SHARP R630D, R-630DK, R-630DW, R-630DS Service Manual

SERVICE MANUAL

S7017R630DPW/

MICROWAVE OVEN

R-630DK
R-630DW
R-630DS

MODELS

Breakfast

Linch on

One Dish

Bar

Baked

the Run

Popcorn

Sensor

Dinners

Custom

Potatoes

Reheat

Help

Sensor CookingMore from your Microwave

Super

Compu

Beverage

Defrost

Defrost

Vegetables

Main

Frozen

center

Kitchen

Entrees

Foods

Timer/Clock

12345

67890

Power

Minute

Level

PLus

STOP

START

Clear

Touch on

R-630DK
R-630DW
R-630DS

In the interest of user-safety the oven should be restored to its original
condition and only parts identical to those specified should be used.

WARNING TO SERVICE PERSONNEL: Microwave ovens con­tain circuitry capable of producing very high voltage and
current, contact with following parts may result in a severe,
possibly fatal, electrical shock. (High Voltage Capacitor, High
Voltage Power Transformer, Magnetron, High Voltage Recti­fier Assembly, High Voltage Harness etc..)

TABLE OF CONTENTS

Page
PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO

AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY...................INSIDE FRONT COVER

BEFORE SERVICING ......................................................................................................INSIDE FRONT COVER

WARNING TO SERVICE PERSONNEL................................................................................................................1

MICROWAVE MEASUREMENT PROCEDURE ...................................................................................................2

FOREWORD AND WARNING...............................................................................................................................3

PRODUCT SPECIFICATIONS ......................................................................................................... .....................4

GENERAL INFORMATION...................................................................................................................................4

OPERATION..........................................................................................................................................................6

TROUBLESHOOTING GUIDE ............................................................................................................................10

TEST PROCEDURE............................................................................................................................................ 12

TOUCH CONTROL PANEL .................................................................................................................................20

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ................................................................25

PICTORIAL DIAGRAM ........................................................................................................................................32

POWER UNIT CIRCUIT ......................................................................................................................................33

CPU UNIT CIRCUIT ............................................................................................................................................34

PRINTED WIRING BOARD .................................................................................................................................36

PARTS LIST ........................................................................................................................................................37

PACKING AND ACCESSORIES .........................................................................................................................39

SHARP CORPORATION

This document has been published to be used for after
sales service only.
The contents are subject to change without notice.

R-630DK
R-630DW
R-630DS

PRECAUTIONS TO BE OBSER VED BEFORE AND
DURING SER VICING TO A VOID POSSIBLE
EXPOSURE TO EXCESSIVE MICROW A VE
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 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 verify compliance with the Federal Performance Standard should be

performed on each oven prior to release to the owner.

BEFORE SERVICING

Before servicing an operative unit, perform a microwave emission check as per the Microwave
Measurement Procedure outlined in this service manual.
If microwave emissions level is in excess of the specified limit, contact SHARP ELECTRONICS
CORPORATION immediately @1-800-237-4277.

If the unit operates with the door open, service person should 1) tell the user not to operate the oven
and 2) contact SHARP ELECTRONICS CORPORATION and Food and Drug Administration's
Center for Devices and Radiological Health immediately.

Service personnel should inform SHARP ELECTRONICS CORPORATION of any certified unit found
with emissions in excess of 4mW/cm2. The owner of the unit should be instructed not to use the unit
until the oven has been brought into compliance.

W ARNING TO SER VICE PERSONNEL

Microwave ovens contain circuitry capable of pro­ducing very high voltage and current, contact with
following parts
fatal, electrical shock.

(Example)
High Voltage Capacitor, High Voltage Power Trans-

former, Magnetron, High Voltage Rectifier Assem­bly, High Voltage Harness etc..

Read the Service Manual carefully and follow all
instructions.

may result in a severe, possibly

Don't Touch !
Danger High Voltage

R-630DK
R-630DW
R-630DS

Before Servicing

1. Disconnect the power supply cord , and then
remove outer case.

2. Open the door and block it open.

3. Discharge high voltage capacitor.

WARNING:RISK OF ELECTRIC SHOCK.

DISCHARGE THE HIGH-VOLTAGE
CAPACITOR BEFORE SERVICING.

The high-voltage capacitor remains charged about 60
seconds after the oven has been switched off. Wait for 60
seconds and then short-circuit the connection of the high­voltage capacitor (that is the connecting lead of the high­voltage rectifier) against the chassis with the use of an
insulated screwdriver.

