LG ABNW85GB9A0 Svc Manual page 51

Part 4 Trouble Shooting
6.6 Troubleshooting Outdoor Error
CH 21 (DC Peak / Comp IGBTM Fault)
IGBTM Check
Judgment of the IGBTM part fault
Purpose
of PCB assembly.
■ Error diagnosis and countermeasure flow chart
Are there any power wire
connections normal?
Yes
Are the resistance
Between each phase and
insulation resistance of Inverter
compressor normal?
Yes
Is compressor
Wire connection
condition normal?
Yes
Is DC_Link Wire connection
condition normal?
Yes
Is Comp IGBTM heat sink's
joining condition normal?
Yes
Is Inv. PCB
normal?
Yes
Recheck power and installation condition
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Only for training and service purposes
Main Reasons
No
1. Check R/S/T/N Wiring Condition
→ Rewire them if abnormality found
1. Check resistance between each terminal of
compressor.(Refer to the right side tables.)
2. Check insulation resistance between
No
compressor terminal and pipe (over 50m)
→ Replace compressor if abnormality found
1. Check Inv. PCB U,V,W connector
connection condition
No
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
No
2. Check wire disconnection and wiring
→ Reassemble if abnormality found
1.Check Inv. PCB IGBTM heat sink
No
joining condition
→ Reassemble if abnormality found
Check Inv. PCB IGBTM normality.
No
(Refer to P.53)
→ Replace Comp PCB assembly if
abnormality found.
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1. Over current detection at Inverter
compressor(U,V,W)
2. Compressor damaged (insulation
damaged/Motor damaged)
3. IGBTM overheating
(Heat sink disassembled)
4. Inverter compressor terminal
disconnected or loose
5. Inverter PCB assembly damaged
6. ODU input current low
JBA068MAF
Temp 25°C
U-V 0.163 ± 7% Ω
V-W 0.163 ± 7% Ω
W-U 0.163 ± 7% Ω
LGE Internal Use Only
75°C
0.195 ± 7% Ω
0.195 ± 7% Ω
0.195 ± 7% Ω