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4.3.4 Procedure
E1
The phase sequence of the 3-phase
power supply is incrorrect
1
Exchange any two of the 3 phase wires
Ensure all supply terminals are securely
fastened
Check the power supply equipment
No
Yes
Yes
Yes
No
No
Some power supply terminals are loose
2
The power supply is abnormal
Replace refrigerant system main PCB
Notes:
1. The A, B, C terminals of 3-phase power supply should match compressor phase sequence requirements. If the phase sequence is inverted, the compressor
will operate inversely. If the wiring connection of each outdoor unit is in A, B, C phase sequence, and multiple units are connected, the current difference
between C phase and A, B phases will be very large as the power supply load of each outdoor unit will be on C phase. This can easily lead to tripped circuits
and terminal wiring burnout. Therefore if multiple units are to be used, the phase sequence should be staggered, so that the current is distributed among the
three phases equally.
2. Loose power supply terminals can cause the compressors to operate abnormally and compressor current to be very large.
