Kelvinator KM-200D User manual

Service Manual
Microwave Oven
Model:KM-200D

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  
SAFETY AND PRECAUTIONS........................................................................................................... 2
1. FOR SAFE OPERATION.............................................................................................................. 2
2. FOR SAFE SERVICE PROCEDURES ......................................................................................... 2
SPECIFICATIONS............................................................................................................................... 3
EXTERNAL VIEW................................................................................................................................ 4
1. OUTER DIMENSION..................................................................................................................... 4
2. FEATURE DIAGRAM.................................................................................................................... 5
3. CONTROL PANEL........................................................................................................................ 6
INSTALLATION................................................................................................................................... 7
OPERATIONS AND FUNCTIONS....................................................................................................... 8
DISASSEMBLY AND ASSEMBLY...................................................................................................... 9
INTERLOCK MECHANISM AND ADJUSTMENT............................................................................... 16
TROUBLE SHOOTING GUIDE ........................................................................................................... 17
MEASUREMENT AND TEST..............................................................................................................21
1. MEASUREMENT OF THE MICROWAVE POWER OUTPUT ...................................................... 21
2. MICROWAVE RADIATION TEST................................................................................................. 22
3. COMPONENT TEST PROCEDURE............................................................................................. 23
WIRING DIAGRAM.............................................................................................................................. 24
PRINTED CIRCUIT BOARD................................................................................................................ 25
1. CIRCUIT CHECK PROCEDURE .................................................................................................. 25
2. P.C.B. CIRCUIT DIAGRAM........................................................................................................... 29
3. P.C.B. LOCATION NO .................................................................................................................. 30
EXPLODED VIEW AND PARTS LIST................................................................................................. 32
1. DOOR ASSEMBLY ....................................................................................................................... 32
2. CONTROL PANEL ASSEMBLY.................................................................................................... 32
3. TOTAL ASSEMBLY....................................................................................................................... 32
(a) Do not operate or allow the oven to be operated with the door open.
(b)Make thefollowing safetychecks on allovens to be serviced before activating the magnetron or othermicrowave
source, and make repairs as necessary: (1) Interlock operation, (2) Proper door closing, (3) Sealand 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 power to the microwave oven 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 connections.
(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 verifycompliance with the Federal performance standard should be performed on
each oven prior to release to the owner.
PRECAUTIONS TO BE OBSERVED BEFORE AND
DURING SERVICING TO AVOID POSSIBLE
EXPOSURE TO EXCESSIVE MICROWAVE ENERGY


SAFETY AND PRECAUTIONS
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 personnelshould 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 gasket plate and oven cavity surface should 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 notattempt 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 priorto servicing the oven.
2)If any certified oven unitis foundto servicing, a microwave emission check should be performed prior to servicing the oven.
(a) inform the manufacturer, importer or assembler,
(b) repair the unit at no cost to the owner,
(c) attemptto ascertain the cause of the excessive leakage,
(d) tell the owner ofthe unit notto 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 notto operate the oven and contact the
manufacturer immediately.
IMPORTANT
The wire in this mains lead coloured in accordance with the following code.
Green-and-yellow : Earth
Blue : Neutral
Brown : Live
As the colours of the wires in the manins lead of this appliance may not correspond with the coloured markings
identifying the terminals in your plug, proceed as follows.
The wire which is coloured green-and-yellow mustbe connected to the termianl in the plug which is marked with the
letter ‘E’, earth symbol or coloured green-and-yellow.
The wire which is coloured blue must be connected to the terminal which is marked with the letter ‘N’ or
coloured black.
The wire which is coloured brown must be connected to the terminalwhich is marked with the letter ‘L’ or
coloured red.
This oven is designed for counter-top use only.
NOTE


SPECIFICATIONS

SPECIFICATIONS ARE SUBJECT TO CHANGE WITHOUT NOTICE.
MODEL KM-200D
POWER SUPPLY 230V-50Hz, SINGLE PHASE WITH EARTHING
POWER
CONSUMPTION
MICROWAVE1200W
GRILL
COMBINATION
MICROWAVE ENERGY OUTPUT800W
MICROWAVE FREQUENCY 2450MHz
OUTSIDEDIMENSIONS(WX HXD)465x279 x360mm(18.3x11.0x14.2in.)
CAVITYDIMENSIONS(WXHXD)290x220x306 mm(11.4x8.7 x12.0in.)
NETWEIGHTAPPROX.13Kg (28.7lbs.)
TIMER 59 min. 00 sec.
FUNCTION SELECTIONS MICROWAVE
POWER SELECTIONS 5 LEVELS
CAVITYVOLUME0.7Cu.Ft.


