Samsung RM255BABB Manual Do Utilizador

1)  As shown in the Figure, C/F, C/R FAN are connected to the CN75 connector, and FAN MOTOR consists of

ND, VCC, FG.

2) If you intend to operate the C/F-FAN or C/R-FAN according to a certain condition in the MAIN PCB, which

controls the refrigerator, follow the instructions below.

3) For example, to operate C/F-FAN, a 5V voltage comes out of MICOM #6 first. Then, the 5V voltage is input to

IC75 #1 PIN, and the #18 PIN has a changed electric potential from OV to GND.

4) 12V is connected to CN76  , and input to C/F-FAN Vcc. FAN MOTOR GND is connected to IC75 #18 PIN

through CN76  .

5) Thus, with the IC75 #18 PIN changed to GND by the signal from MICOM#6 PIN, the 

FAN MOTOR will be operated in the order 12V 

CN76

C/F -FAN Vcc  

C/F-FAN GND  

CN76

IC75 #18 PIN

GND.

6)  Here, with normal operation of the FAN MOTOR, a square wave is generated in MOTOR FG, and this wave is

input as follows, MOTOR FG 

CN76

R413

MICOM #8.

7) Using this FG signal, it can be determined whether the FAN MOTOR is operating normally, and in case of FG

signal errors, FAN motor errors are detected to use as refrigerator error data.

8) When the MICOM #6 signal changes to 0V again, IC75 # 1 PIN is OFF, and IC75 #18 PIN is

OFF. Thus, current cannot flow, and the FAN MOTOR will stop..

The principle of operation is equally applied to the C/F
and C/R FAN, and the BOX FAN uses the same
specification.

BOX     FAN     SPEC

12V / 0.2A

107

MICOM STATUS

IC75 INPUT 

IC75 OUTPUT

C/F-FAN

C/R-FAN

ON

OFF

ON

OFF

#6  5V 

#6  0V 

#4  5V 

#4  0V

#1  5V 

#1  0V 

#4  5V

#4  0V

#18 GND(0.8V) 

#18 11~12V

#15 GND(0.8V) 

#15 11~12V

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