Whenever troubleshooting is performed the power supply
must be disconnected. It may, in some cases, be necessary
to connect the power supply after the outer case has been
removed, in this event,

1. Disconnect the power supply cord, and then remove
outer case.

2. Open the door and block it open.

3. Discharge high voltage capacitor.

4. Disconnect the leads to the primary of the power
transformer.

5. Ensure that the leads remain isolated from other
components and oven chassis by using insulation tape.

6. After that procedure, reconnect the power supply cord.

When the testing is completed,

1. Disconnect the power supply cord, and then remove
outer case.

2. Open the door and block it open.

3. Discharge high voltage capacitor.

4. Reconnect the leads to the primary of the power
transformer.

5. Reinstall the outer case (cabinet).

6. Reconnect the power supply cord after the outer case is
installed.

7. Run the oven and check all functions.

After repairing

1. Reconnect all leads removed from components during
testing.

2. Reinstall the outer case (cabinet).

3. Reconnect the power supply cord after the outer case is
installed.

4. Run the oven and check all functions.

Microwave ovens should not be run empty. To test for the
presence of microwave energy within a cavity, place a cup
of cold water on the oven turntable, close the door and set
the power to HIGH and set the microwave timer for two (2)
minutes. When the two minutes has elapsed (timer at zero)
carefully check that the water is now hot. If the water
remains cold, carry out Before Servicing procedure and re­examine the connections to the component being tested.

When all service work is completed and the oven is fully
assembled, the microwave power output should be checked
and a microwave leakage test should be carried out.

1

R-630DK
R-630DW
R-630DS

MICROW A VE MEASUREMENT PROCEDURE

A. Requirements:

1) Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a microwave oven
should not exceed 1mW/cm2 at any point 5cm or more from the external surface of the oven, measured prior to acquisition
by a purchaser, and thereafter (through the useful life of the oven), 5 mW/cm2 at any point 5cm or more from the external
surface of the oven.

2) Safety interlock switches Primary interlock relay and door sensing switch shall prevent microwave radiation emission in
excess of the requirement as above mentioned, secondary interlock switch shall prevent microwave radiation emission
in excess of 5 mW/cm2 at any point 5cm or more from the external surface of the oven.

B. Preparation for testing:
Before beginning the actual measurement of leakage, proceed as follows:

1) Make sure that the actual instrument is operating normally as specified in its instruction booklet.

Important:
Survey instruments that comply with the requirement for instrumentation as prescribed by the performance standard for
microwave ovens, 21 CFR 1030.10(c)(3)(i), must be used for testing.

2) Place the oven tray in the oven cavity.

3) Place the load of 275±15 ml (9.8 oz) of tap water initially at 20±5˚C (68˚F) in the center of the oven cavity.
The water container shall be a low form of 600 ml (20 oz) beaker with an inside diameter of approx. 8.5 cm (3-1/2 in.)
and made of an electrically nonconductive material such as glass or plastic.
The placing of this standard load in the oven is important not only to protect the oven, but also to insure that any leakage
is measured accurately.

4) Set the cooking control on Full Power Cooking Mode.

5) Close the door and select a cook cycle of several minutes. If the water begins to boil before the survey is completed,
replace it with 275 ml of cool water.

C. Leakage test:

Closed-door leakage test (microwave measurement)

1) Grasp the probe of the survey instrument and hold it perpendicular to the gap between the door and the body of the oven.

2) Move the probe slowly, not faster than 1 in./sec. (2.5 cm/sec.) along the gap, watching for the maximum indication on
the meter.

3) Check for leakage at the door screen, sheet metal seams and other accessible positions where the continuity of the metal
has been breached (eg., around the switches, indicator, and vents).
While testing for leakage around the door pull the door away from the front of the oven as far as is permitted by the closed
latch assembly.

4) Measure carefully at the point of highest leakage and make sure that the highest leakage is no greater than 4mW/cm2,
and that the secondary interlock switch does turn the oven OFF before any door movement.

NOTE: After servicing, record data on service invoice and microwave leakage report.

2

SERVICE MANUAL

R-630DK
R-630DW
R-630DS

MICROWAVE OVEN

R-630DK/ R-630DW/ R-630DS

FOREWORD

This Manual has been prepared to provide Sharp Electronics Corp.
Service Personnel with Operation and Service Information for the
SHARP MICROWAVE OVEN, R-630DK, R-630DW, R-630DS.