EXTERNAL VIEW
1. OUTER DIMENSION


EXTERNAL VIEW
2. FEATURE DIAGRAM
1.DOOR SEAL
Door seal surfaces prevent microwaves escaping from the oven cavity.
2.DOOR HOOK
When door is closed, it will automatically shutoff. If door is opened while oven is operating, magnetron tube will
immediately stop operating.
3.DOOR SCREEN
Allows viewing offood. The screen is transparent to light, but prevents microwaves escaping.
4.SPATTER SHIELD
Protects the microwave outlet from splashes ofcooking foods.
5.OVEN LAMP
Automatically turns on during oven operating.
6.SAFETY INTERLOCK SYSTEM
7.CONTROL PANEL
8.GLASS COOKING TRAY
Made ofspecial heatresistant glass.The tray can be easily removed for cleaning. Make sure it is correctly positioned
(indentation) before operating. Place food in a suitable container(dish) on the tray.
9.OVEN FRONT PLATE
10. DOOR OPENING BUTTON
To open the door,push the door opening button.
11. ROLLER GUIDE
Supports the glass cooking tray.


EXTERNAL VIEW
3. CONTROL PANEL
1. Display -
Cooking time, power level,indicators and present time are displayed.
2. Defrost -
Used to defrost foods by weight or time.
3. Power -
Used to set power level.
4. Auto cook -
Used to cook using a program orto reheat.
5. Start/Easy cook -
Used to startthe oven operation and also increase the reheat time by 30 seconds.
6. Stop/Clear -
Used to stop the oven operation or to erase allentries.
7. Clock -
Used to set clock.
8. Dial Knob -
Used to setthe time and weight.


INSTALLATION
1. Steady, flat location
This microwave oven should be set on a steady, flat surface.
This microwave oven is designed for counter top use only.
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 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, antenna or feeder and so on.
Position the oven as far from them as possible.
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 mightbe adversely
affected and breakdowns occur.
5. Power supply
 Check your local power source.
This microwave oven requires a current of approximately 6 amperes, 230 Volts, 50 Hz.
 Power supply cord is about 0.8 meters long.
 The voltage used must be the same as specified on this oven.Using a highervoltage may result in a fire or other accident
causing oven damage. Using low voltage will cause slow cooking. We are not responsible for damage resulting from use
of this oven with a voltage of ampere fuse other than those specified.
 This appliance is supplied with cable of specialtype, which,if damaged, must be repaired with cable of same type.
Such a cable can be purchased fromYapay and mustbe installed bya Qualified Person.
6. Examine the oven after unpacking for any damage such as:
A misaligned door, broken door or a dent in cavity.
If any of the above are visible, DO NOT INSTALL, and notify dealer immediately.
7. Do not operate the oven if it is colder than room temperature
(This may occur during delivery in cold weather.) Allow the oven to become room temperature before operating.
This appliance must be earthed. In the event of an electrical short circuit, earthing reduces the risk of the electric shock by
providing an escape wire for the electric current.This appliance is equipped with a cord having a earthing wire with a earthing
plug.The plug must be plugged into an outlet thatis properly installed and earthed.
WARNING
Improper use of the earthing plug can result in a risk of electric shock. Consult a qualified electrician or serviceman if
the earthing instructions are not completely understood, or if doubt exists as to whether the appliance is properly
earthed,and either : Ifit is necessary to use an extension cord, use only a 3-wire extension cord that has a 3-blade
earthing plug, and a 3-slot receptacle that will accept the plug on the appliance. The marked rating of the extension
cord should be equal to or greater than the electrical rating of the appliance, orDo not use an extension cord.
EARTHING INSTRUCTIONS

