R-820BK
R-820BW
SERVICE MANUAL
S5812R820BPW/
DOUBLE GRILL
CONVECTION
MICROWAVE OVEN
MODELS
COOK
HELP
Iinteractive
PIZZA
BAKE
CUSTOM
HELP
GRILL
COMPU ROAST
COOK DEFROST
CONVEC
GRILL
POPCORN
REHEAT
ROAST
R-820BK
R-820BW
MINUTE
PLUS
1 2 3 4 5
6 7 8 9 O
100˚ F
150˚ F
350˚ F
375˚ F
KITCHEN
TIMER
STOP
CLEAR
GRILL
275˚ F
300˚ F
325˚ F
400˚ F
425˚ F
450˚ F
CLOCK
POWER
LEVEL
START
TOUCH ON
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.
2 CONVECTIO
N
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 ............................................................................................................................ 13
TEST PROCEDURE ............................................................................................................................................ 15
TOUCH CONTROL PANEL ................................................................................................................................. 24
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ................................................................ 30
PICTORIAL DIAGRAM ........................................................................................................................................ 37
POWER UNIT CIRCUIT ...................................................................................................................................... 38
CPU UNIT CIRCUIT ............................................................................................................................................ 39
PRINTED WIRING BOARD ................................................................................................................................. 40
PARTS LIST ........................................................................................................................................................ 41
PACKING AND ACCESSORIES ......................................................................................................................... 43
SHARP CORPORATION
This document has been published to be used for after
sales service only.
The contents are subject to change without notice.
R-820BK
R-820BW
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 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 releasing oven 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.
R-820BK
R-820BW
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.
(Example)
High Voltage Capacitor, High Voltage Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc..
Read the Service Manual carefully and follow all
instructions.
Don't Touch !
Danger High Voltage
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.
Before Servicing
1. Disconnect the power supply cord ,
remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
and then
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.
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.
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.
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 microwave leakage test should be carried out.
1
R-820BK
R-820BW
MICROWAVE 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
R-820BK
R-820BW
SERVICE MANUAL
PRODUCT DESCRIPTION
DOUBLE GRILL
CONVECTION
MICROWAVE OVEN
GENERAL INFORMATION
R-820BK / R-820BW
FOREWORD
This Manual has been prepared to provide Sharp Electronics Corp.
Service Personnel with Operation and Service Information for the
SHARP MICROWAVE OVEN, R-820BK, R-820BW.
OPERATION
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.
TROUBLESHOOTING GUIDE AND
TEST PROCEDURE
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.
TOUCH CONTROL PANEL
COMPONENT REPLACEMENT
AND ADJUSTMENT PROCEDURE
WIRING DIAGRAM
Servicing and repair work must be carried out only by trained service
personnel.
PARTS LIST
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.
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-820BK
R-820BW
SPECIFICATION
ITEM
Power Requirements
Power Output
DESCRIPTION
120 Volts
12.5 Amperes (Microwave) / 13.0 Amperes (Grill/ Convection)
60 Hertz / Single phase, 3 wire grounded
900 watts (IEC 705 Test Procedure)
Operating frequency of 2450MHz
Top Heater Power Output
Top & Bottom Heater Power Output
1000 Watts
1500 Watts
Case Dimensions
Cooking Cavity Dimensions
(0.9 Cubic Feet )
Width 20-1/2"
Height 12-1/8"
Depth 19-3/4"
Width 13-7/8"
Height 7-1/2"
Depth 14-1/2"
Control Complement
Touch Control System
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
Grill Cooking (GRILL) ........ Top and Bottom Grill Mode / Top Grill Mode only
Convection Cooking (CONVEC) .......................... 100 - 450˚F Temp. control
Roast Cooking (ROAST) .......................... 325˚F with 30% microwave power
CUSTOM HELP pad, COMPU COOK/ BAKE/ PIZZA/ GRILL/ ROAST pads
COMPU DEFROST pad, CONVEC pad, GRILL pad, ROAST pad
POPCORN pad, REHEAT pad, MINUTE PLUS pad
Number and temperature selection pads, KITCHEN TIMER pad, CLOCK pad
STOP/CLEAR pad, POWER LEVEL pad, START / TOUCH ON pad
Oven Cavity Light
Safety Standard
Yes
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 115 -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.
4
R-820BK
R-820BW
A short power-supply cord is provided to reduce risks of becoming
entangled in or tripping over a longer cord.
