GMV5 Home DC Inverter Multi VRF Units
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Attachment: How to check whether the IPM module is damaged:
â‘ Preparation: Find a digital multi-meter and switch it to the diode. Remove U, V and W
cables of the fan from the drive board two minutes after the system is powered off. Make sure that
it is tested two minutes after the system is powered off.
â‘¡Method: Use the black probe of the multi-meter to touch the place marked by P in the follow
picture and the red probe to touch places marked by U, V and W respectively and record readings
of the multi-meter. Use the red probe to touch the place marked by N and black probe to touch
places marked by U, V and W respectively and record readings of the multi-meter.
â‘¢Analysis: If the reading ranges between 0.3 V and 0.7 V in the above-mentioned six
scenarios, the IPM module is normal. If the reading is 0 in one or multiple scenarios, the IPM
module is damaged.
Inverter fan drive board IPM module over-temperature fault (ODU fault code H8)
High voltage protection for the DC bus of the inverter fan’s drive board (ODU fault
code HH)