innovair Inverter FLEX24 DEV24H2R18, Service Manual

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Possible reason:
Current detection (or current sensor) sampling circuit element is abnormal.
Drive chip compressor current sampling AD terminal is badly welded or short-circuited.
Troubleshooting ：
PC Current detection
(or current sensor)
circuit error
Replace the drive
board.
3.4.22 “PL” Bus Low-Voltage Protection
Error display: ODU mainboard LED displayer
Error judgment condition and method:
When compressor is running and there is no other malfunction, if busbar voltage is lower than the set value
for low voltage protection, then it can be judged that bus low-voltage protection occurs. System will shut down for
protection.
Possible reason:
Voltage of power grid is abnormal.
Drive board busbar voltage sampling circuit element is damaged or drive board busbar voltage sampling AD
terminal is abnormal.
Troubleshooting ：
PL Bus low-voltage protection
Grid voltage is normal or not ?
Normal
protection
Replace the dr ive
board .
YES
NO
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SERVICE MANUAL