V6-i VRF 50/60Hz 
    73 
Part 
6 - Diagnosis and Troubleshooting
 
 Procedure 2.2.5
 
The phase sequence of the 3-phase 
power supply
 
is incrorrect
1
 
Exchange any two of the 3 phase wires 
Some power supply terminals are loose
2
 
Ensure all supply terminals are securely 
fastened 
The power supply is abnormal 
Check the power supply equipment   
 
Notes:   
1.  The  A,  B,  C  terminals  of  the  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.