Hitachi RASC-10HNPE, Service Manual, Page: 249 / 306

10 Troubleshooting
Troubleshooting procedure
SMGB0091 rev.2 - 11/2015 239
10
Alarm code
53
Protection activation of transistor module (IPM) (RASC-(8/10)HNPE)
IPM has a function of abnormality detection. This alarm is indicated when the transistor module detects the abnormality 7
times in 30 minutes including 7. Retry operation is performed up to the occurrence of 6 times.
Conditions:
• The abnormal current such as short circuited, grounded or the overcurrent occurs at the transistor module.
• The temperature at inverter module increases abnormally.
• The control voltage decreases.
• The angle difference between the shaft in compressor and the shaft in the control program e60deg.
Are the power wires
passed through CT
(inverter element)?
No
Failure of PCB4.
Replace it.
No
Restart operation.
Yes
Check the
compressor
Normal
Check the compressor.
Replace if faulty.
Abnormal
Check IPM (*1)(*2)
Apply silicon to cover
entirely the space
Faulty PCB4.
Replace it.
Check the compressor
Is high pressure increased?
Check pressure and
refrigerant cycle
Check clogging for heat
exchanger
* Refer to the item “Cause of inverter
stoppage (i

)” for details.
Compressor stops
after few minutes.
(Itc=21)*
Compressor stops
immediately.
(Itc=1, 12)*
Turn OFF power,
disconnect U, V,
W from compressor
terminals and restart.
Does the protecting
function activate? *3)
Pass the power wires
through CT
Yes
No
Replace IPM.
Check PCB4
Normal
Replace IPM and PCB4.
Abnormal
Abnormal
Is the space
between the transistor
module and radiation
fins entirely covered
by silicon?
Normal
Yes
Is heat exchanger
of clogged?
Yes
Remove clogging or replace
heat exchanger
No
?
N O T E
• *1): Perform the high voltage discharge work by referring to the paragraph “RASC-(8/10)HNPE” in section “10.4.2 Checking procedure
for the inverter PCB”.
• *2): Regarding replacing or checking method for the inverter PCB, refer to the paragraph “RASC-(8/10)HNPE” in section “10.4.2
Checking procedure for the inverter PCB”.
• *3) Turn ON the number 1 switch of the dip switch DSW1 on PCB4 (inverter) when restarting with disconnecting the terminals of the
compressor. After troubleshooting, turn OFF the number 1 switch of the dip switch DSW1 on PCB4.