Mitsubishi Electric PUHY-P120YHMU-A, Service Manual

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[
IX
Troubleshooting ]
- 169 - HWE0804A GB
1. Error Code
Abnormal bus voltage drop (Detail code 108)
2. Error definition and error detection method
If Vdc 160V or less is detected during Inverter operation. (S/W detection)
3. Cause, check method and remedy
(1) Power supply environment
Check whether the unit makes an instantaneousstop when the detection result is abnormal or a power failure occurs.
Check whether the power voltage is 188V or less across all phases.
(2) Voltage drop detected
4220
P72 and P96 models
ΠCheck the voltage between the tab terminal TB-P and TB-N on the INV board while the inverter is stopped. -> Check the fol-
lowing items if it is 253V or above.
1) Confirm on the LED monitor that the bus voltage is above 160 V.
Replace the INV board if it is below 160 V.
2) Check the voltage at CN505 on the control board. ->Go to (3).
3) Check the coil connections (L1 - L3) and for coil burnout.
4) Check the wiring connections between the following sections
Between the noise filter board and INV board. Between the INV board and DCL. Between the INV board and C1.
Replace 72C if no problems are found.-> Check the following items if the voltage is below 253V.
1) Check the coil connections (L1 - L3) and for coil burnout.
2) Check the wiring between the noise filter board and INV board.
3) Check the connection to SC-P1 and SC-P2 on the INV board.
4) Check the in-rush current resistor value. Replace the INV board if no problems are found.
P120 model
Œ
Check the voltage between SC-P1 and IPM N terminals on the INV board while the inverter is stopped.
-> Check the following items if it is 253V or above.
1) Confirm on the LED monitor that the bus voltage is above 160 V.
Replace the INV board if it is below 160 V.
2) Check the voltage at CN505 on the control board. ->Go to (3).
3) Check the coil connections (L1 - L3) and coil burnout.
4) Check the resistance of the diode stack. ->Refer to [4] -6- (6).(page 251)
5) Check the wiring connections between the following sections:
Between the noise filter board and INV board. Between the INV board and C1.
Replace the noise filter board if no problems are found.
-> Check the following items if the voltage is below 253 V.
1) Check the connection to SC-P1 and IPM N on the INV board.
2) Check the wiring between the noise filter board and INV board.
3) Check the resistance of the diode stack. ->Refer to [4] -6- (6).(page 251)
4) Check the in-rush current resistor value. ->Refer to [4] -6- (4).(page 249)
5) Replace the noise filter board.
4225
Œ
Check the voltage at CNVDC on the Fan board while the inverter is stopped.
->Check the following items if it is 253 V or above.
1) Check the voltage at CN505 on the control board. ->Go to 3).
2) Check the coil connections (L1 - L3) and for coil burnout.
3) Check the wiring connections.
Replace 72C if no problems are found.
(P120 model: Replace the noise filter board.)
If the problem recurs after replacing 72C, replace the Fan board.
-> Check the following items if the voltage is below 253V.
1) Check the CNVDC connector connection.
(3) Control board failure
Confirm that a voltage of 208-230 VAC is applied to the connector CN505 on the control board during inverter operation.
->If voltage is absent, check the fuse F01. If no problems are found, replace the control board.
Refer to section -6- "Inverter (THMU-A)" under part [4] Troubleshooting Principal Parts for error codes related to the
inverter.(page 244)
4220
4225
(THMU-A)