Haier AFD631 Series, Руководство по обслуживанию, Страница: 29 / 35

ELECTRICAL CONTROL PRINCIPLE
Electrical control principles of the refrigerator
8.1 Overview
Electrical control principle of CFE/AFL/AFD refrigerators
(1)
Fully air cooling design, controlled with a fixed frequency compressor;
(2)
The temperature in the fridge storage compartment is controlled by controlling the air door with the
fridge storage temperature sensor R;
(3) The temperature in the freezer storage compartment is controlled by controlling the power of the
compressor with the freezer storage temperature sensor F;
8.2 Main Control PCB of the Refrigerator
There are 4 connectors on the main control panel of CFE/AFL/AFD refrigerators.
Let’s describe these connectors:
CN1 is the connector for the sensors and the door switch. Its pins from the left to right are:
1: GND
2: +12V
3: Door switch signal. When the door is opened, GND and the signal wires are switch to
conduction. When the door is open, the wires are disconnected;
4-6: Null
7-8: Connected to the fridge storage temperature sensor. We can test the sensor with these two
wires. Its resistance in normal operation is between 6.35 and 3.88k Ω (correspond to 0
℃～
10
℃
). The
resistance at normal temperature is between 2.45 and 1.58k Ω (correspond to 20
℃～
30
℃
);
7-9: Connected to defrosting temperature sensor. We can test the sensor with these two wires.
Its resistance in normal operation is between 10.9 and 25.19k Ω (correspond to -10
℃～
-25
℃
). The
resistance at normal temperature is between 2.49 and 1.61k Ω (correspond to 20
℃～
30
℃
);
10-11: Connected to the freezer storage temperature sensor. Resistance test is the same as
the defrosting temperature sensor;
12: Null
CN2 is the connector for the LED lamps and display panel:
1: GND
2: +5V
3: Com
4: Com
5-6: Null
7: +12V
8: GND
CN3 is the connector for the power cables
1: Zero line
2: Live line
3: Compressor (between it and the zero line)
4: Null
5: Heating tube for defrosting. The resistance between it and the zero is 345
Ω ±10%
6: Null
CN4 is the connector for the air door and fan:
1: Feedback signal from the fan
2: GND of the fan
3: +12V of the fan
4: fan +12V
5-6: Null
7-9: Motor of the refrigeration air door
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