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Power circuit is composed of switching mode power supply (SMPS) electric parts. SMPS is composed of rectifying part
(D1~D4, CE1) which converts AC to DC voltage, switching part (IC2) which switches this converted DC voltage, trans which
transmits primary energy to secondary energy, secondary power source which transmits power to MICOM and IC, and feed
back part (IC3, ZD1) which feeds back voltage to primary trans in order to maintain constant secondary voltage. 
The voltages at each part are as follows.

Note : If circuit is abnormal, repair it after 3 minutes when power cord is unplugged. Be care of electric shock as high

voltage (DC 310 V) is applied to the circuit.

In the trans secondary side is composed of power source (12 Vdc) for driving relay and power source (5 Vdc) which supplies
power to MICOM and IC. Voltages in each part are as follows.

This is to generate basic time for synchronous clock and time calculation for
internal logic element to send and receive information.Standard parts should be
used as the time calculated by IC1 shall be changed or shall not work if OSC1
specification is changed.

Reset circuit is to initialize RAM in MICOM (IC1) and make all functions
to start  from the initial conditions when  power is nitially applied or
power is reapplied to MICOM after power cut. Low voltage is applied for
10 ms to the reset terminal of MICOM when power is applied. 5 voltage
is applied to the reset terminal for general operation. (MICOM does not 

work when IC9(Reset IC) is failed)

- 31 -

Position

VA1

CM1

CM2

CE2

CE4

Voltage

220 Vac

14 Vac

17 Vac

12 Vdc

5 Vdc

* Freezer fan motor shall stop when freezer or refrigerator door is open. Freezer fan  motor shall immediately operate when

freezer or refrigerator door is closed.

* Door switches A, B, C, D, E, F of freezer and refrigerator are connected to the door opening detecting circuit in Micom.

* Home bar door switch E, F is parallelly connected to the refrigerator door switch C, D. Therefore it can detect door opening

when one of the door is open. 

- 32 -

Refrigerator

Machine

Defrost

AC Converting

Heater, Plate

Fan Motor

Load Types

Room

Heater

Relay

(W/TANK)

High

Standard

Speed

Speed

Measuring Locations(IC 6)

No.10

No.11

No.12

No.16

No.13

No.14

Condition

ON

Below 1 V

OFF

12 V

* Freezer fan motor shall operate when freezer, refrigerator, or home bar door is open.

* Door switches A, B, C, D of freezer and refrigerator are connected to door opening detecting circuit in Micom.

* Home bar door switch E, F is parallelly connected to the refrigerator switch C, D. Therefore it can detect door opening

when one of the door is open. 

- 33 -

Refrigerator

Machine

Defrost

AC Converting Refrigerator

Home Bar

Fan Motor

Load Types

Room

Heater

Relay

Compartment Lamp

Heater

High

Standard

Speed

Speed

Measuring Points(IC 4)

No.10

No.11

No.12

No.16

No.15

No.13

No.14

Conditions

ON

Below 1 V

OFF

12 V

-8
1-

Food Odor.

Food (garlic, kimchi, etc)

- Check the food is not wrapped.

- Dry deodorizer in the shiny and 

- Check the shelves or inner 

windy place.

wall are stained with food juice.

- Store the food in the closed

- Check the food in the vinyl wraps.

container instead of vinyl wraps.

- Chedk food cleanliness.

- Clean the refrigerator and set 

button at "strong".

Plastic Odor.

Odors of mixed food and plastic 

- Check wet food is wrapped with 

- Clean the refrigerator.

odors.

plastic bowl and bag.

- Persuade customers not to use

- It happens in the new refrigerator.

plastic bag or wraps with wet food

or odorous foods.

Odor from the

Odor from the old deodorizer.

- Check the deodorizer odors.

- Dry the deodorizer with dryer and 

*Deodorizer : option

deodorizer.

then in the shiny and windy place.

- Remove and replace the 

deodorants.