Troubleshooting Guide
- 84 -
Copyright © 2018 LG Electronics Inc. All rights reserved.
Only training and service purposes.
n
Error diagnosis and countermeasure flow chart
Error No.
Error Type
Error Point
Main Reasons
711
Inv. CT Sensor Error
Micom input voltage
isn’t within 2.5V±0.3V
at initial state of power
supply
1. Input Voltage is abnormal (T-N)
2. ODU Inv. PCB damage (CT sensing part)
Are there any power wire
Connections normal?
No
1. Check R/S/T/N wiring conditions
2. Check noise filer wiring conditions
Rewire them if abnormality found
Check
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
Is input voltage normal?
Yes
1. Replace Inv. PCB
No
Is Inv. PCB
Assembly normal?
Yes
Yes
Recheck Power and
Installation Condition
* Inv. PCB assembly
* Measuring input voltage