Daewoo KOR-6185 User manual

Service Manual
Microwave Oven
Model: KOR-6185
DAEWOO ELECTRONICS CO., LTD.

2
PRECAUTIONS TO BE OBSERVED BEFORE AND
DURING SERVICING TO AVOID POSSIBLE EXPOSURE
TO EXCESSIVE MICROWAVE ENERGY
(a) Do not operate or allow the oven to be operated with the door open.
(b) Make the following safety checks on all ovens to be serviced before activating the magnetron or
other microwave source, and make repairs as necessary: (1) Interlock operation, (2) proper door
closing, (3) seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or
loosening of hinges and latches, (5) evidence of dropping or abuse.
(c) Before turning on microwave power for any service test or inspection within the microwave
generating compartments, check the magnetron, wave guide or transmission line, and cavity for
proper alignment, integrity, and connection.
(d) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave
generation and transmission systems shall be repaired, replaced, or adjusted by procedures
described in this manual before the oven is released to the owner.
(e) A microwave leakage check to verify compliance with the Federal Performance Standard should
be performed on each oven prior to release to the owner.
TABLE OF CONTENTS
PROPER USE AND SERVICE PRECAUTIONS......................................3
SPECIFICATIONS.................................................4
FEATURE DIAGRAM.............................................5
INSTALLATION...........................................................6
OPERATION.........................................................................7
MEASUREMENT OF THE MICROWAVE OUTPUT POWER...................................................8
MICROWAVE RADIATION TEST......................................................................................................9
WIRING DIAGRAM......................................................................................................................................................10
CIRCUIT DESCRIPTION............................................................................................................................................12
PRECAUTIONS FOR DISASSEMBLY AND REPAIR................................................................................................14
DISASSEMBLY AND ASSEMBLY.............................................................................................................................15
INTERLOCK MECHANISM.........................................................................................................................................20
TROUBLE SHOOTING GUIDE..................................................................................................................................22
COMPONENT TEST PORCEDURE...........................................................................................................................24
EXPLODED AND PARTS LIST..................................................................................................................................26

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CAUTION : This Device is to be Serviced Only by Porperly Qualified Service Personnel. Consult the Service
Manual for Proper Service Procedures to Assure Continued Compliance with the Federal
Performance Standard for Microwave Ovens and for Precautions to be Taken to Avoid Possible
Exposure to Excessive Microwave Energy.
CAUTION
MICROWAVE RADIATION
PERSONNEL SHOULD NOT BE EXPOSED TO THE MICROWAVE ENERGY WHICH MAY RADIATE
FROM THE MAGNETRON OR OTHER MICROWAVE GENERATING DEVICE IF IT IS IMPROPERLY
USED OR CONNECTED. ALL INPUT AND OUTPUT MICROWAVE CONNECTIONS, WAVEGUIDES,
FLANGES, AND GASKETS MUST BE SECURE. NEVER OPERATE THE DEVICE WITHOUT A
MICROWAVE ENERGY ABSORBING LOAD ATTACHED. NEVER LOOK INTO AN OPEN WAVEGUIDE
OR ANTENNA WHILE THE DEVICE IS ENERGIZED.
1. FOR SAFE OPERATION
Damage that allows the microwave energy (that cooks or heats the food) to escape will result in poor cooking and
may cause serious bodily injury to the operator.
IF ANY OF THE FOLLOWING CONDITIONS EXIST, OPERATOR MUST NOT USE THE APPLIANCE.
(Only a trained service personnel should make repairs.)
1) A broken door hinge.
2) A broken door viewing screen.
3) A broken front panel, oven cavity.
4) A loosened door lock.
5) A broken door lock.
The door seal area and oven cavity surface be kept clean.
No grease, soil or spatter should be allowed to build up on these surfaces or inside the oven.
DO NOT ATTEMPT TO OPERATE THIS APPLIANCE WITH THE DOOR OPEN. The microwave oven has
concealed switches to make sure the power is turned off when the door is opened. Do not attempt to defeat them.
DO NOT ATTEMPT TO SERVICE THIS APPLIANCE UNTIL YOU HAVE READ THIS SERVICE MANUAL.
2. FOR SAFE SERVICE PROCEDURES.
1) If the oven is operative prior to servicing, a microwave emission check should be performed prior to servicing
the oven.
2) If any ascertained oven unit is found to have excessive emission level 5mW/cm
2
, the service person should:
(a) inform the manufacturer, importer or assembler,
(b) repair the unit at no cost to the owner,
(c) attempt to ascertain the cause of the excessive leakage,
(d) tell the owner of the unit not to use the unit until the oven has been brought into compliance.
3) If the oven operates with the door open, the service person should tell the user not to operate the oven and
contact the manufacturer immediately.
PROPER USE AND SERVICE PRECAUTIONS

