Kenmore 60282, 721.60289000, 721.60282000 Service Manual

DIVISION 20

BASIC FIELD MANUAL

FOR

MICROWAVE OVEN

MODEL 721.60282000

721.60289000

MODEL 721.60282000

721.60289000

March, 2000

CAUTION

WARNING TO SERVICE TECHNICIANS

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 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 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.

• Proper operation of the microwave ovens requires that the magnetron be assembled to the wave guide and cavity. Never operate the magnetron unless it is properly installed.

• Be sure that the magnetron gasket is properly installed around the dome of the tube whenever installing the magnetron.

• Routine service safety procedures should be exercised at all times.

• Untrained personnel should not attempt service without a thorough review of the test procedures and safety information contained in this manual.

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FOREWORD

Read this Manual carefully. Failure to adhere to or observe the information in this Manual may result in exposing yourself to the Microwave Energy normally contained within the oven cavity.

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MECHANICAL SERVICE INFORMATION

TABLE OF CONTENTS

1. Adjustment Procedures....................................................................................................................................... 3

2. Precautions on Installation .................................................................................................................................. 5

3. General Precautions in Use................................................................................................................................. 5

4. Trial Operation..................................................................................................................................................... 5

5. Specifications ...................................................................................................................................................... 6

6. Overall Circuit Diagram ....................................................................................................................................... 7-8

7. Operating Procedures ......................................................................................................................................... 9-11

8. Procedure for Measuring Microwave Energy Leakage........................................................................................ 12-13

9. Disassembly Instructions..................................................................................................................................... 14-18

10. Interlock Continuity Test.................................................................................................................................... 19

11. Test and Checkout Procedures, and Troubleshooting

A. Test Procedures............................................................................................................................................. 20-22

B. Checkout Procedures..................................................................................................................................... 23-25

C. Troubleshooting............................................................................................................................................. 26-30

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1. ADJUSTMENT PROCEDURES

To avoid possible exposure to microwave energy leakage, adjust the door latches and interlock switches, using the following procedure.

ONLY AUTHORIZED SERVICE PERSONNEL SHOULD MAKE THIS ADJUSTMENT.

The Interlock Monitor and Primary Interlock Switch acts as the final safety switch protecting the user from microwave energy. The terminals between “COM” and “NC” of the Interlock Monitor must close when the door is opened. After adjusting the Interlock Monitor Switch, make sure that it is correctly connected. See Figures 1-a and 1-b throughout this procedure.

CHECK THE DOOR LATCH AND SWITCH CLOSING.

NOTE: The outer cover of the microwave oven is

removed.

(1) Set the microwave oven on its side so that you can see

the latch board and the switches, as shown in Figure 1-a.

(2) Close the door tightly and check gaps A and B to be

sure they are no more than 1/64” (0.5 mm). See Figure

1-b for close-up view of gaps A and B (door latches). If all gaps are less than 1/64” (0.5 mm), adjustment of the latch board may not be necessary. Go to Steps 5 and 6 to check the sequence of the switches.

NOTE: To correct sequence of the Primary Interlock

Switch, Secondary Interlock Switch and the Interlock Monitor Switch is very important.

If any gap is larger than 1/64” (0.5 mm), you will need to adjust the latch board-U, L. Go to step 3 and follow all steps in order.

ADJUST THE LATCH AND SWITCH CLOSING

(3) Loosen the two screws holding the plastic latch board as

shown.

(4) With the oven door closed tightly, move the latch board

upward toward the top of the oven and/or away from the door latch until the gaps are less than 1/64” (0.5 mm).

Hold the latch board tightly in this position until you check the sequence of the switches in steps 5 and 6.

TEST THE LATCH AND SWITCH SEQUENCE

(5) Open the oven door slowly. Watch the door latch, the

Primary Switch. Release Rod and Lever on the switches to make sure they are zero to the body of the switches in the following sequence:

- Primary Interlock Switch

- Secondary Interlock Switch

- Interlock Monitor Switch

Adjust the latch board until the switches operate in this sequence. See Steps 3 and 4.

