9-7) Load Operation - Samsung RB1855SW Service Manual

Circuit Descriptions

9-7) Load Operation

1) Most of relays can control the compressor, heaters and several option functions.
2) For the compressor, #12 pin of MICOM signals HIGH(5V). This signal enters to #2 of IC03 and #15
of output terminal will be on and grounded. When the rely RY71 is switched to NO terminal a 115V
power is supplied to the compressor. If MICOM outputs LOW(0V), the compressor will stop.
3) If the RY71 is connected to NC, RY72 and 73 for defrost heaters will be on and corresponding heater.
According to the operation conditions of each load, the MICOM sends out a "HIGH" signal which is
applied to the DRIVERC(KID65003AP/S1P2655A03).
Then, the IC comes on and DC 12V goes into ground via the relay coil, which makes the core magnetic
and the relay contacts closed(becomes on).
When the relay contacts close, AC220V is supplied to the load for operation.
When the MICOM sends out a "LOW' signal, the relevant relay contacts open and then operation stops.
RELAY
Defrost Heater
COMP
on
on
off
off
Will be activated according to the signal from MICOM. Like the above block diagram, operation of F, R
defrost heater is determined by the operation of the relay for COMP.
When the comp relay becomes on, the compressor operates. At this time, the defrost heater goes off
because of the open circuited defrost heater cutting off power.
On the other hand, when the operation conditions of the defrost heater are met, the comp relay goes off
turning off the compressor and the defrost heater operates. At this time, both the compressor and the
defrost heater do not operate together under any conditions.
off
Comp Operation
on
Comp off, Defrost-Heater Off
on
Defrost-Heater On
off Comp Off, Defrost-Heater Off
Load
32
Remark
Defrost-Heater Power Off
Comp Power Off