It is recommended that service personnel carefully study the entire
text of this manual so that they will be qualified to render satisfactory
customer service.

Check the interlock switches and the door seal carefully. Special
attention should be given to avoid electrical shock and microwave
radiation hazard.

WARNING

Never operate the oven until the following points are ensured.
(A) The door is tightly closed.
(B) The door brackets and hinges are not defective.
(C) The door packing is not damaged.
(D) The door is not deformed or warped.
(E) There is no other visible damage with the oven.

Servicing and repair work must be carried out only by trained service
personnel.

DANGER

Certain initial parts are intentionally not grounded and present
a risk of electrical shock only during servicing. Service
personnel - Do not contact the following parts while the
appliance is energized;
High Voltage Capacitor, Power Transformer, Magnetron, High
Voltage Rectifier Assembly, High Voltage Harness;
If provided, Vent Hood, Fan assembly, Cooling Fan Motor.

PRODUCT DESCRIPTION

GENERAL INFORMATION

OPERATION

TROUBLESHOOTING GUIDE AND
TEST PROCEDURE

TOUCH CONTROL PANEL

COMPONENT REPLACEMENT
AND ADJUSTMENT PROCEDURE

WIRING DIAGRAM

PARTS LIST

All the parts marked “*” on parts list are used at voltages more than
250V.

Removal of the outer wrap gives access to voltage above 250V.
All the parts marked “∆” on parts list may cause undue microwave

exposure, by themselves, or when they are damaged, loosened
or removed.

SHARP ELECTRONICS CORPORATION

SHARP PLAZA, MAHWAH,

NEW JERSEY 07430-2135

3

R-630DK
R-630DW
R-630DS

SPECIFICATION

ITEM DESCRIPTION

Power Requirements 120 Volts / 14 Amperes

60 Hertz
Single phase, 3 wire grounded

Power Output 1100 watts (IEC TEST PROCEDURE)

Operating frequency of 2450MHz

Case Dimensions Width 19-1/2"

Height 14"
Depth 20-5/8"

Cooking Cavity Dimensions Width 17-3/4"

Height 8-1/4"

1.4 Cubic Feet Depth 17"
Control Complement Touch Control System

Clock ( 1:00 - 12:59 )
Timer (0 - 99 min. 99 seconds)

Microwave Power for Variable Cooking
Repetition Rate;

P-HI..................................................Full power throughout the cooking time

P-90 .................................................................... approx. 90% of Full Power

P-80 .................................................................... approx. 80% of Full Power

P-70 .................................................................... approx. 70% of Full Power

P-60 .................................................................... approx. 60% of Full Power

P-50 .................................................................... approx. 50% of Full Power

P-40 .................................................................... approx. 40% of Full Power

P-30 .................................................................... approx. 30% of Full Power

P-20 .................................................................... approx. 20% of Full Power

P-10 .................................................................... approx. 10% of Full Power

P-0 .................................................... No power throughout the cooking time

Breakfast Bar pad, Lunch on the Run pad, One Dish Dinners pad
Super Defrost pad, Compu Defrost pad, Beverage Center pad
Sensor Cooking pads, Custom Help pad, Kitchen Timer/Clock pad
Number selection pads, Power Level pad, Minute Plus pad
STOP/Clear pad, START/Touch On pad

Oven Cavity Light Yes
Safety Standard UL Listed FCC Authorized

DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J

GENERAL INFORMATION

GROUNDING INSTRUCTIONS

This oven is equipped with a three prong grounding plug. It must be plugged into a wall receptacle that is properly installed
and grounded in accordance with the National Electrical Code and local codes and ordinances.
In the event of an electrical short circuit, grounding reduces the risk of electric shock by providing an escape wire for the
electric current.

WARNING: Improper use of the grounding plug can result in a risk of electric shock.

Electrical Requirements
The electrical requirements are a 120 volt 60 Hz, AC only,
15 or 20 amp. fused electrical supply. It is recommended that a separate circuit serving only this appliance be provided. When
installing this appliance, observe all applicable codes and ordinances.
A short power-supply cord is provided to reduce risks of becoming entangled in or tripping over a longer cord.