4
ITEM SPECIFICATION
POWER SUPPLY 120V~60HZ, SINGLE PHASE WITH EARTHING
POWER CONSUMPTION 920W
MICRO WAVE OUTPUT POWER 600W (IEC 705)(FULL MICROWAVE POWER)
FREQUENCY 2450 MHz
OUTSIDE DIMENSIONS (WXHXD) 465 X 274 X 364 mm
CAVITY DIMENSIONS(WXHXD) 290 X 200 X 290 mm
NET WEIGHT APPROX 12.5Kg
TIMER 35 min. DUAL SPEED
POWER SELECTIONS 5 LEVELS
CAVITY VOLUME 0.6 Cu. Ft.
SPECIFICATIONS
274
465 364
0
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25
30
35
*Specifications are subject to change without notice.

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1Saftey Interlock System.
2Door Viewing Screen - Allows viewing of food, the screen is designed so that light can
pass through, but not the microwave.
3Door Hook - When the door is closed, it will automatically shut. If the door is opened
while the oven is operating, the magnetron will immediately stop operating.
4Oven Cavity
5Door Seal - Door seal maintains the microwave energy within the oven cavity and
prevents micro leakage.
6Glass Cooking Tray - Made of special heat resistant glass. Food in a proper receptacle
is placed on this tray for cooking.
7Roller guide - This must always be used for cooking together with the glass cooking tray.
8Coupler - this fits over the shaft in the center of the oven’s cavity floor. This is to remain
in the oven for all cooking.
9Knob V.P.C - Used to select a microwave power level.
0Knob timer - Used in setting cooking time for all functions.
qDoor Release button - By pushing this button the latch system cut of all circuits and
stops the oven before the door is opend.
FEATURES DIAGRAM
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5
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9
264
7
10
11
8
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INSTALLATION
1
Steady, flat location
This microwave oven should be set on a steady, flat surface.
2
Leave space behind and side
All air vents should be kept a clearance. If all vents are covered during operation, the oven may overheat and,
eventually, cause oven failure.
3
Away from radio, and TV sets
Poor television reception and radio interference may result if the oven is located close to a TV, Radio or antenna,
feeder and so on.
4
Away from heating appliances and water taps
Keep the oven away from hot air, steam or splash when choosing a place to position it, or the insulation might be
adversely affected and breakdowns occur.
5
Power supply
• Check your local power source.
This microwave oven requires a current of approximately 6 amperes, 120 Volts, 60Hz grounded outlet.
• Power supply cord is about 1.0 meters long.
1. A short power-supply cord is poovided to reduce the risks resulting from becoming entangled in or tripping over a
longer cord.
2. Longer cord sets or extension cords are available and may be used if care is exercised in their use.
3. If a long cord or extension cord is used, (1) the marked electrical rating of the cord set or extension cord should be at
least as great as the electrical rating of the appliance, (2) the extension cord must be a grounding-type 3-wire cord,
and (3) the longer cord should be arranged so that will not drape over the countertop or tabletop where it can be
pulled on by children or tripped over unintentionally.
6
Examine the oven after unpacking for any damage such as:
A misaligned door, Broken door, A dents in cavity.
If any of the above are visible, DO NOTINSTALL, and notify dealer immediately.
When use 3-pronged plug
3-prong Receptacle
Receptacle
Box cover
3-prong plug
When use a grounding adaptor, make
usre the receptacle box is fully
grounded
Grounding Lead
Receptacle Box cover
Grounding Adaptor
Receptacle

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OPERATION
1
Connect the main lead to an electrical outlet.
2
After placing the food in a suitable container, open the oven door and put it on the glass tray.
The glass tray must always be in place during cooking.
3
CLOSE THE DOOR securely.
4
Choose cooking power level by setting V.P.C.
knob to the desired position.
Refer to cookbook for recommended power
levles.
5
Determine cooking time. Consult cookbook for
recipe timing.
• Oven light turns on and cooling fan starts to
operate. Microwave cooking starts.
6
You may open the door while the oven is
operating. As soon as the door is opened, the
safety mechanisms stop the generation of
microwave power and the operation of cooking
timer.
If you wish to change the time during cooking,
simply adjust the Timer to the desired time.
7
When the timer reaches zero, a bell will ring
and the unit will turn off.
• Oven light turns off.
If additional cooking time is needed and the
door is closed, the oven will automatically start
when the Timer is reset.
NOTE :
1. When setting Timer for less than 2 minutes, turn the
Timer past 2 minutes and then return to the correct
timer setting.
2. Various clicking noises may be heard when turning
the V.P.C. Knob. This is normal and does not affect
the operation of your microwave oven.
Variable power cooking
ON and OFF cycle time of mechanicial V.P.C. switch is 30 seconds.
When the V.P.C. knob is set to the desired position and timer knob turns to the desired position, the V.P.C
switch has a cycle (ON/OFF time (sec)) listed below.
012
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Variable power setting ON/OFF time (SEC) POWER
(HIGH) 30/0 100%
(MED HIGH) 23.2/6.8 77%
(MEDIUM) 16.5/13.5 55%
(DEFROST) 9.8/20.2 33%
(WARM) 5/25 17%