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.
Grounded
Receptacle Box
3-Pronged Plug
Grounding Pin
3-Pronged Receptacle
CAUTION: DO NOT UNDER ANY CIRCUMSTANCES CUT OR REMOVE THE ROUND GROUNDING PRONG FROM THIS
PLUG.
OVEN DIAGRAM
1. Oven light
2. Top heaters (Grill heaters)
3. Oven door with see through window
4. Door hinges
5. Safety door latches
6. Door seals and sealing surfaces
7. Bottom heater
8. Oven cavity
9. Turntable motor shaft
10.Ventilation openings
11.Waveguide cover
12.One touch door opening button
13.Auto-Touch control panel
14.Time display
Turntable
support
15.Power supply cord
16.Outer cabinet
17.Menu label
4
2
u
t
0
r
0
1
q
8 9
5
e
y
3
0
6
7
5
Turntable
w
0
TOUCH CONTROL PANEL
Rack
Bottom
heater
COOK
HELP
Turntable
motor shaft
NOTE:
1. Ensure that the bottom heater is in the lowest
position as shown in the figure, as it is possible to
move it up and down to help with cleaning.
2. Place the turntable support over the turntable motor
shaft on the floor of the cavity.
3. Then place the turntable onto the turntable support.
Iinteractive
PIZZA
BAKE
CUSTOM
HELP
GRILL
COMPU ROAST
COOK DEFROST
CONVEC
GRILL
ROAST
POPCORN
REHEAT
MINUTE
PLUS
1 2 3 4 5
6 7 8 9 O
100˚ F
150˚ F
275˚ F
300˚ F
325˚ F
350˚ F
375˚ F
400˚ F
425˚ F
450˚ F
KITCHEN
TIMER
STOP
CLEAR
5
CLOCK
POWER
LEVEL
START
TOUCH ON
R-820BK
R-820BW
OPERATION
DESCRIPTION OF OPERATING SEQUENCE
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 relay
(RY5), primary interlock relay(RY2) and secondary
interlock switch open their contacts. And contacts of the
relay(RY6) 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(RY6) 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(RY6) and primary interlock relay(RY2), causing the
monitor fuse to blow.
The following is a description of component functions during
oven operation.
OFF CONDITION
Closing the door activates 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
,
,
,
,,
,
,
,
and
.
To set any program or set the clock, you must first touch
the STOP/CLEAR pad. The display will clear, and " : "
will appear.
MICROWAVE 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:
POWER LEVEL P-0 TO P-90 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:
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
RY-2
RY-5
RY-6
VARI-MODE
Power 10(P-HI)
(100% power)
Power 9(P-90)
(approx. 90% power)
Power 8(P-80)
(approx. 80% power)
Power 7(P-70)
(approx. 70% power)
Power 6(P-60)
(approx. 60% power)
Power 5(P-50)
(approx. 50% power)
Power 4(P-40)
(approx. 40% power)
Power 3(P-30)
(approx. 30% power)
Power 2(P-20)
(approx. 20% power)
Power 1(P-10)
(approx. 10% power)
Power 0(P-0)
(0% power)
CONNECTED COMPONENTS
Power transformer
Fan motor
Oven lamp/ Turntable motor
2. 120 volts A.C. is supplied to the primary winding of the
power transformer and is converted to about 3.1 volts
A.C. output on the filament winding, and approximately
2260 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, monitor
switch, door sensing switch, secondary interlock switch,
relay (RY5), relay (RY6) and primary interlock relay(RY2)
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
Note:
ON TIME
32 sec.
OFF TIME
0 sec.
30 sec.
2 sec.
26 sec.
6 sec.
24 sec.
8 sec.
22 sec.
10 sec.
18 sec.
14 sec.
16 sec.
16 sec.
12 sec.
20 sec.
8 sec.
24 sec.
6 sec.
26 sec.
0 sec.
32 sec.
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.
GRILL COOKING CONDITIONS
The oven has two grill cooking conditions. They are the TOP
HEATER mode and TOP AND BOTTOM HEATER mode.
6
R-820BK
R-820BW
TOP AND BOTTOM HEATER MODE
In this mode, the food is cooked by both the top heaters and
bottom heater. Press the GRILL pad and number "1" pad
and then enter the cooking time by pressing the number
pads. When the START pad is pressed, the following
operations occur (Figure O-3a):
1. The relays(RY3, RY4, RY5 and RY6) are energized.
2. The numbers of the digital read-out start the count down
to zero.
