Troubleshooting Guide
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Only training and service purposes.
231
Inverter Compressor DC
Link Low Voltage
Error
No.
Error Type
Error Point
Main Reasons
DC Voltage isn't charged
after starting relay on
1. DC Link terminal misconnection/terminal
contact fault
2. Starting relay damage
3. Condenser damage
4. Inv. PCB damage
(DC Link voltage sensing part)
5. Input voltage low
n
Error Diagnosis and Countermeasure Flow Chart
Is input voltage normal?
No
Yes
Recheck power and installation condition
Yes
Check
R~S/S~T/T~R phase voltage is 380V 10%
R~N/S~N/T~N phase voltage is 220V 10%
→
Check connection condition and wiring if power is
abnormal
Are there any power wire
connections normal?
No
Yes
1. Check R/S/T/N wiring conditions
→
Rewire them if abnormality found.
Is Inv. PCB
normal?
No
Check Inv. PCB IPM normality.
→
Replace Inv. PCB if abnormality found.
Is bridge diode normal?
No
1. Check joining condition of bridge diode and heatsink
2. Check bridge diode
→
joining again or replacing bridge diode
if abnormality found
Yes
Yes
Is Inv. PCB
bridge diode joining condition normal?
No
Check joining condition of Inv. PCB and bridge diode
→
joining again if abnormality found
Yes
Is DC_Link Wire connection
condition normal?
No
1.Check Inv. PCB P,N connector
connection condition
2.Check Inv. PCB P,N connector
connection condition
3. Check wire disconnection and wiring
→
Reassemble if abnormality found
