Gree Ultra Heat GMV Multi VRF Heat Recovery Series Service Manual page 143

Ultra Heat GMV VRF Technical Service Manual_Heat Recovery Serial
the compressor from the drive board two minutes after the system is powered off. Make sure that it is
tested at least two minutes after the system is powered off. Then put the multi-meter to diode test
step.
b. Drive board 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.
PFC board 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 L1, L2 and L3 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 L1, L2 and L3 respectively and record readings of the multi-meter.
c. Analyzing: 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.
Drive board
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