3. Then the top heaters, bottom heater, turntable motor,
oven lamp and fan motor are energized.
4. Now, the food is grilled by the top heaters and the bottom
heater.
5. Upon completion of the selected cooking time, audible
signal sounds and the contacts of relays(RY3, RY4 and
RY6) are opened, then the top heating elements, bottom
heating element, turntable motor and oven lamp are deenergized. But the relay(RY5) stays closed and the fan
motor operates for 5 minutes. But if the cooking time is
less than 2 minutes the relay(RY5) will not stay closed.
NOTE: If the total grill cooking time is beyond 35 minutes,
the relay(RY1) is energized and the convection
motor is energized.
work with 100% power. The relay(RY1) and the
convection motor are not energized at this preheating
condition.
NOTE: If the cavity temperature is lower than 100˚F(38C) at
4 minutes and 15 seconds after the preheat is
started, the control unit judges that the thermistor is
opened. And the oven is stopped.
4. When the oven temperature reaches the selected preheat
temperature, the following operations occur:
4-1 The relays(RY3 and RY4) are de-energized by the
control unit temperature circuit and thermistor,
opening the circuit to the heating element.
4-2. The oven will continue to function for 30 minutes,
turning the top heaters and the bottom heater on
and off, as needed to maintain the selected preheat
temperature. The oven will shutdown completely
after 30 minutes
CONVECTION TIME COOKING CONDITION
5. When the preheat temperature is reached, a beep signal
will sound indicating that the holding temperature has
been reached in the oven cavity. Open the door and
place the food to be cooked in the oven. When the
START pad is touched, the following operations occur:
6. The numbers on the digital read-out start to count down
to zero.
7. The relays(RY1, RY5 and RY6) are energized and the
oven lamp, turntable motor, cooling fan motor and
convection motor are energized.
8. The relays(RY3 and RY4) are energized (if the cavity
temperature is lower than the selected temperature) and
the main supply voltage is applied to the heating element
to return to the selected cooking temperature. The top
heaters and the bottom heater work in accordance with
the following table while the heaters are energized.
TOP HEATER MODE
In this mode, the food is cooked by the top heaters. Press the
GRILL pad and number "2" pad and then enter the cooking
time by pressing the number pads. When the START pad is
pressed, the following operations occur (Figure O-3b):
1. The relays(RY3, RY5 and RY6) are energized.
2. The numbers of the digital read-out start the count down
to zero.
3. Then the top heaters, turntable motor, oven lamp and fan
motor are energized.
4. Now, the food is grilled by the top heaters.
5. Upon completion of the selected cooking time, audible
signal sounds and the contacts of relays(RY3 and RY6)
are opened, then the top heaters, turntable motor and
oven lamp are de-energized. But the relay(RY5) stays
closed and the fan motor operates for 5 minutes. But if
the cooking time is less than 2 minutes the relay(RY5)
will not stay close.
NOTE: If the total grill cooking time is beyond 35 minutes,
the relay(RY1) is energized and the convection
motor is energized.
Selected Temperature (˚F)
CONVECTION COOKING CONDITION WITH PREHEAT
Touch the CONVEC pad and select the convection with
preheat mode by touching the number "1" pad.
1. Program desired convection temperature by touching
the Temperature pad. Enter the cooking time by touching
the number pads. When the START pad is touched, the
following operations occur:
PREHEATING CONDITION
2. The coil of shut-off relays (RY5 and RY6) are energized,
the oven lamp, cooling fan motor and turntable motor are
turned on.
3. The coil of relays(RY3 and RY4) are energized by the
control unit, and the top heaters and the bottom heater
Top Heaters
Power (%)
Bottom Heaters
Power (%)
100
150
20
20
10(after 3min. 0%)
10
275
300
325
350
40
40
50
50
40
50
50
60
375
400
425
60
60
70
60
70
70
450
70
80
9. Upon completion of the cooking time, the audible signal
will sound, and oven lamp, turntable motor, cooling fan
motor and convection motor are de-energized. At the
end of the convection cycle, if the cavity air temperature
is above 250˚F(120˚C), the circuit to RY5 will be
maintained (by the thermistor circuit) to continue operation
of the cooling fan motor until the temperature drops
below 220˚F(104˚C), at which time the relay will be deenergized, turning off the fan motor. Relay RY1 will
however, open as soon as the convection cycle has
ended, turning off the convection fan motor.
