go to section
[2].
GB