Mitsubishi Electric City Multi CMB-P1016NU-G, Service Handbook

Page: 300 / 349

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[
IX
Troubleshooting ]
Items to be checked Phenomena Remedy
[3]
Check whether
the inverter is
damaged.
*Perform this
check if an error
occurs immedi-
ately before or
after turning on
the compressor. Perform the following:
(1) Reconnect the connector
that was removed in section
[1].
(2) Disconnect the compressor
wiring.
(3) Turn on SW1-1 on the com-
pressor INV board.
Operate the outdoor(heat
source) unit after above
steps.Check the inverter output
voltage.
*It is recommended to use the
tester used in the 9.[4] -5-(5)
IPM troubleshooting when
checking the inverter output volt-
age.
Measure voltage when the com-
pressor inverter output frequen-
cy is stable.
1) IPM/overcurrent breaker
trip
(4250 Detail code No.
101, 102, 103, 104, 105,
106, and 107)
Refer to item [5] for inverter circuit
trouble.
2) The voltage imbalance
across all wiring
There is a high possibility
of an inverter circuit error
if the voltage imbalance
across all wiring is great-
er than the larger of the
values represented by
5% or 5V.
3) No voltage imbalance
across all wiring
See item [2].
Proceed to item [5], however if
there is no problem in section [2].
Replace the compressor if there is
no problem in section [5].
[4]
Check whether
the inverter is
damaged.Per-
form this check
if an error oc-
curs during op-
eration. Turn on the outdoor(heat
source) unit.
Check the inverter output volt-
age.
*It is recommended to use the
tester used in the 9.[4] -5- (5)
IPM troubleshooting when
checking the inverter output volt-
age.
*Measure voltage when the
compressor inverter output fre-
quency is stable. 1) The voltage imbalance
across all wiring
There is a high possibility
of an inverter circuit error
if the voltage imbalance
across all wiring is great-
er than the larger of the
values represented by
5% or 5V.
Refer to item [5] for inverter circuit
trouble.
2) No voltage imbalance
across all wiring
See item [2].
Proceed to item [5], however if
there is no problem in section [2].
Replace the compressor if there is
no problem in section [5].