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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. When the oven door is opened, the light turns off.
5. The oven door can be opened at any time during operation by touching the door release button on the control panel.
The oven will automatically shut off. To restart the oven, close the door and then touch Start button.
6. Each time a button is touched, a BEEP will sound to acknowledge the touch.
7. The oven automatically cook on full power unless set to a lower power level.
8. The display will show “:0”when the oven is plugged in.
9. Time clock returns to the present time when the cooking time ends.
10. When the Stop/Clear button is touched during the oven operation, the oven stops cooking and all information retained.
To erase all information (except the present time), touch the Stop/Clear button once more. If the oven door is opened
during the oven operation, all information is retained.
11. If the Start button is touched and the oven does not operate, check the area between the door and door seal
for obstructions and make sure the door is closed securely.
The oven will not start cooking until the door is completely closed or the program has been reset.
Wattage output chart
The power level is set by pressing the Power button. The chart shows the display, the power level and the percentage of power.
Touch Power button Power level (Display) Approximate Percentage of Power
Once P-HI 100 %
Twice P-80 80 %
3 times P-60 60 %
4 times P-40 40 %
5 times P-20 20 %
OPERATIONS AND FUNCTIONS
Make sure the oven is properly installed and plugged into the electrical outlet.


DISASSEMBLY ANDASSEMBLY
Cautions to be observed when trouble shooting
Unlike many other appliances, the microwave oven is high-voltage, high-current equipment.
It is completely safety during normal operation. However, carelessness in servicing the oven
can resultin an electric shock or possible danger from a short circuit.
You are asked to observethe following precautions carefully.
1. Always remove the power plug from the outlet before servicing.
2. Use an insulated screwdriver and ware rubber gloves when servicing the high voltage side.
3. Discharge the high voltage capacitor before touching any oven components or wiring.
(1)Check the earthed.
Do not operate on a two-wire extension cord.
The microwave oven isdesigned to be used with earthed.
It is imperative, therefore, to makes sure it is earthed properly
before beginning repair work.
(2) Warning about the electric charge in the high voltage capacitor.
Forabout 30 seconds after the operation stopped and electric
charge remains in the high voltage capacitor. When replacing
or checking parts, shortbetween oven chassis and the negative
high terminal of the highvoltage capacitor, by using a properly
insulated screwdriver to discharge.
4. When the 12A fuse is blown out due to the operation of the monitor
switch; replace primary interlock switch, secondary interlock switch
and interlock monitor switch.
5. After repair or replacementof parts, make sure that the screws are
properly tightened, and all electrical connections are tightened.
6. Do not operate without cabinet.
CAUTION
WARNING
Service personnelshould remove their watches whenever working close to or replacing the magnetron.
When servicing the appliance,need a care of touching or replacing high potentialparts because of electricalshockor
exposing microwave. These parts are as follows - HV Transformer, Magnetron, HV Capacitor, HV Diode. HV Fuse.


DISASSEMBLY ANDASSEMBLY
1. To remove cabinet
1) Remove three screws on cabinet back.
2) Push the cabinet backward.
2. To remove door assembly
1) Remove a screw which secure the stopperhinge top.
2) Remove the door assembly from top plate ofcavity.
3) Reverse the above for reassembly.
NOTE
After replacing the door assembly, perform a check of correct alignment with the hinge and cavity frontplate.


DISASSEMBLY ANDASSEMBLY
3. To remove door parts.
(1) KM-200D
REF. NO PART CODE PART NAME DESCRIPTION QTY REMARK
A01 3512203800 FRAME DOOR ABS XR-401 H-2938 1
A02 3517003050 BARRIER-SCREEN*O ACRYL 1
A03 3515304610 SUPPORTER BARR-S*O PP 1
A04 3515204100 STOPPER HINGE *T AS KOR-63150S 1
A05 3511705500 DOOR WELD AS KOR-61150S 1
A06 3517002800 BARRIER-SCREEN *I POLYESTER T0.1 1
A07 3512300200 GASKET DOOR PP 1
A08 3513100700 HOOK POM 1
A09 3515101300 SPRING HOOK PW1 1
REF. NO PART CODE PART NAME DESCRIPTION QTY REMARK


DISASSEMBLY ANDASSEMBLY
1) Remove the gasket door from door plate.
2) Remove the barrier screen innerfrom door plate.
3) Remove the door frame from door plate.
4) Remove the stopper hinge top from door plate.
5) Remove the spring and the hook.
6) Remove the supporter barrier screen outer from doorframe.
7) Remove the barrier screen outer from doorframe.
8) Reverse the above steps for reassembly.
4. Method to reduce the gap between the door sealand the oven front surface.
1) To reduce gap located on part ‘A’.

Loosen a screw on stopper hinge top,and then
push the door to contactthe door seal to oven front surface.