(6) Close the oven door slowly and be sure it is tightly

closed. Watch the three switches to make sure they are zero to the body of the switches in the following sequence:

- Interlock Monitor Switch

- Primary Interlock Switch

- Secondary Interlock Switch

NOTE: The Interlock Monitor Switch is an added safety

check on the Primary and Secondary Interlock Switches. If the Primary and Secondary Interlock Switches allow the oven to operate with the door open, the Monitor Switch will blow the fuse.

(7) When you achieve the proper sequence of switches in

Steps 5 and 6, tighten the latch board screws at that point.

TEST THE MICROWAVE ENERGY LEAKAGE

(8) Using a survey meter, make sure the microwave energy

is below 5 mW/cm.sq.

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MODEL 721.60282000

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LATCH BOARD

Figure 1-a

Figure 1-b

DOOR LATCH

SECONDARY INTERLOCK SWITCH

MONITOR INTERLOCK SWITCH

PRIMARY INTERLOCK SWITCH

0-1/64"

LATCH BOARD

LATCH

0-1/64"

2. PRECAUTIONS ON INSTALLATION

(Figure 2)

A. Plug the power supply cord into a 120 V AC, 60 Hz,

single-phase power source with a capacity of at least 20 amperes.

B. Since the unit weights about 38 lbs, be sure to place it

on a sturdy and flat surface.

C. Avoid placing the unit in a location where there is direct

heat or splashing water.

D. Place the unit as far away as possible from TV, radio,

etc. to prevent interference.

CAUTION

3. GENERAL PRECAUTIONS IN USE

A. Never operate the unit when it is empty. Operating the

oven with no load may shorten the life of the magnetron. Whenever cooking dry foods (dried fish, bread, etc.) or a small amount of food, be sure to put a glass of water into the cooking compartment. The turntable tray may become hot after operating, be careful when touching it.

B. Aluminum foil should be avoided because it will disrupt

cooking and may cause arcing. However, small pieces may be used to cover some parts of food to slow the cooking. Any aluminum foil used should never be closer than 2.5 cm to any side wall of the oven.

4. TRIAL OPERATION

After installation, the following sequences and results should be checked carefully. A. Put a container filled with water (about 1 liter) into the

oven, and close the door tightly. B. Touch the STOP/CLEAR and the COOK TIME keys. C. Set cooking time for 10 minutes by touching “1”

and then “0” three times. “1000” appears in the

display window. D. Touch the START key.

Make sure the cavity light comes on. The unit will begin

cooking and the display window will show the time

counting down by seconds. E. After about 5 minutes, make sure the primary interlock

switch, the secondary interlock switch and the interlock

monitor and oven lamp switch operate properly by

opening and closing the door several times. Touch the

START key each time the door is closed. F. Continue operating the unit. Four long beep sound

signal is heard when the time is up. The unit will shut off

automatically. G. Confirm the water is hot. H. Finally, measure the output power according to

“POWER OUTPUT MEASUREMENT” on page 13.

5. FEATURES AND SPECIFICATIONS

A. The safety systems incorporated in this model are:

(1) Primary interlock switch

(2) Secondary interlock switch

(3) Interlock monitor switch

(4) Choke system

(5) Magnetron thermostat

(6) Oven cavity thermostat

(Note: This thermostat located on the oven cavity will open and stop the unit from operation only if a high temperature is reached, such as, a fire created by overcooking food.)

B. Any one of 10 power output levels ranging 100W to

1000W can be selected by the touch control and

electronic computer system. C. Cooking time can be displayed on the digital readout. D. Three different cooking stages can be set. The oven

remembers three cooking stages and changes from one

cooking stage to another. This is made possible with the

memory function of the microprocessor.

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This unit is equipped with a 3-prong plug for your safety. If the wall outlet is a grounded 3-hole type, the unit will be grounded automatically.

Three-Pronged(Grounding) Plug

Figure 2

Properly Polarized and Grounded Outlet

SPECIFICATIONS

Rated Power Consumption..........................................1530W maximum

Output

..........................................................................1100W maximum (

IEC 705 Rating standard)

...................................................................Adjustable 100W through 1100W, 11 steps

Frequency....................................................................2,450 MHz ± 50 MHz

Power Supply...............................................................120V ±12V AC, 60Hz

Rated Current...............................................................13.3 Amp.