8
MEASUREMENT OF THE MICROWAVE OUTPUT POWER
Microwave output power can be checked by indirectly measuring the temperature rise of a certain amount of water
exposed to the microwave as directed below.
Procedure
1. Microwave power output measurement is made with the microwave oven supplied at rated voltage and operated at
its maximum microwave power setting with a load of 1,000±5cc of potable water.
2. The water is contained in a cylindrical borosilicate glass vessel having a maximum material thickness of 3 mm and
an outside diameter of approximately 190 mm.
3. The oven and the empty vessel are at ambient temperature prior to the start of the test.
The initial temperature of the water is 10±2˚C(50±3.6˚F).
It is measured immediately before the water is added to the vessel. After addition of the water to the vessel, the
load is immediately placed on the center of the shelf which is in the lowest normal position.
4. Microwave power is switched on.
5. Heating time should be exactly 70 seconds.
Heating time is measured while the microwave generator is
operating at full power.
The filament heat-up time for magnetrons is not included.
6. The initial and final water temperatures are selected so that
the maximum defference between the ambient and final water
temperature is 5K.
7. The microwave power output P in watts is calculated from the following formula:
• ∆ T is actual temperature rise.
• t is the heating time.
The power measured should be 600W±10%.
CAUTION :
1. Water load should be measured exactly to 1 liters.
2. Input power voltage should be exactly 220 volts as specified.
3. Ambient temperature should be 20±2˚C (68±3.6˚F)
Water Load
Tray
P = 4187 X ∆T/t

9
MICROWAVE RADIATION TEST
WARNING
• Make sure to check the microwave leakage before and after repair or adjustment.
• Always, start measuring of an unknown field to assure safety for operating personnel from microwave energy.
• Do not place your hands into any suspected microwave radiation field unless the safe density level is known.
• Care should be takent not to place the eyes in direct line with the source of microwave energy.
• Slowlyapproach the unit under test until the radiometer reads an appreaciable microwave leakage from the unit
under the test.
PROCEDURE
A) Prepare Microwave Energy Survey Meter, 600cc glass beaker, glass thermometer 100˚C or 212˚F.
B) Pour 275cc±15cc of tap water initially at 20±5˚C(68±9˚F) in the 600cc beaker with an inside diameter of approx.
9.5cm (3.5 in).
C) Place it at the center of the tray and set it in a cavity.
D) Close the door and operate the oven.
E) Measure the leakage by using microwave energy survery meter with dual ranges, set to 2450 MHz.
- Measured radiation leakage must not exceed the values prescribed below.
• Leakage for a fully assembled oven with door normally closed must be less than 4mW/cm
2
.
- When measuring the leakage, always use the 2 in (5cm) space cone with probe. Hold the probe perpendicular to
the cabinet, door. Place the space cone of the probe on the door, cabinet, door seam, door viewing screen, the
exhaust air vents and the suction air vents.
- Measuring should be in a counter-clockwise direction at a rate of 1 inch/sec. If the leakage of the cabinet door
seam is unkow, move the prove more slowly.
- When measuring near a corner of the door, keep the probe perpendicular to the areas making sure the probe end
at the base of the cone does not get closer than 2 inches from any metal.
If it does, erroneous reading may result.
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KOR-6185 WIRING DIAGRAM
NOTE RD : RED WH : WHITE BK : BLACK GN : GREEN BR : BROWN
OR : ORANGE BL : BLUE GY : GRAY GE : GREEN/YELLOW
CL : CAVITY LAMP FM : FAN(BLOWER) MOTOR TM : TIMER MOTOR V.P.C : VARIABLE POWER CONTROLLER GM : GEAR MOTOR I.W : INTERNAL WIRING
[CONDITION] DOOR : OPEN TIMER : ON V.P.C : HIGH
TM FM GM CL
3 2 1
1
2
M
3
TIMER ASSY
POWER OUTLET SOCKET
GN
WH
RD
TIMER SWITCH V.P.C
GY GY
GY
GY
RD
I.W
I.W
I.W
BL OR
BK
PRIMARY INTERLOCK SWITCH
RD
HIGH VOLTAGE TRANSFORMER
H.V. CAPACITOR
H.V. DIODE
MAGNETRON
INTERLOCK MONITOR S/W
BK
BK
BK
WH
NO NC
COM
WH
WH
SELECTOR SWITCH
SECONDARY INTERLOCK SWITCH
RD
FUSE
BR(BK)
BL(WH)
GE(GN)
POWER SUPPLY SINGLE PHASE ONLY