12-11) Load Drive Circuit - Samsung RSE8KPAS Service Manual

Circuit Descriptions

12-11) Load Drive Circuit

1) The control of load in the system is accomplished by the main PCB.
2) Most of relays or SSRs can control the compressor, refrigerator/freezer defrost heater, and several option
functions.
3) For the compressor, #37 pin of micro processor signals High (5V). This signal enters #8 pin of IC73 and #11 of
output terminal which have base and collector functions of IC73 turns on and connects the GND. Relay 72 will
be grounded through #11 of IC73.Magnetic field will generate so that the second side of RY72 is activated and
230V is supplied to the compressor. On the other hands, if #37 of micro processor turns Low(0V), #8 of IC73,
the current of RY 72 relay, and magnetic field will shut down in sequence. A contact point in secondary side of
Relay 72 is off. Finally compressor will stop.
4) The principles of other loads is the same as 3) item described.
Note) SSR(Solid State Relay) is a kind of Relay.
*COMP. equivalence circuit of drive section
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