Magnetron Cooling.......................................................Forced Air Cooling

Microwave Stirring........................................................Turntable

Rectification..................................................................Rectification Voltage Doubler Half-Wave

Door Sealing ................................................................Choke System

Safety Devices.............................................................Thermostat:

Open at 90°C ± 5°C

Open at 75°C ± 5°C Fuse(20A) Primary Interlock Switch Secondary Interlock Switch Interlock Monitor

Magnetron....................................................................2M246

High Voltage Capacitor................................................Capacitor: 1.00µF, 2.1KV Ac

High Voltage Diode......................................................350mA, 9.0KV

Cavity Lamp.................................................................125V, 20W

Timer............................................................................Digital, up to 99 mm. 99 sec. (in each cooking stage)

Tray..............................................................................Tempered Safety Glass

Overall Dimensions......................................................20

/8”(W) x 123/8”(H) x 151/2”(D)

Oven Cavity Size..........................................................13

/4”(W) x 93/8”(H) x 143/8”(D)

Effective Capacity of Oven Cavity................................1.1 Cu.ft.

Accessories..................................................................Use and Care Manual ,Turntable,

Rotating Ring Assembly.

SWITCH CHART

NOTE: Use the above switch chart with circuit diagram on page 7.

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PRIMARY SECONDARY INTERLOCK INTERLOCK INTERLOCK MONITOR SWITCH SWITCH SWITCH

COM COM COM

NO NO NC

SWITCH MODE

CONDITIONS

DOOR OPEN

DOOR CLOSED

∞∞∞0

6. OVERALL CIRCUIT DIAGRAM A. SCHEMATIC DIAGRAM

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IMPORTANT SAFETY NOTE: THE SHADED AREAS ON THIS SCHEMATIC DIAGRAM INCORPORATE SPECIAL FEATURES

IMPORTANT FOR PROTECTION FROM MICROWAVE RADIATION, FIRE, ELECTRICAL SHOCK, AND

HAZARDS. WHEN SERVICING IT IS ESSENTIAL THAT ONLY MANUFACTURER’S SPECIFIED PARTS

BE USED FOR THE CRITICAL COMPONENTS IN THE SHADED AREAS OF THE SCHEMATIC DIAGRAM.

NOTICE: SINCE THIS IS BASIC SCHEMATIC DIAGRAM, THE VALUES OF COMPONENTS AND

SOME PARTIAL CONNECTIONS ARE SUBJECT TO CHANGE FOR IMPROVEMENT.

1 2 3 4 5 6 7 8

TTM

12345678

SYMBOL

NOTE:

1. DOOR IS OPEN.

2.RS: SENSING ELEMENT RC: COMPENSATING ELEMENT

3. WIRE COLOR.

COLOR WHITE BLACK

YELLOW PINK

BLUE

GREEN BROWN

YL PK

RED

GN BN

CONTROL MODULE

(8 PIN)

CONNECTOR

H.V.DIODE

H.V. CAPACITOR

BL WH GN

RDWH

BN(NC)(C)

CN4

TURNTABLE

MOTOR

SECONDARY

INTERLOCK

SWITCH

WH RD

RC RS

HUMIDITY

SENSOR

RELAY 1

RELAY 2

L.V. TRANSFORMER

(CN1)

FUSE

20A

PRIMARY INTERLOCK SWITCH (NO)

MONITOR SWITCH

H.V.TRANSFORMER

FAN

MOTOR

OVEN LAMP

MGT/OVEN

THERMOSTAT

AC 120V/60Hz SINGLE PHASE ONLY

MAGNETRON

321

B. MATRIX CIRCUIT FOR TOUCH KEY BOARD

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Figure 4

7. OPERATING PROCEDURES A. OVEN CONTROL PANEL

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Clock

Used in setting Time of Day.

Starts the oven.

Start

Display Window- Shows:

* Time of day. * Cooking time. * Cooking power level. It also function as a countdown timer when cooking.

Quick Touch Sensor

Used to set cooking time quickly and directly.

NOTE: A "beep" sounds when you touch a "key" on the control panel, to indicate that you have entered a setting.

Numbers-

Used to enter the: * Time of day. * Cooking time. * Cooking power. * Food weight for defrost.

Used in setting Auto Defrost.

Auto Defrost

Used to set cooking time.