4

R-630DK

2

1

5

54

8

6

711 12

13

9

10

3

Breakfast

Bar

Sensor CookingMore from your Microwave

Vegetables

Popcorn

Linch on
the Run

Super

Defrost

Compu
Defrost

One Dish
Dinners

Beverage

center

Frozen
Foods

Main
Entrees

Kitchen

Timer/Clock

Sensor
Reheat

Baked

Potatoes

Custom

Help

Power
Level

STOP
Clear

START
Touch on

Minute

PLus

12345

67890

R-630DW
R-630DS

Where a two-pronged wall-receptacle is encountered, it is the personal
responsibility and obligation of the customer to contact a qualified
electrician and have it replaced with a properly grounded three-pronged
wall receptacle or have a grounding adapter properly grounded and
polarized. If the extension cord must be used, it should be a 3-wire, 15
amp. or higher rated cord. Do not drape over a countertop or table where
it can be pulled on by children or tripped over accidentally.

CAUTION: DO NOT UNDER ANY CIRCUMSTANCES CUT OR RE-

MOVE THE ROUND GROUNDING PRONG FROM THIS
PLUG.

OVEN DIAGRAM

1. Door handle
Pull to open door.

2. Auto-Touch control panel

3. Display: 99 minutes, 99 seconds

4. Oven door with see-through window

5. Safety door latches
The oven will not operate unless the
door is securely closed.

6. Door hinges

7. Door seals and sealing surface

8. Turntable motor shaft

9. Removable turntable support
Carefully place the turntable support
in the center of the oven floor.

10.Removable turntable
Place the turntable on the turntable
support cecurely. The turntable will
rotate clockwise or counterclockwise.
Only remove for cleaning.

11.Ventilation openings (Rear)

12.Oven light
It will light when oven is operating or
door is opened.

13.Wave guide cover: DO NOT REMOVE.

3-Pronged Plug

Grounding Pin

3-Pronged Receptacle

Grounded
Receptacle Box

TOUCH CONTROL PANEL

See note

Linch on

the Run

Compu
Defrost

One Dish

Dinners

Beverage

center

Popcorn

Sensor CookingMore from your Microwave

Vegetables

Baked

Potatoes

Main

Entrees

Sensor
Reheat

Frozen
Foods

Custom

Help

Kitchen

Timer/Clock

12345

67890

Breakfast

Bar

Super

Defrost

NOTE:

See note

Power

Level

STOP
Clear

See note

Minute

PLus

START

Touch on

The directed features are disabled after three minutes when the oven is not in use. These features are
automatically enabled when the door is opened and closed or the STOP/ CLEAR pad is pressed.

5

R-630DK
R-630DW
R-630DS

OPERATION

DESCRIPTION OF OPERATING SEQUENCE

The following is a description of component functions during
oven operation.

OFF CONDITION

Closing the door activates the door sensing switch and
secondary interlock switch. (In this condition, the monitor
switch contacts are opened.)
When oven is plugged in, 120 volts A.C. is supplied to the
control unit (Figure O-1).

1. The display will show "SHARP SIMPLY THE BEST
PRESS CLEAR AND PRESS CLOCK".To set any
program or set the clock, you must first touch the STOP/
CLEAR pad. The display will clear, and " : " will appear.

COOKING CONDITION

Program desired cooking time by touching the NUMBER
pads. Program the power level by touching the POWER
LEVEL pad and then a Number pad.
When the START pad is touched, the following operations
occur:

1. The contacts of relays are closed and components
connected to the relays are turned on as follows.
(For details, refer to Figure O-2)

RELAY CONNECTED COMPONENTS
RY-1 oven lamp/turntable motor/fan motor
RY-2 power transformer

2. 120 volts A.C. is supplied to the primary winding of the
power transformer and is converted to about 3.3 volts
A.C. output on the filament winding, and approximately
2400 volts A.C. on the high voltage winding.

3. The filament winding voltage heats the magnetron
filament and the H.V. winding voltage is sent to a voltage
doubler circuit.

4. The microwave energy produced by the magnetron is
channelled through the waveguide into the cavity feed­box, and then into the cavity where the food is placed to
be cooked.

5. Upon completion of the cooking time, the power
transformer, oven lamp, etc. are turned off, and the
generation of microwave energy is stopped. The oven
will revert to the OFF condition.

6. When the door is opened during a cook cycle, the
monitor switch, door sensing switch, secondary interlock
switch, relay (RY1) and primary interlock relay are
activated with the following results. The circuits to the
turntable motor, the cooling fan motor, and the high
voltage components are de-energized, the oven lamp
remains on, and the digital read-out displays the time still
remaining in the cook cycle when the door was opened.