Tighten a screw.
2) To reduce gap located on part ‘B’.

Loosen two screws on stopperhinge under, and then
push the door to contactthe door seal to oven front surface.

Tighten two screws.
NOTE
A small gap may be acceptable if the microwave leakage does not exceed 4mW/cm
2
.

13
DISASSEMBLY AND ASSEMBLY
5. To remove control panel parts.
(1) KM-200D
REF. NO PART CODE PART NAME DESCRIPTION Q’TY REMARK
B01 3515501500 WINDOW DISPLAY PMMA 1
B02 3516719420 CONTROL PANEL ABS XR-401 H-2938 1
B03 3516907400 BUTTON FUNCTION ABS 1
B04 3516907600 BUTTON FUNCTION ABS 1
B05 3514321400 PCB SUB AS KOR-631R0S 1
B06 3514321300 PCB MAIN AS KOR-631R0S 1
B07 7122401211 SCREW TAPPING T2S TRS 4X12 MFZN 3
B08 7621301011 SCREW TAPPING T2 PAN 3X10 PW MFZN 4
B09 3513405210 KNOB VOLUME ABS 1
B10 3516907500 BUTTON FUNCTION ABS 1
B11 3513702700 LEVER DOOR OPEN ABS 1
B12 441G430171 SPRING BUTTON SWP DIA 0.7 1
B13 3516906900 BUTTON DOOR OPEN ABS 1
REF. NO PART CODE PART NAME DESCRIPTION Q’TY REMARK


DISASSEMBLY ANDASSEMBLY
1)Remove the screw which secure the control panel,push up two snap fits and draw forward the control panelassembly.
2) Remove the door open lever from the control panel.
3) Remove four screws which secure the PCB assembly to control panel.
4) Disconnectmembrane tail from the connector of the PCB assembly.
5) Detach membrane from the control panel.
6) Remove door open button and button spring from the control panel.
7) Reverse the above steps for reassembly.
6. To remove high voltage capacitor.
1) Remove a screw which secure the grounding ring terminal
of the H.V.diode and the capacitorholder.
2) Remove the H.V. diode from the capacitor holder.
3) Reverse the above steps for reassembly.

High voltage circuitwiring
7. To remove magnetron.
1) Remove a screw which secure the magnetron.
2) Remove the magnetron.
3) Reverse the above steps for reassembly.
NOTE
Never install the magnetron without the metallic gasket plate which is packed with each magnetron to prevent
microwave leakage.Wheneverrepair work is carried out on magnetron,check the microwave leakage.It shall
not exceed 4mW/cm
2
for a fully assembled oven with door normally closed.


DISASSEMBLY ANDASSEMBLY
8. To remove wind guide assembly.
1) Remove a screw for earthing.
2) Remove the noise filter from the wind guide.
3) Remove a screw which secure the wind guide assembly.
4) Draw forward the wind guide assembly.
5) Pull the fan from the motor shaft.
6) Remove two screws which secure the motor shaded pole.
7) Remove the motor shaded pole.
8) Reverse the above steps for reassembly.
9. To remove H.V.transformer.
1) Remove four screws holding the H.V.transformer.
2) Remove the H.V.transformer.
3) Reverse the above steps for reassembly.


INTERLOCK MECHANISM AND ADJUSTMENT
The doorlockmechanism is a device which has been specially designed to completely eliminate microwave radiation when
the door is opened during operation, and thus to perfectly prevent the danger resulting from the leakage of microwave.
(1) Primary interlock switch
When the door is closed, the hook locks the oven door. If the door is not closed properly, the oven will not operate.
When the door is closed,the hook pushes the button of the microswitch. Then the button of the primary interlock switch
bring it under ON condition.
(2) Secondary interlock switch and interlock monitor switch
When the door is closed,the hook pushes the lock lever downward. The lock leverpresses the button of the interlock
monitor switch to bring it under NO condition and presses the button of the secondary interlock switch to bring it under
ON condition.
(3) Adjustment steps
a) Loosen the one mounting screw.
b) Adjust interlock switch assembly position.
c) Make sure that lock lever moves smoothly after adjustment is completed.
d) Tighten completely one mounting screw.
ADJUSTMENT
Interlock monitor switch
When the door is closed,the interlock monitor switch should be changed(NO condition) before other switches are closed.
When the door is opened, the interlock monitor switch should be changed(NC condition) after other switches are opened.
NOTE
Microwave emission test should be performed after adjusting interlock mechanism. If the microwave emission exceed
4mW/cm
2
, readjust interlock mechanism.