Cook Time

Stop/Clear

Stops the oven and clears all entries except CLOCK. Once cooking has begun, however, CLEAR will function only after STOP has been touched.

Option

Kitchen Timer

You can use your microwave oven as a timer.

Add Minute

Power

Used select cooking power level.

Express Defrost

Figure 5

B. PANEL INSTRUCTIONS

The entire operation is done by simple touch control pads. (1) DISPLAY WINDOW.

The Display includes a clock and indicators that tell you time of day, cooking time settings, and cooking functions selected.

(2) QUICK TOUCH SENSOR Key

The oven's sensor will tell the oven how long to cook depending on quantity of the food in the oven.

(3) AUTO DEFROST Key

Touch this pad to thaw meat, fish, or poultry by entering a weight.

(4) NUMBER PADS

Touch Number Pads to enter cooking time, power level, quantities, or weights.

(5) COOK TIME Key

Touch this pad to set a cooking time.

(6) OPTION Key

Touch this pad to change the oven's default settings for sound, clock, scroll speed, Lbs/Kg and demo on/off choice.

(7) STOP/CLEAR Key

Touch this pad to stop the oven or clear entries.

(8) CLOCK Key

Touch this pad to enter the time of day.

(9) EXPRESS DEFROST Key

Touch this pad to defrost foods quickly.

(10) POWER Key

Touch this pad to set a cooking power.

(11) ADD MINUTE Key

Touch this pad to cook at 100% cook power for 1 to 99 minutes.

(12) KITCHEN TIMER Key

Touch this pad to use your microwave oven as a kitchen timer.

(13) START Key

Touch this pad to start all entries (except the functions which start automatically) and to turn Child Lock on or off.

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C. EASY USE CHART

(1) CLOCK

1. Touch STOP/CLEAR.

2. Touch CLOCK.

3. Touch numbers for correct time of day.

4. Touch START.

(2) KITCHEN TIMER

1. Touch STOP/CLEAR.

2. Touch KITCHEN TIMER.

3. Touch correct numbers for time.

4. Touch START.

(3) CHILD LOCK

To set:

1. Touch STOP/CLEAR.

2. Touch “START” more than 2 seconds. To cancel:

1. Touch STOP/CLEAR.

2. Touch “START” more than 2 seconds.

(4) ADD MINUTE

1. Touch STOP/CLEAR.

2. Touch ADD MINUTE.

(5) TIMED COOKING

1. Touch STOP/CLEAR.

2. Touch COOK TIME.

3. Touch numbers for cooking time.

4. Touch POWER.

5. Touch number for cooking power level.

6. Touch START.

(6) MULTI-STAGE COOKING

1. Touch STOP/CLEAR.

2. Touch COOK TIME.

3. Touch numbers for cooking time.

4. Touch POWER.

5. Touch number for cooking power level.

6. Repeat steps 2-5 to set 2nd cooking stage.

7. Touch START.

(7) SENSOR POPCORN

1. Touch STOP/CLEAR.

2. Touch POPCORN.

(8) SENSOR REHEAT

1. Touch STOP/CLEAR.

2. Touch REHEAT.

3. Touch number from 1 to 3 (Touch 1: DINNER PLATE, Touch 2: SOUP/SAUCE,

Touch 3: CASSEROLE)

(9) AUTO DEFROST

1. Touch STOP/CLEAR.

2. Touch AUTO DEFROST. Three different defrosting levels are provided. (MEAT, POULTRY, FISH)

3. Enter the weight of your food in decimal increments from 0.1 to 6.0 pounds.

4. Touch START

5. At beeping, turn food over by following the instructions in the manual.

6. After turning food over, touch START to resume defrosting.

(10) EXPRESS DEFROST

1. Touch STOP/CLEAR.

2. Touch EXPRESS DEFROST.

3. Touch number from 1 to 3 (Touch 1: MEAT, Touch 2: POULTRY, Touch 3: FISH)

(11) OPTION

1. Touch STOP/CLEAR.

2. Touch OPTION.

3. Touch number from 1 to 5 Touch 1: SOUND ON/OFF Touch 2: CLOCK ON/OFF Touch 3: SCROLL SPEED Touch 4: LBS/KG Touch 5: DEMO ON/OFF

4. Touch correct number for setting.

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8. PROCEDURE FOR MEASURING MICROWAVE ENERGY LEAKAGE

A. CAUTIONS

(1) Be sure to check a microwave emission prior to servicing

the oven if the oven is operative prior to servicing.

