Midea MHC-V6W/D2N8-B User Manual

M thermal Mono
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Midea M thermal Mono Service Manual
Principle of DC inverter
①Contactor is open, the current across the PTC to charge capacitor. After 5 seconds, the contactor closed.
②220-240V AC power supply change to DC power supply after bridge rectifier.
③The capacitor output steady power supply for inverter module P N terminals. In standby the voltage between P and N
terminal on inverter module is 1.4 time of AC power supply. When the fan motor is running, the voltage is 377V DC.
L0/L4 troubleshooting
Situation 1: L0 or L4 error appears immediately after the outdoor unit is powered-on
L0 / L4
Inverter module is damaged
1
Yes
Replace the inverter module
2
Notes:
1. Measure the resistance between each of U, V and W and each of P and N on the inverter module. All the resistances should be infinite. If any of them are
not infinite, the inverter module is damaged and should be replaced. Refer to Figure 4-2.5 to 4-2.7 in Part 4, 2.1 “Main PCBs for Refrigerant System,
Inverter Module”.
2. When replacing an inverter module, a layer of thermally conductive silica gel should be painted on the IPM module, IGBT, diode, brigde rectifier (on the
reverse side of the inverter module). Refer to Figure 4-4.2.
Figure 4-4.2: Replacing an inverter module
IPM
IGBT
diode
IGBT
diode
brigde rectifier
Power
supply
(220V)
L
N
Bridge
rectifier
PTC
Contactor
Inductor
Capacitor
Inverter
module
U
V
W
Comp
ressor
P
N
PFC
○
3
○
2
○
1
Midea CAC Confidential

Midea MHC-V6W/D2N8-B Specifications

General

Brand	Midea
Model	MHC-V6W/D2N8-B
Category	Air Conditioner
Language	English