7. The monitor switch electrically monitors the operation of
the secondary interlock switch and primary interlock
relay and is mechanically associated with the door so
that it will function in the following sequence.

(1)

When the door opens from the closed position, the primary
interlock relay (RY2) and secondary interlock switch open
their contacts. And contacts of the relay (RY1) remains
closed. Then the monitor switch contacts close.

(2) When the door is closed from the open position, the

monitor switch contacts open first. Then the contacts of
the secondary interlock switch and door sensing switch

close. And contacts of the relay (RY1) open.
If the secondary interlock switch and primary interlock relay
(RY2) fail with the contacts closed when the door is opened,
the closing of the monitor switch contacts will form a short
circuit through the monitor fuse, secondary interlock switch,
relay (RY1) and primary interlock relay (RY2), causing the
monitor fuse to blow.

POWER LEVEL 0 PERCENT TO 90 PERCENT
COOKING

When Variable Cooking Power is programmed, the 120
volts A.C. is supplied to the power transformer intermittently
through the contacts of relay (RY-2) which is operated by
the control unit within a 32 second time base. Microwave
power operation is as follows:

VARI-MODE ON TIME OFF TIME

100 PERCENT 32 sec. 0 sec.

90 PERCENT 30 sec. 2 sec.

80 PERCENT 26 sec. 6 sec.

70 PERCENT 24 sec. 8 sec.

60 PERCENT 22 sec. 10 sec.

50 PERCENT 18 sec. 14 sec.

40 PERCENT 16 sec. 16 sec.

30 PERCENT 12 sec. 20 sec.

20 PERCENT 8 sec. 24 sec.

10 PERCENT 6 sec. 26 sec.

0 PERCENT 0 sec. 32 sec.
Note: The ON/OFF time ratio does not correspond with

the percentage of microwave power, because
approx. 2 seconds are needed for heating of the
magnetron filament.

SENSOR COOKING CONDITION

Using the SENSOR function, the food is cooked without
figuring time, power level or quantity. When the oven senses
enough steam from the food, it relays the information to its
microprocessor which will calculate the remaining cooking
time and power level needed for best results. When the food
is cooked, water vapor is developed. The sensor “senses”
the vapor and its resistance increases gradually. When the
resistance reaches the value set according to the menu,
supplementary cooking is started. The time of supplemen­tary cooking is determined by experiment with each food
category and inputted into the LSI.

6

An example of how sensor works: (POTATOES)

1. Potates at room temperature. Vapor is emitted very
slowly.

MICROWAVE

2. Heat Potates. Moisture and humidity is emitted rapidly.
You can smell the aroma as it cooks.

AH SENSOR

MICROWAVE

R-630DK
R-630DW
R-630DS

3. Sensor detects moisture and humidity and calculates
cooking time and variable power.

Cooking Sequence.

1. Operate the oven in sensor cooking mode by referring to
the operation manual.

NOTE: The oven should not be operated on SENSOR

immediately after plugging in the unit. Wait two
minutes before cooking on SENSOR.

2. The coil of shut-off relay (RY-1) is energized, the turntable
motor, oven lamp and cooling fan motor are turned on,
but the power transformer is not turned on.

3. After about 16 seconds, the cook relay (RY-2) is
energized. The power transformer is turned on,
microwave energy is produced and first stage is started.
The 16 seconds is the cooling time required to remove
any vapor from the oven cavity and sensor.

NOTE: During this first stage, do not open the door or touch

STOP/CLEAR pad.

4. When the sensor detects the vapor emitted from the
food, the display switches over to the remaining cooking
time and the timer counts down to zero.
At this time, the door may be opened to stir, turn, or
season food.

5. When the timer reaches zero, an audible signal sounds.
The shut-off relay and cook relay are de-energized and
the power transformer, oven lamp, etc. are turned off.

6. Opening the door or touching the STOP/CLEAR pad, the
time of day will reappear on the display and the oven will
revert to an OFF condition.

7

R-630DK
R-630DW
R-630DS

SCHEMATIC

NOTE: CONDITION OF OVEN

1. DOOR CLOSED

2. CLOCK APPEARS ON DISPLAY

120V AC
60 Hz

THERMAL
CUT-OUT (OVEN)

A2

A1

CONTROL UNIT

OVEN

OL FM

LAMP

SECONDARY
INTERLOCK
SWITCH

THERMAL
CUT-OUT (MG.)