7
R-820BK
R-820BW
ROAST COOKING CONDITION
FIRE SENSING FEATURE (MICROWAVE MODE)
Touch the ROAST pad once. And then program desired
cooking time by touching the number pads. The ROAST
pad is preprogrammed for 325˚F with 30% microwave
power.
NOTE: The microwave power can not be changed. To
change the temperature, touch the ROAST pad
twice. When the display says "SELECT TEMP",
touch desired temperature pad.
When the START pad is pressed, the following operations
occur:
1. The numbers on the digital read-out start to count down.
2. The shut-off relays(RY1, RY5 and RY6) are energized,
turning on the oven lamp, turntable motor, cooling fan
motor and convection motor.
3. The microwave relay(RY2) is energized for 16 seconds
within a 48 second time base.
4. The heater relays(RY3 and RY4) are energized
intermittently within a 48 second time base. The power
output is set in accordance with the following table.
This model incorporates a sensing feature which will stop
the oven's operation if there is a fire in the oven cavity during
microwave cooking.
This is accomplished by the LSI repeatedly measuring the
voltage across the temperature measurement circuit (thermistor) during it's 32-seconds time base comparing the
obtained voltage measurements. If the most recent voltage
measured is 700mV greater than the previous voltage
measured, the LSI judges it as a fire in the oven cavity and
switches off the relays to the power transformer, fan motor,
oven lamp and turntable motor. The LSI also stops counting
down. Please refer to the following section for a more
detailed description.
Operation
Please refer to the timing diagrams below.
1. The thermistor operates within a 32-seconds time base
and it is energized for three (3) seconds and off for 29
seconds. Two (2) seconds after the thermistor is
energized, the voltage across the temperature
measurement circuit is sampled by the LSI and twenty
one (21) seconds after the thermistor is cut off the LSI
turns on the cooling fan for six (6) seconds.
2. The above procedure is repeated. If the difference
between the first voltage measured (in step 1) and the
voltage measured when the procedure is repeated (step
2) is greater than 700mV the LSI makes the judgment
that there is a fire in the oven cavity and will switch off the
relays to the power transformer, fan motor, oven lamp
and turntable motor. The LSI also stops counting down.
3. Once the fire sensor feature has shut the unit down, the
programmed cooking cycle may be resumed by pressing
the "START" pad or the unit may be reset by pressing the
"CLEAR" pad.
Selected Temperature (˚F)
Top Heaters
Power (%)
Bottom Heaters
Power (%)
100
20
40
150
275
300
30
50
60
50
60
70
325
350
375
70
70
70
70
70
70
400
425
450
70
70
70
70
70
70
5. The microwave relay(RY2) and the heater relays(RY3
and RY4) are not energized simultaneously.
0 2
ON/OFF TIME RATIO
THERMISTOR
ON TIME
48 sec.
44 sec.
40 sec.
36 sec.
32 sec.
26 sec.
22 sec.
16 sec.
12 sec.
8 sec.
64 (sec.)
3 sec.
OFF
In grill cooking, convection cooking or roast cooking, the top
heaters, bottom heater or magnetron operate whithin a 48
second time base. The following table is the ON / OFF time
ratio at each power output of the top heaters, bottom heater
or magnetron.
POWER OUTPUT
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
ON
32
SENSING ON
VOLTAGE OFF
Sensing the voltage across temperature
measurement circuit.
OFF TIME
0 sec.
4 sec.
8 sec.
12 sec.
16 sec.
22 sec.
26 sec.
32 sec.
36 sec.
40 sec.
8
THERMAL
CUT-OUT
(MAG.)
9
RY3
RY4
COM.
COM.
SECONDARY
INTERLOCK SWITCH
Figure O-2 Oven Schematic-Microwave cooking Condition
H.V. RECTIFIER
CAPACITOR
0.94µF
AC2200V
N.O.
N.O.
N.O.
COM.
MAGNETRON
POWER
TRANSFORMER
MONITOR SWITCH
GRILL HEATER (TOP)
BOTTOM HEATER
CONTROL UNIT
RY2: RPIMARY
INTERLOCK RELAY
RY6
THERMAL CUT-OUT
(OVEN)
TURNTABLE
MOTOR
A3
RY5
COM.
