Mitsubishi Electric PURY-P120Y(T)HMU-A, Service Handbook

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[
IX
Troubleshooting ]
- 195 - HWE0803A GB
1. Error Code
Open phase
2. Error definition and error detection method
ΠAn open phase of the power supply (L1 phase, L2 phase) was detected at power on.
ΠThe 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.
P72 model
Confirm that the wiring between TB23 and INV board SC-T is put
through CT3.
P96 and P120 models
Confirm that the wiring between the coil L3 and TB23 is put
through ACCT3.
(4) Blown fuse Check F01 on the control board, F4, and F5 for a blown fuse.
->If a blown fuse is found, check for a short-circuiting or earth fault
of the actuator.
(5) CT3 failure P72 model
Replace the inverter if this problem is detected after the compres-
sor has gone into operation.
P96 and P120 models
Replace the ACCT3 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.