TROUBLE SHOOTING GUIDE
Following the procedure below to check if the oven is defective or not.
1)Check earthing before trouble checking.
2)Be careful of the high voltage circuit.
3)Discharge the high voltage capacitor.
4)When checking the continuity ofthe switches, fuse orhigh voltage transformer, disconnectone lead wire from these parts
and check continuity with the AC plug removed. To do otherwise may result in a false reading or damage to your meter.
(TROUBLE 1)
Oven does not operate at all: any inputs can not be accepted.
NOTE
When electric parts are checked, be sure the power cord is not inserted the wall outlet.
Check wire harness, wiring and connected of the terminals and power cord before check the parts listed below.
CHECK RESULT CAUSE REMEDY
Fuse blows. Continuity
No Continuity
Continuity
0 infinite
Ω
or
Approx.
150~310
(normal)
Replace
NOTE 1
Replace
NOTE 1
Replace
Replace
Check continuity of
primary winding of low
voltage transformer
Malfunction
of interlock
monitor
switch
Defective low
voltage
transformer
Check continuity of
interlock monitor switch
with door closed
(COM NC)

Check continuity ofprimary
interlock switch contact
with door partially open
until interlock monitor switch
contact close
(COM<->NO)
Shorted contacts
of primary
interlock switch.
Fuse again
blows
Disconnect high voltage
fuse and operate the unit Defective high
voltage transformer
CONDITION
No Continuity Replace
NOTE 1
Check continuity ofboth
primary and secondary
interlock switch with door
colosed
Malfunction of
interlock switch
No Continuity
Continuity


TROUBLE SHOOTING GUIDE
( TROUBLE 2 )
Display shows all figures selected, but oven doesnotstart cooking, even though desired program and time
are setand start pad is tapped.
CONDITION CHECK RESULT CAUSE REMEDY
Outlet has
proper voltage
Fuse does not
blow.
Check continuity of
magnetron No
Continuity Defective magnetron Replace
No
Continuity
Normal Defective touch
control circuit
Open power
supply cord Replace
Check continuity of
power supply cord
Adjust
Check continuity of
noise filter board No
Continuity Defective line
filter board Replace
NOTE
All these switches mustbe replaced at the same time, please refer to “Interlock Mechanism And Adjustment”.
CONDITION CHECK RESULT CAUSE REMEDY
Turn table
motor and
oven lamp do
not turn on
No
Continuity Adjustor
replace
Adjustor
replace
Replace
Replace
Malfunction
of primary
interlock
switch
No
Continuity
0 V
Approx.
15 VDC
Check continuity of
primary interlock switch
Check continuity of
secondary interlock and
D.O.M. switches
Check D.C. voltage
being supplied to
RELAY (RY2) coil
Malfunction
of secondary
interlock and
D.O.M. switch
Defective
touch control
circuit
Faulty
contacts of
RELAY
(RY2) or open
relay coil


TROUBLE SHOOTING GUIDE
(
TROUBLE 3 )
No microwave oscillation even though fan motor rotates.
CONDITION CHECK RESULT
Continuity
Continuity in
backward
direction
0Ω
or

No
Continuity
No
Continuity
0 V
Approx
15 VDC
CAUSE
Defective
high voltage
transformer
Defective
high voltage
rectifier
Defective
magnetron
Defective
magnetron
Defective
high voltage
transformer
Defective
high voltage
transformer
Defective
touch control
circuit
Faulty
contacts or
RELAY
(RY1) or open
relay coil
REMEDY
Replace
Replace
Replace
Replace
Replace
Replace
Replace
Replace
No microwave
oscillation
Check continuity of high
voltage rectifier in
forward and backward
direction with DC
megger
Check continuity of high
voltage capacitor
terminals with wires
removed
Connect megger leads to
magnetron terminal and
magnetron body
Check resistance of
primary and secondary
coil of high voltage
transformer
Check continuity of
magnetron with wires
removed
Check continuity of
filament terminal of high
voltage transformer
Check D.C. voltage
being supplied to
RELAY (RY1) coil
Continuity
Check continuity of high
voltage fuse
No Continuity
Replace high voltage fuse