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Self-diagnosis function
Inv. PCB IPM Fault occur
Error
No.
Error Type
Error Point
Main Reasons
IPM self protection circuit
activation
(Overcurrent/IPM overheat-
ing/Vcc low voltage)
1.Over current detection at Inverter compres-
sor(U,V,W)
2.Compressor damaged (insulation dam-
aged/Motor damaged)
3.IPM overheating
(Heat sink disassembled)
4.Inverter compressor terminal disconnected
or loose
5.Inverter PCB assembly damaged
6.ODU input current low
n
Error diagnosis and countermeasure flow chart
Are the resistance
Between each phase and
insulation resistance of Inverter
compressor normal?
No
Yes
Recheck power and installation condition
Yes
1. Check resistance between each terminal of
compressor.(Refer to the right side tables.)
2. Check insulation resistance between
compressor terminal and pipe (over 50 m)
→
Replace compressor if abnormality found
Are there any power wire
connections normal?
No
Yes
1. Check L1(L)/L2(N) wiring condition
→
Rewire them if abnormality found
Is Inv. PCB
normal?
No
Check Inv. PCB IPM normality.
→
Replace Comp PCB assembly
if abnormality found.
Is compressor
Wire connection
condition normal?
No
1. Check Inv. PCB U,V,W connector
connection condition
2. Check wire disconnection and wiring
3. Check compressor terminal connection
condition(bad contact)
→
Reassemble if abnormality found
1.Check Inv. PCB P,N connector
connection condition
2. Check wire disconnection and wiring
→
Reassemble if abnormality found
Yes
Yes
Is DC_Link Wire connection
condition normal?
No
1.Check Inv. PCB IPM heat sink
joining condition
→
Reassemble if abnormality found
Yes
Is Comp IPM heat sink’s
joining condition normal?
No
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