(2) The service personnel should inform the manufacturer,

importer, or assembler of any certified oven unit found to have a microwave emission level in excess of 5mW/cm.sq. and should repair any unit found to have excessive emission levels at no cost to the owner and should ascertain the cause of the excessive leakage. The service personnel should instruct the owner not to use the unit until the oven has been brought into compliance.

(3) If the oven operates with the door open, the service

personnel should;

- Tell the user not to operate the oven

- Contact the manufacturer and CDRH (Center for Devices and Radiological Health) immediately. NOTE: Address on CDRH Office of Compliance (HFZ-312) Center for Devices and Radiological Health 1390 Piccard Drive Rockville, Maryland 20850

(4) The service personnel should check all surface and vent

openings for microwave emission testing.

(5) Check for microwave energy leakage after every

servicing. The power density of the microwave radiation leakage emitted by the microwave oven should not exceed 1mW/cm.sq. And always start measuring of an unknown field to assure safety for operating personnel from radiation leakage. NOTE: The standard is 5mW/cm.sq. while in the customer’s home. 1mW/cm.sq. stated here is manufacturer’s own voluntary standard for units in customer’s home.

EQUIPMENT

• Electromagnetic energy leakage monitor (NARDA 8100B, HOLADAY HI 1501)

• 600cc glass beaker

• Glass thermometer 100°C

B. MEASURING MICROWAVE ENERGY LEAKAGE

(1) Pour 275±15cc of 20±5°C water in a beaker which is

graduated to 600 cc, and place the beaker in the center of the oven.

(2) Set the energy leakage monitor to 2,450 MHz and use it

following the manufacturer’s recommended test procedure to assure correct result.

(3) When measuring the leakage, always use the 2 inch

(5cm) spacer supplied with the probe. (4) Operate the oven at its maximum output. (5) Measure the microwave radiation using and

electromagnetic radiation monitor by holding the probe

perpendicular to the surface being measured. (See

Figure 7)

C. MEASUREMENT WITH THE OUTER CASE REMOVED

(1) When you replace the magnetron, measure for

microwave energy leakage before the outer case is

installed and after all necessary components are

replaced or adjusted. Special care should be taken in

measuring the following parts.

- Around the magnetron

- The waveguide

WARNING: AVOID CONTACTING ANY HIGH VOLTAGE

PARTS.

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Move probe along shaded area.

Probe scanning speed less than 2.5 cm/sec.

Figure 7

Figure 6

D. MEASUREMENT WITH A FULLY ASSEMBLED OVEN

(1) After all components, including the outer panels, are

fully assembled, measure for microwave energy leakage around the door viewing window, the exhaust opening and air inlet openings.

(2) Microwave energy leakage must not exceed the values

prescribed below.

NOTES:

Leakage with the outer panels removed - less than 5mW/cm.sq. Leakage for a fully assembled oven (Before the latch switch (primary) is interrupted) with the door in a slightly opened position - less than 1 mW/cm .sq.

E. NOTE WHEN MEASURING

(1) Do not exceed meter full scale deflection. (2) The test probe must be removed no faster than 1

inch/sec (2.5cm/sec) along the shaded area, otherwise a false reading may result.

(3) The test probe must be held with the grip portion of the

handle. A false reading may result if the operator’s hand is between the handle and the probe.

(4) When testing near a corner of the door, keep the probe

perpendicular to the surface making sure the probe horizontally along the oven surface, this may possibly cause probe damage.

F. RECORD KEEPING AND NOTIFICATION AFTER

MEASUREMENT

(1) After adjustment and repair of any microwave energy

interruption or microwave energy blocking device, record the measured values for future reference. Also enter the information on the service invoice.

(2) Should the microwave energy leakage not be more

than 1mW/cm.sq. after determining that all parts are in good condition, functioning properly and genuine replacement parts which are listed in this manual have been used.

(3) At least once a year, have the electromagnetic energy

leakage monitor checked for calibration by its manufacturer.

