Midea SMK-60/CGN8, Руководство по обслуживанию

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M‐Thermal Split
72 201909
Midea M‐Thermal Split Ser
vice Manual
Table 4‐4.2: Errors indicated on LED1/2
LED1/2 flashing pattern Corresponding error
Flashes 8 times and stops for 1 second, then repeats L0 ‐ Inverter module protection
Flashes 9 times and stops for 1 second, then repeats L1 ‐ DC bus low voltage protection
Flashes 10 times and stops for 1 second, then repeats L2 ‐ DC bus high voltage protection
Flashes 12 times and stops for 1 second, then repeats L4 ‐ MCE error
Flashes 13 times and stops for 1 second, then repeats L5 ‐ Zero speed protection
Flashes 15 times and stops for 1 second, then repeats L7 ‐ Phase sequence error
Flashes 16 times and stops for 1 second, then repeats
L8 ‐ Compressor frequency variation greater than
15Hz within one second protection
Flashes 17 times and stops for 1 second, then repeats
L9 ‐ Actual compressor frequency differs from
target frequency by more than 15Hz protection
Principle of DC inverter
① 220V AC power supply change to DC power supply after bridge rectifier.
② Contactor is open, the current across the PTC to charge capacitor, after 5 seconds the contactor closed.
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 310V DC. When the fan motor is running, the voltage between P and N terminal on
inverter module is 380V 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 4‐2.3 or 4‐2.5 in Part 4, 2.1 “Outdoor Unit PCBs”.
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 4‐4.1.
Power
supply
(220V AC)
L
N
Bridge
rectifier
PTC
Contactor
Inductor
Capacitor
Inverter
module
U
V
W
Compressor
P
N
PFC
○
3
○
1
○
2
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