Hitachi RASC-4HNPE Service Manual page 248

10 Troubleshooting
Troubleshooting procedure
53
Alarm code
The inverter PCB (DIP-IPM) has a function of abnormality detection. This alarm is indicated when the inverter 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 inverter 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 exceeds +60deg.
Compressor stops
immediately. (Itc=1, 12)*
Restart operation.
Compressor stops
after few minutes.
(Itc=1)
(Itc=21)*
Is the supply voltage
3N~ 400 V±10%?
Yes
Is voltage higher than
340V during operation?
Yes
Is voltage higher than
340V at any time?
Yes
Is the compressor
running current same as
operating current?
Yes
Is crankcase heater
ON?
Yes
?
N O T E
• *1): Perform the high voltage discharge work by referring to the paragraph
for the inverter PCB".
• *2): Regarding replacing or checking method for the inverter PCB, refer to the paragraph
Checking procedure for the inverter PCB".
• *3): Turn ON the number 1 switch of the dip switch DSW1 on DIP-IPM when restarting with disconnecting the terminals of the
compressor. After troubleshooting, turn OFF the number 1 switch of the dip switch DSW1 on DIP-IPM.
238 SMGB0091 rev.2 - 11/2015
Protection activation of inverter module (RASC-(4-6)HNPE)
Turn OFF power, disconnect U,
V, W from compressor terminals
and restart.
Does the protecting function
activate? *3)
It trips
Yes
Yes
Is heat exchanger
clogged?
No
No
No
No
* Refer to the item
stoppage (i)"
No
No
Is refrigerant
overcharged?
Is expansion valve of indoor unit
open-locked in cooling operation?
Is expansion valve of outdoor unit
open-locked in heating operation?
No
Is the discharge
pressure high?
No
Check the
compressor
Abnormal
Check the capacity and
wiring of the power source
"Cause of inverter
for details.
Yes
No
Yes
No
Yes
"RASC-(4-6)HNPE"
Normal
Failure of DIP-IPM.
Replace it.
Check the compressor.
Replace if faulty.
Remove clogging or replace
heat exchanger
Faulty DIP-IPM.
Replace it.
Restart operation after main
switch ON
Charge refrigerant correctly
Replace expansion valve
Check the compressor
Check stop valve and
expansion valve
Check clogging of the heat
exchanger
in section "10.4.2 Checking procedure
"RASC-(4-6)HNPE" in section "10.4.2