(RY-1)

TTM

TURN­TABLE
MOTOR

N.O.

FAN
MOTOR

(RY-2)

COM.COM.

PRIMARY
INTERLOCK
RELAY

B2 B1

DOOR
SENSING
SWITCH

GRN

MONITOR
FUSE 20A

Figure O-1. Oven Schematic-Off Condition

SCHEMATIC

NOTE: CONDITION OF OVEN

1. DOOR CLOSED

2. COOKING TIME PROGRAMMED

3. VARIABLE COOKING CONTROL "P-HI" (100%)

4. "START" PAD TOUCHED

AH SENSOR

POWER
TRANSFORMER

CAPACITOR 0.94µF

AC 2200V

RECTIFIER

MAGNETRON

N.O.

F3

F2

F1

MONITOR
SWITCH

120V AC
60 Hz

GRN

MONITOR
FUSE 20A

THERMAL
CUT-OUT (OVEN)

A2

A1

CONTROL UNIT

OVEN

OL FM

LAMP

SECONDARY
INTERLOCK
SWITCH

THERMAL
CUT-OUT (MG.)

TTM

(RY-1)

TURN­TABLE
MOTOR

COM

N.O..

FAN
MOTOR

(RY-2)

COM.

PRIMARY
INTERLOCK
RELAY

B2 B1

DOOR
SENSING
SWITCH

N.O.

F3

F2

F1

MONITOR
SWITCH

AH SENSOR

POWER
TRANSFORMER

Figure O-2. Oven Schematic-Cooking Condition

CAPACITOR 0.94µF

AC 2200V

RECTIFIER

MAGNETRON

8

DESCRIPTION AND FUNCTION OF COMPONENTS

R-630DK
R-630DW
R-630DS

DOOR OPEN MECHANISM

The door is opened by pulling the door. Refer to the Figure
D-1.

Door

Latch
Heads

Secondary
Interlock Switch

Latch Hook

Door Sensing
Switch

Monitor Switch

Figure D-1. Door Open Mechanism

DOOR SENSING AND SECONDARY INTERLOCK
SWITCHES

The secondary interlock switch is mounted in the lower
position of the latch hook and the door sensing switch in the
primary interlock system is mounted in the upper position of
the latch hook. They are activated by the latch heads on the
door. When the door is opened, the switches interrupt the
power to all high voltage components. A cook cycle cannot
take place until the door is firmly closed thereby activating
both interlock switches. The primary interlock system con­sists of the door sensing switch and primary interlock relay
located on the control circuit board.

MONITOR SWITCH

The monitor switch is activated (the contacts opened) by the
latch head on the door while the door is closed. The switch
is intended to render the oven inoperative, by means of
blowing the monitor fuse, when the contacts of the primary
interlock relay (RY2) and secondary interlock switch fail to
open when the door is opened.

Functions:

1. When the door is opened, the monitor switch contact
close (to the ON condition) due to their being normally
closed. At this time the primary interlock relay (RY2) and
secondary interlock switch are in the OFF condition
(contacts open) due to their being normally open contact
switches.

2. As the door goes to a closed position, the monitor switch
contacts are first opened and then the door sensing
switch and the secondary interlock switch contacts close.
(On opening the door, each of these switches operate
inversely.)

3. If the door is opened, and the primary interlock relay
(RY2) and secondary interlock switch contacts fail to
open, the monitor fuse blows simultaneously with closing
of the monitor switch contacts.

CAUTION: BEFORE REPLACING A BLOWN MONITOR

FUSE TEST THE DOOR SENSING SWITCH,
PRIMARY INTERLOCK RELAY (RY2), RELAY
(RY1), SECONDARY INTERLOCK SWITCH
AND MONITOR SWITCH FOR PROPER OP­ERATION. (REFER TO CHAPTER "TEST PRO­CEDURE").

NOTE: MONITOR FUSE AND MONITOR SWITCH ARE

REPLACED AS AN ASSEMBLY.

TURNTABLE MOTOR

The turntable motor rotates the turntable located on the
bottom of the oven cavity, so that the foods on the turntable
cook evenly during cooking. The turntable may turn in either
direction.