COM.
COM.
N.O.
A3
A5
RY4
RY3
H.V. RECTIFIER
CAPACITOR
0.94µF
AC2200V
N.O.
MAGNETRON
POWER
TRANSFORMER
MONITOR SWITCH
N.O.
N.O.
COM.
RY2: RPIMARY
INTERLOCK RELAY
RY6
RY5
GRILL HEATER (TOP)
BOTTOM HEATER
TURNTABLE
MOTOR
TTM
OL
OVEN LAMP
FM
FAN MOTOR
RY1
FUSE 20A
A1
LIVE
CONTROL UNIT
COM.
N.O.
A5
CM
D3
D1
B2
B1
EARTH
G-Y
THERMAL CUT-OUT
(OVEN)
TTM
OL
OVEN LAMP
FM
FAN MOTOR
RY1
CONVECTION
MOTOR
THERMISTOR
DOOR
SENSING
SWITCH
NEUTRAL
120V ~ 60Hz
BRN
NOTE:
CM
D3
FUSE 20A
A1
LIVE
BLU
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2.
:
OR CLOCK APPEAR ON DISPLAY.
CONVECTION
MOTOR
D1
B2
B1
EARTH
G-Y
120V ~ 60Hz
BRN
THERMAL
CUT-OUT
(MAG.)
THERMISTOR
DOOR
SENSING
SWITCH
NEUTRAL
BLU
R-820BK
R-820BW
Indicates components with potential above 250 V.
SECONDARY
INTERLOCK SWITCH
Figure O-1 Oven Schematic-OFF Condition
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. MICROWAVE POWER LEVEL PAD PRESSED ONCE(100%).
3. COOKING TIME PROGRAMMED.
4. START PAD TOUCHED.
R-820BK
R-820BW
MAGNETRON
H.V. RECTIFIER
CAPACITOR
0.94µF
AC2200V
MONITOR SWITCH
GRILL HEATER (TOP)
BOTTOM HEATER
COM.
COM.
TURNTABLE
MOTOR
COM.
TTM
N.O.
OL
OVEN LAMP
POWER
TRANSFORMER
N.O.
N.O.
RY4
RY3
RY6
RY5
A3
A5
FAN MOTOR
FM
RY1
CM
CONVECTION
MOTOR
THERMISTOR
D3
D1
B2
B1
DOOR
SENSING
SWITCH
THERMAL
CUT-OUT
(MAG.)
N.O.
COM.
RY2: RPIMARY
INTERLOCK RELAY
CONTROL UNIT
A1
FUSE 20A
Indicates components with potential above 250 V.
THERMAL CUT-OUT
(OVEN)
LIVE
BRN
NOTE:
EARTH
G-Y
NEUTRAL
BLU
120V ~ 60Hz
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. GRILL PAD TOUCHED.
3. NUMBER "1" PAD TOUCHED.
4. COOKING TIME PROGRAMMED.
5. START PAD TOUCHED.
SECONDARY
INTERLOCK SWITCH
Figure O-3a Oven Schematic-Grill cooking Condition (TOP AND BOTTOM HEATER mode)
MAGNETRON
SECONDARY
INTERLOCK SWITCH
Figure O-3b Oven Schematic-Grill cooking Condition (TOP HEATER mode)
10
H.V. RECTIFIER
CAPACITOR
0.94µF
AC2200V
MONITOR SWITCH
BOTTOM HEATER
GRILL HEATER (TOP)
RY4
COM.
TURNTABLE
MOTOR
COM.
TTM
POWER
TRANSFORMER
N.O.
RY3
COM.
N.O.
RY2: RPIMARY
INTERLOCK RELAY
RY6
OL
OVEN LAMP
FM
N.O.
A3
RY5
FAN MOTOR
CM
A5
RY1
D3
CONVECTION
MOTOR
D1
B2
THERMISTOR
DOOR
SENSING
SWITCH
B1
EARTH
THERMAL
CUT-OUT
(MAG.)
N.O.
COM.
CONTROL UNIT
A1
FUSE 20A
THERMAL CUT-OUT
(OVEN)
LIVE
BRN
BLU
G-Y
NEUTRAL
120V ~ 60Hz
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. GRILL PAD TOUCHED.
