Mitsubishi Electric PQHY-P72ZLMU-A Service Handbook page 267

[ IX Troubleshooting ]
1. Error Code
4102
Open phase
2. Error definition and error detection method
An open phase of the power supply (L1 phase, L2 phase) was detected at power on.
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
Cause
(1) Power supply problem
Open phase voltage of the power supply
Power supply voltage drop
(2) Noise filter problem
Coil problem
Circuit board failure
(3) Poor connector contact (faulty connector
insertion)
(4) Wiring failure
(5) Blown fuse
(6) CT3 failure
(7) Control board failure
HWE15150
Check method and remedy
Check the input voltage to the power supply terminal block TB1.
Check the coil connections.
Check for coil burnout.
Check that the voltage across TB11 and TB21 on the noise filter
board is 517.5 V or above.
Check the noise filter board connector (CN2) for proper connec-
tion.
Confirm that the voltage at the control board connector CNAC is
190 V or above.
If the voltage is below 190 V, check the wiring between the noise
filter CNTR, transformer box, and control board CNAC.
Check that the wiring between magnetic contactor (52C) terminal
No. 5 and SC-L3 is put through CT3 on the inverter board.
Check F01 on the control board, and F01 and F02 on the noise
filter board for a blown fuse.
If a blown fuse is found, check for a short-circuiting or earth fault
of the actuator.
Replace the INV board if this problem is detected after the com-
pressor has gone into operation.
Replace the control board if none of the above is causing the
problem.
- 258 -
GB