COOLING FAN MOTOR

The cooling fan motor drives a blade which draws external
cool air. This cool air is directed through the air vanes
surrounding the magnetron and cools the magnetron. This
air is channelled through the oven cavity to remove steam
and vapors given off from the heating foods. It is then
exhausted through the exhausting air vents at the oven
cavity.

MONITOR FUSE

1. The monitor fuse blows when the contacts (COM-NO) of
the primary interlock relay (RY2) and secondary interlock
switch remain closed with the oven door open and when
the monitor switch closes.

2. If the wire harness or electrical components are short­circuited, this monitor fuse blows to prevent an electric
shock or fire hazard.

OVEN THERMAL CUT-OUT

The thermal cut-out, located on the top of the oven cavity, is
designed to prevent damage to the oven by fire. If the food
load is overcooked, by either error in cook time or defect in
the control unit, the thermal cut-out will open.
Under normal operation, the oven thermal cut-out remains
closed. However, when abnormally high temperatures are
reached within the oven cavity, the oven thermal cut-out will
open at 257˚F(125˚C), causing the oven to shut down.

MAGNETRON THERMAL CUT-OUT

The thermal cut-out located near the magnetron is designed
to prevent damage to the magnetron if an over heated
condition develops in the tube due to cooling fan failure,
obstructed air guide, dirty or blocked air intake, etc.
Under normal operation, the thermal cut-out remains closed.
However, when abnormally high temperatures are reached
within the magnetron, the thermal cut-out will open at
257˚F(125˚C) causing the oven to shut down.

9

R-630DK
R-630DW
R-630DS

TROUBLESHOOTING GUIDE

Never touch any part in the circuit with your hand or an uninsulated tool while the power supply is connected.

When troubleshooting the microwave oven, it is helpful to follow the Sequence of Operation in performing the checks. Many
of the possible causes of trouble will require that a specific test be performed. These tests are given a procedure letter which
will be found in the "Test Procedure "section.

IMPORTANT: If the oven becomes inoperative because of a blown monitor fuse, check the monitor switch, relay (RY1)

primary interlock relay (RY2), door sensing switch and secondary interlock switch before replacing the
monitor fuse. If the monitor fuse is replaced, the monitor switch must also be replaced. Use part FFS­BA023WRK0 as an assembly.

IMPORTANT: Whenever troubleshooting is performed with the power supply cord disconnected. It may, in some cases,

be necessary to connect the power supply cord after the outer case has been removed, in this event,

1. Disconnect the power supply cord, and then remove outer case.

2. Open the door and block it open.

3. Discharge high voltage capacitor.

4. Disconnect the leads to the primary of the power transformer.

5. Ensure that the leads remain isolated from other components and oven chassis by using insulation tape.

6. After that procedure, reconnect the power supply cord.

When the testing is completed

1. Disconnect the power supply cord, and then remove outer case.

2. Open the door and block it open.

3. Discharge high voltage capacitor.

4. Reconnect all leads removed from components during testing.

5. Reinstall the outer case (cabinet).

6. Reconnect the power supply cord after the outer case is installed.

7. Run the oven and check all functions.

10

R-630DK
R-630DW
R-630DS

CK = Check / RE = Replace

CONDITION

OFF
CONDITION

SENSOR
COOKING
CONDITION

TEST PROCEDURE

AND

POSSIBLE CAUSE

DEFECTIVE PARTS

PROBLEM

Home fuse or circuit breaker blows
when power cord is plugged into wall
receptacle

Monitor fuse blows when power cord
is plugged into wall receptacle.

All letters and indicators do not ap­pear in display when power cord is
first plugged into wall outlet.

Display does not operate properly
when STOP/CLEAR key is touched.
(Buzzer should sound and ":" or time
of day should appear in display.)

Oven lamp does not light when door
is opened.

Oven lamp does not go out when
door is closed.

Oven lamp lights but fan motor and
turntable motor do not operate.

Oven does not go into cook cycle
when START pad is touched

Oven seems to be operating but little
or no heat is produced in oven load.
(Food incompletely cooked or not
cooked at all at end of cook cycle.)

Oven goes into a cook cycle but ex­tremely uneven heating is produced
in oven load (food).

Oven does not cook properly when
programmed for Cooking Power P­50 mode. (Operates properly on Cook­ing Power P-HI (100%) mode.)

Oven goes into COMPU DEFROST
but food is not defrosted well.