3. NUMBER "2" PAD TOUCHED.
4. COOKING TIME PROGRAMMED.
5. START PAD TOUCHED.
R-820BK
R-820BW
MAGNETRON
H.V. RECTIFIER
CAPACITOR
0.94µF
AC2200V
MONITOR SWITCH
GRILL HEATER (TOP)
BOTTOM HEATER
COM.
COM.
TURNTABLE
MOTOR
COM.
TTM
N.O.
OL
OVEN LAMP
POWER
TRANSFORMER
N.O.
N.O.
RY4
RY3
RY6
A3
RY5
A5
FAN MOTOR
FM
RY1
CM
CONVECTION
MOTOR
THERMISTOR
D3
D1
B2
DOOR
SENSING
SWITCH
B1
EARTH
THERMAL
CUT-OUT
(MAG.)
N.O.
COM.
RY2: RPIMARY
INTERLOCK RELAY
CONTROL UNIT
A1
FUSE 20A
THERMAL CUT-OUT
(OVEN)
LIVE
NEUTRAL
G-Y
BRN
BLU
120V ~ 60Hz
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. CONVECTION PAD TOUCHED.
3. NUMBER "1" PAD TOUCHED.
4. TEMPERATURE PAD TOUCHED.
5. COOKING TIME PROGRAMMED.
6. START PAD TOUCHED.
SECONDARY
INTERLOCK SWITCH
Figure O-4 Oven Schematic-Convection cooking Condition (Convection with preheat mode)
11
MAGNETRON
H.V. RECTIFIER
CAPACITOR
0.94µF
AC2200V
MONITOR SWITCH
BOTTOM HEATER
Figure O-5 Oven Schematic-Roast cooking Condition
GRILL HEATER (TOP)
RY4
COM.
TURNTABLE
MOTOR
COM.
TTM
SECONDARY
INTERLOCK SWITCH
POWER
TRANSFORMER
N.O.
RY3
COM.
RY6
OL
OVEN LAMP
FM
N.O.
A3
RY5
FAN MOTOR
CM
A5
RY1
D3
CONVECTION
MOTOR
D1
B2
THERMISTOR
DOOR
SENSING
SWITCH
N.O.
RY2: RPIMARY
INTERLOCK RELAY
CONTROL UNIT
B1
EARTH
THERMAL
CUT-OUT
(MAG.)
N.O.
COM.
THERMAL CUT-OUT
(OVEN)
A1
FUSE 20A
NOTE: The microwave relay (RY2) and the heater relay (RY3 or RY4) are not energized
simultaneously.
LIVE
G-Y
NEUTRAL
BRN
BLU
120V ~ 60Hz
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. ROAST PAD TOUCHED.
3. COOKING TIME PROGRAMMED.
4. START PAD TOUCHED.
R-820BK
R-820BW
DESCRIPTION AND FUNCTION OF COMPONENTS
DOOR OPEN MECHANISM
of the monitor switch contacts.
CAUTION: BEFORE REPLACING A BLOWN MONITOR
FUSE TEST THE DOOR SENSING SWITCH,
PRIMARY INTERLOCK RELAY (RY2), RELAY
(RY6), 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.
The door is opened by pushing the open button on the
control panel, refer to Figure D-1.
When the open button is pushed, the open button pushes up
the switch lever, and then the switch lever pushes up the
latch head. The latch heads are moved upward and released from latch hook. Now the door will open.
Latch
Heads Latch Hook
TURNTABLE MOTOR
Door
Sensing
Switch
Door
Switch
Lever
The turntable motor rotates the turntable located on the
bottom of the oven cavity, so that the food on the turntable
cook evenly during cooking. The turntable may turn in either
direction.
Monitor
Switch
Secondary
Interlock
Switch
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 food. It is then
exhausted through the exhausting air vents at the oven
cavity.
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 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.
MONITOR SWITCH
THERMAL CUT-OUT 125˚C (MAGNETRON)
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.
This thermal cut-out protects the magnetron against overheating. If the temperature goes up higher than 257˚F
(125˚C) because the fan motor is interrupted or the ventilation openings are blocked, the thermal cut-out will open and
line voltages to the high voltage transformer will be cut off
and the operation of the magnetron will be stopped. The
thermal cut-out will not resume.
