LG MULTI V M ARNU07GTU 4 Series Svc Manual page 84

Troubleshooting Guide
Error No. Error Type
711 Inv. CT Sensor Error
n Error diagnosis and countermeasure flow chart
Are there any power wire
Connections normal?
Yes
Is input voltage normal?
Yes
Is Inv. PCB
Assembly normal?
Yes
Recheck Power and
Installation Condition
* Measuring input voltage
Error Point
Micom input voltage
isn't within 2.5V±0.3V
at initial state of power
supply
1. Check R/S/T/N wiring conditions
No
2. Check noise filer wiring conditions
Rewire them if abnormality found
Check
No
R~S/S~T/T~R phase voltage 380V±10%
R~N/S~N/T~N phase voltage 200V±10%
Check connection condition and wiring if power is abnormal
No
1. Replace Inv. PCB
* Inv. PCB assembly
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Main Reasons
1. Input Voltage is abnormal (T-N)
2. ODU Inv. PCB damage (CT sensing part)
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