AH sensor does not end during sen­sor cooking condition. (Oven does
not shut off after a cup of water is
boiling by sensor cooking.)

Oven stops at 16 sec. after setting.

RE RE

ABCDEFFGH

SHORT IN POWER CORD

SHORT OR OPENED WIRING

MAGNETRON

POWER TRANSFORMER

H.V. RECTIFIER ASSEMBLY

RE RE

HIGH VOLTAGE CAPACITOR

THERMAL CUT-OUT

PRIMARY INTERLOCK SYSTEM

SECONDARY INTERLOCK SWITCH

MONITOR SWITCH

MONITOR FUSE

OVEN LAMP OR SOCKET

CKICKCKCK

COOLING FAN MOTOR

TURNTABLE MOTOR

CONTROL UNIT

WRONG OPERATION

LOW VOLTAGE

DIRTY OVEN CAVITY

JKLMN

KEY UNIT

RELAY (RY1)

COMPU DEFROST

FOIL PATTERN ON PWB.

AH SENSOR

11

R-630DK
R-630DW
R-630DS

TEST PROCEDURES

PROCEDURE

LETTER

A MAGNETRON ASSEMBLY TEST

1. Disconnect the power supply cord, and then remove outer case.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. To test for an open filament, isolate the magnetron from the high voltage circuit. A continuity check
across the magnetron filament leads should indicate less than 1 ohm.

5. To test for a shorted magnetron, connect the ohmmeter leads between the magnetron filament leads
and chassis ground. This test should indicate an infinite resistance. If there is little or no resistance
the magnetron is grounded and must be replaced.

6. Reconnect all leads removed from components during testing.

7. Reinstall the outer case (cabinet).

8. Reconnect the power supply cord after the outer case is installed.

9. Run the oven and check all functions.

MICROWAVE OUTPUT POWER

The following test procedure should be carried out with the microwave oven in a fully assembled
condition (outer case fitted).

HIGH VOLTAGES ARE PRESENT DURING THE COOK CYCLE, SO EXTREME CAUTION SHOULD
BE OBSERVED.

Power output of the magnetron can be measured by performing a water temperature rise test. This test
should only be used if above tests do not indicate a faulty magnetron and there is no defect in the following
components or wiring: silicon rectifier, high voltage capacitor and power transformer. This test will require
a 16 ounce (453cc) measuring cup and an accurate mercury thermometer or thermocouple type
temperature tester. For accurate results, the following procedure must be followed carefully:

COMPONENT TEST

1. Fill the measuring cup with 16 oz. (453cc) of tap water and measure the temperature of the water with
a thermometer or thermocouple temperature tester. Stir the thermometer or thermocouple through
the water until the temperature stabilizes. Record the temperature of the water.

2. Place the cup of water in the oven. Operate oven at POWER P-HI(HIGH) selecting more than 60
seconds cook time. Allow the water to heat for 60 seconds, measuring with a stop watch, second hand
of a watch or the digital read-out countdown.

3. Remove the cup from the oven and again measure the temperature, making sure to stir the
thermometer or thermocouple through the water until the maximum temperature is recorded.

4. Subtract the cold water temperature from the hot water temperature. The normal result should be 32.1
to 59.7˚F(17.9 to 33.2˚C) rise in temperature. If the water temperatures are accurately measured and
tested for the required time period the test results will indicate if the magnetron tube has low power
output (low rise in water temperature) which would extend cooking time or high power output (high
rise in water temperature) which would reduce cooking time. Because cooking time can be adjusted
to compensate for power output, the magnetron tube assembly should be replaced only if the water
temperature rise test indicates a power output well beyond the normal limits. The test is only accurate
if the power supply line voltage is 120 volts and the oven cavity is clean.

B POWER TRANSFORMER TEST

1. Disconnect the power supply cord, and then remove outer case.

2. Open the door and block it open.

3. Discharge the high voltage capacitor.

4. Disconnect the primary input terminals and measure the resistance of the transformer with an
ohmmeter. Check for continuity of the coils with an ohmmeter. On the R x 1 scale, the resistance of
the primary coil should be less than 1 ohm and the resistance of the high voltage coil should be
approximately 75 ohms; the resistance of the filament coil should be less than 1 ohm.

5. Reconnect all leads removed from components during testing.

6. Reinstall the outer case (cabinet).

7. Reconnect the power supply cord after the outer case is installed.

8. Run the oven and check all functions.

12