Error Codes [4220, 4225, 4226] Detail Code 108 (Tlmu) - Mitsubishi Electric R410A Service Handbook

[7-5 Error Code Definitions and Solutions: Codes [4000 - 4999] ]
7-5-10

Error Codes [4220, 4225, 4226] Detail Code 108 (TLMU)

1. Error code definition
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
Find out if there was a (momentary) power failure.
Check whether the power voltage is 188V or less across all phases.
(2) Voltage drop detected
4220
P72, P96, P120, P144 models
Check the voltage between the tab terminal TB-P and TB-N on the INV board while the inverter is stopped.
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 CN72C on the control board.
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.
Replace the noise filter board if no problems are found.
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.
P168 model
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 CN72C on the control board.
3) Check the coil connections (L1 - L3) and coil burnout.
4) Check the resistance of the diode stack. Refer to the following page(s). [8-9-15 Troubleshooting Problems with Diode
Stack](page 274)
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 the following page(s). [8-9-15 Troubleshooting Problems with Diode
Stack](page 274)
4) Check the in-rush current resistor value. Refer to the following page(s). [8-9-13 Simple Check on Inverter Circuit
Components](page 272)
5) Replace the noise filter board.
4225
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 CN72C on the control board.
2) Check the coil connections (L1 - L3) and for coil burnout.
3) Check the wiring connections between noise filter board, inverter board, and fan board.
Replace the noise filter board, if no problems are found.
If the problem recurs after replacing the noise filter, replace the Fan board.
Check the following items if the voltage is below 253V.
4) Check the CNVDC connector connection.
HWE14080
Go to (3).
Check the following items if the voltage is below 253V.
Go to (3).
Go to 3).
- 174 -
Check the
GB