Gree GMV6 DC Inverter VRF Units Service Manual
171
"P9" Loss of
Synchronization Protection
for the Inverter Compressor
The compressor drive
board operates improperly
Yes
Replace the compressor
drive board
No
Whether the U, V and W
phases of compressor wires are
connected properly?
Yes
No
Replace the
compressor
Whether the resistance
between the windings of each phase for the
compressor is normal (generally less than 2 ohms)?
Whether the resistance values are equal to each other? Is
grounding insulation of the phase windings of the
compressor normal (generally greater
than 2 megohms)?
Yes
Yes
Remove foreign matters
and open the valve
Whether the system is clogged
and whether the valve is open?
Yes
whether the system control valve
is normal (for example, whether balance valve
operates normally and whether the control
terminal is plugged properly)?
Yes
Whether other faults have
occurred at the same time (for example,
compressor startup failure (PJ), IPM module
protection (P6) and compressor over-current
protection (P5))?
Yes
The compressor is
damaged and should be
replaced
Whether the U, V and W
phases of compressor
wires are connected properly?
Yes