Mitsubishi Electric PQHY-P120THMU-A, Service Handbook

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[
IX
Troubleshooting ]
- 244 - HWE09080 GB
1. Error Code
Open phase
2. Error definition and error detection method
Œ
An open phase of the power supply (L1 phase, L2 phase) was detected at power on.
Œ
The L3 phase current is outside of the specified range.
The open phase of the power supply may not always be detected if a power voltage from another circuit is applied.
3. Cause, check method and remedy
4102 (THMU-A)
Cause Check method and remedy
(1) Power supply problem
Œ
Open phase voltage of the power supply
Œ
Power supply voltage drop
Check the input voltage to the power supply terminal block TB1.
(2) Noise filter problem
Œ
Coil problem
Œ
Circuit board failure
Œ
Check the coil connections.
Œ
Check for coil burnout.
Œ
Confirm that the voltage at the CN02 connector is 188 V or
above.
(3) Wiring failure Confirm that the voltage at the control board connector CNAC is
188 V or above.
If the voltage is below 188V, check the wiring connection between
the noise filter board CN02 and control board CNAC.
Confirm that the wiring between TB23 and INV board SC-T is put
through CT3.
(4) Blown fuse Check that F01 on the control board is not blown.
->If a blown fuse is found, check for a short-circuiting or earth fault
of the actuator.
(5) CT3 failure Replace the inverter if this problem is detected after the compres-
sor has gone into operation.
(6) Control board failure Replace the control board if none of the above is causing the
problem.