Midea MHC-96HWD1N1(A) Service Manual page 42

R410A Full DC Inverter Split Duct Type Technical Manual
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E5: Voltage error
E5: Voltage error
Voltage of power supply is too high or
too low (the normal voltage between A
and N (B and N, C and N) should be
163V~268V)
No
Check the high voltage circuit. Whether
the compressor is short circuit①, fan
motor is short circuit②, inverter module
is output error③, etc.
No
Outdoor main control
board is damaged
Note:
1. How to check whether the compressor is short circuit①:
The normal resistance value of inverter compressor among U V W is 0.7~1.5Ω, and infinity to earth. If the
resistance value is out of the range, the compressor is abnormal.
2. How to check whether the fan motor is short circuit②:
The normal value of DC fan motor coil among U V W is less than 10Ω, and the value of AC fan motor coil
is from a few ohm to hundreds of ohm for different fan motor model. If the measured value is 0Ω, the fan
motor is short circuit.
3. How to check whether the inverter module is output error③:
Dial the multimeter to diode file, black pen on P and red pen respectively on U,V,W, if the multimeter
displays 0.4~0.7 V, it is normal; Red pen on N, black pen respectively on U,V,W, if the multimeter displays
0.4~0.7 V, it is normal. Satisfying the above two conditions at the same time indicates that the inverter
module has no problem.
41
Yes
Provide normal power supply
Replace the inverter module
Yes
or repair related parts
Replace the outdoor
main control board
MCAC-UTSM-201503