G. POWER OUTPUT MEASUREMENT

(1) Fill the test beaker with 59 ˚F(15 ˚C) ~ 75 ˚F(24 ˚C) 1 liter tap

water.

(2) Stir the water in the beaker with thermometer ( ˚F or ˚C) and

measure temperature as T1. (3) Place the beaker on the center of turntable. (4) Set for one (1) minute and three (3) seconds and operate

the oven at high power.

NOTE: The additional three (3) seconds is to allow the

magnetron to begin generating power.

(5) When the heating is finished, stir the water again with

thermometer and measure the temperature of water as T2. (6) Subtract T1 from T2, this will give you the temperature rise. (7) The microwave power output is within specification, if the

temperature rise is as shown below:

Temperature Rise

Line Voltage Degrees ˚F Degrees ˚C

120 V 18.9 ~ 25.2 10.5 ~ 14 108 V Min. 17.5 Min 9.7

(8) Power output will be influenced by line voltage of power

supply. Consequently, correct power output must be

measured within 120V AC ± 1 Volt while unit is operating.

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SPECIAL TIP

• This oven used the button head screws.

• When you remove the screws, using the tamper-resistant Torx driver have a pin-in-head.

Button Head

(Torx style 2)

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9. DISASSEMBLY INSTRUCTIONS

IMPORTANT NOTES:

UNIT MUST BE DISCONNECTED FROM ELECTRICAL OUTLET WHEN MAKING REPAIRS, RE-PLACEMENTS, ADJUSTMENTS AND CONTINUITY CHECKS. WAIT AT LEAST ONE MINUTE, UNTIL THE HIGH VOLTAGE CAPACITOR IN THE HIGH VOLTAGE POWER SUPPLY HAS FULLY DISCHARGED. THE CAPACITOR SHOULD BE DISCHARGED BY USING INSULATED WIRE - I.E. TEST PROBE CONNECTED TO 10KOHM RESISTOR IN SERIES TO GROUND. WHEN RECONNECTING THE WIRE LEADS TO ANY PART, MAKE SURE THE WIRING CONNECTIONS AND LEAD COLORS ARE CORRECTLY MATCHED ACCORDING TO THE OVERALL CIRCUIT DIAGRAM. (ESPECIALLY SWITCHES AND HIGH VOLTAGE CIRCUIT.)

A. REMOVING OUT CASE (Figures 8)

(1) Remove three screws from the rear section. (2) Remove one screw from the side section. (3) Push the outer case back about 1 inch (3cm). (4) Lift the case from the set.

B. REMOVING POWER AND CONTROL CIRCUIT

BOARD(Figure 9)

(1) Open the door. (2) Remove two screws, securing the circuit board. (3) Disconnect the lead wire from RELAY(RY2) on the

circuit board.

(4) Lift up and pull out control panel assembly carefully

from the cavity.

(5) Disconnect the lead wire from connector(CN1) on the

circuit board.

CAUTION: DISCHARGE THE HIGH VOLTAGE

CAPACITOR BEFORE SERVICING.

(6) Pull down and remove the circuit board from the control

panel.

(7) Remove the F.P.C connector from the terminal socket.

Lift up and pull out control panel

securing screw

ground screw

Remove screw

Figures 9

Figure 8

F.P.C.Connector

Control Panel

Circuit Board

C. DOOR GROSS ASSEMBLY REMOVAL

(1) Open the door. (2) Remove the choke cover cap very carefully with a flat-blade

screwdriver.

CAUTION : Be careful not to damage door seal plate with the

screwdriver.

(3) Lift up and pull out the door.

NOTE:

1. After replacing the door, be sure to check that the primary switch, monitor switch, and secondary switch operate normally.

2. After replacing the door, check for microwave energy leakage with a survey meter. Microwave energy must be below the limit of 5 mW/cm.sq. (with a 275 ml water load)

3. When mounting the door assembly to the oven assembly, be sure to adjust the door assembly parallel to the chassis. Also adjust so the door has no play between the inner door surface and oven frame assembly. If the door assembly is not mounted properly, microwaves may leak from the clearance between the door and the oven.

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Remove choke cover cap

Door seal plate

Remove choke cover cap

Figure 10

+ 35 hidden pages