Cetron TMF Series - Fan Motor Circuit of the Freezing Chamber; Sensor Resistance (R;T)

Service Manual_2017-V1
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The fan in the freezing chamber is running when the compressor is operating. Check 12V and FAN to see
if there is a voltage of 12V. When in normal operation, the fan is in low level and the voltage between 12V
and FAN is more than 11V. If there’s no voltage when the compressor is in operation, fan motor or electric
control panel can be replaced.
10.4 Fan motor circuit of the freezing chamber
10.5 Refrigerator fan motor circuit (None)
10.6 Condenser fan motor circuit(None)
10.7 Damper motor circuit(None)
10.8 Sensor resistance(R/T)
Tx(℃) R（KΩ） Tx(℃) R（KΩ） Tx(℃) R（KΩ） Tx(℃) R（KΩ） Tx(℃) R（KΩ）
-30
33.81
-15
14.31
0
6.495
15
3.141
30
1.617
-29
31.85
-14
13.55
1
6.175
16
2.999
31
1.55
-28
30.01
-13
12.83
2
5.873
17
2.865
32
1.486
-27
28.29
-12
12.16
3
5.587
18
2.737
33
1.426
-26
26.68
-11
11.52
4
5.315
19
2.616
34
1.368
-25
25.17
-10
10.92
5
5.06
20
2.501
35
1.312
-24
23.76
-9
10.35
6
4.818
21
2.391
36
1.259
-23
22.43
-8
9.82
7
4.589
22
2.287
37
1.209
-22
21.18
-7
9.316
8
4.372
23
2.188
38
1.161
temperature.
The characteristic that resistance value reduces as the temperature increases is deemed to have
negative slope or negative temperature coefficient (NTC), and such thermistor is called as NTC thermistor.
The resistance value changes sensitively with temperature and typically changes 7% ~ 3% per degree
centigrade. Sensor used in the refrigerator is NTC thermistor.
There is following computing formula for the sensor:Sampling voltage / reference voltage =
R1 / (RNTC + R1)
AD value / reference AD value = R1 / (RNTC + R1)