Functions:
1. When the door is opened, the monitor switch contacts
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
THERMAL CUT-OUT 170˚C (OVEN)
The thermal cut-out located on the top of the oven cavity is
designed to prevent damage to the oven if the food in the
oven catch fire due to over heating produced by improper
setting of the cooking time or failure of control unit. Under the
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
338˚F(170˚C) causing the oven to shut down. The thermal
cut-out will close in at 311˚F(155˚C).
TOP HEATERS
The top heaters are located on the top of the oven cavity
assembly. The top heaters send out heat to grill foods.
12
R-820BK
R-820BW
BOTTOM HEATER
Most of this hot air is reheated by the top heaters and the
bottom heater and passes through the convection passage
and enters the inside of the oven cavity again, in a continuing cycle.
In this way, the hot air circulates inside the oven cavity to
raise its temperature and, at the same time, comes into
contact with the food being cooked.
When the temperature inside the oven cavity reaches the
selected temperature, the top heaters and the bottom heater
are de-energized. When the temperature inside the oven
cavity drops below the selected temperature, the top heaters and the bottom heater are energized again. In this way,
the inside of the oven cavity is maintained at approximately
the selected temperature.
When the convection time reaches 0, the top heaters and
the bottom heater are de-energized and the convection fan
stops operating and the oven shuts off.
The bottom heater is located on the floor of the oven cavity
assembly. The bottom heater sends out heat to grill foods.
CONVECTION COOKING SYSTEM
This oven is designed with a hot air heating system where
food is not directly heated by the top heaters and the bottom
heater, but is heated by forced circulation of the hot air
produced by the top heaters and the bottom heater.
The air heated by the top heaters and the bottom heater is
circulated through the convection passage provided on the
outer casing of the oven cavity by means of the convection
fan which is driven by the convection motor. It then enters
the inside of the oven through the vent holes provided on the
left side of the oven. Next, the hot air heats the food on the
turntable and leaves the oven cavity through the vent in the
center of the oven cavity rear wall.
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 (RY6),
primary interlock relay (RY2), door sensing switch and secondary interlock switch before replacing the
monitor fuse. If monitor fuse is replaced, the monitor switch must also be replaced. Use part FFSBA021WRK0 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 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.
13
R-820BK
R-820BW
CK = Check / RE = Replace
POSSIBLE CASE
AND
DEFECTIVE PARTS
CONDITION
PROBLEM
A B C D E E F F G H I
Monitor fuse blows when power
cord is plugged into wall outlet.
Monitor fuse blows when the door
is opened.
Oven lamp does not light when
door is opened. (Display operates.)
OFF
CONDITION
Home fuse blows when power cord
is plugged into wall outlet.
"SHARP SIMPLY ..... PRESS CLOCK"
does not appear in display when
power cord is plugged into wall outlet.
Display does not operate properly
when STOP/CLEAR pad is pressed.
Oven does not start when the
START pad is pressed. (Display
operates.)
Oven lamp does not light. (Turntable
motor operates.)
COOKING
CONDITION
(COMMON MODE)
Fan motor does not operate. (Oven
lamp lights.)
Turntable motor does not operate.
(Oven lamp lights.)
Oven or electrical parts does not
stop when cooking time is 0 or
STOP/CLEAR pad is pressed.
Oven goes into cook cycle but shuts
down before end of cooking cycle.
Oven seems to be operating but little
or no heat is produced in oven load.
MICROWAVE
COOKING
CONDITION
Oven does not operate properly
during variable cooking condition
except 100% cooking condition.
Function of COMPU DEFROST does
not operate properly.
GRILL
COOKING
CONDITION
ROAST
COOKING
CONDITION
Top heaters do not operate.
Bottom heater does not operate.
Oven seems to be operating but
little or no heat is produced in oven
load. (Microwave power does not
seem to be generated properly.)
Top heaters do not operate.
Bottom heater does not operate.
CONVECTION
COOKING
CONDITION
I J L M N N N N N N O P RERERERERE CK CK CK
MAGNETRON
POWER TRANSFORMER
H.V. RECTIFIER ASSEMBLY
HIGH VOLTAGE CAPACITOR
THERMAL CUT-OUT 170˚C
THERMAL CUT-OUT 125˚C
SECONDARY INTERLOCK SWITCH
PRIMARY INTERLOCK SYSTEM
MONITOR SWITCH
MONITOR FUSE
TOP HEATERS
BOTTOM HEATER
THERMISTOR
TOUCH CONTROL PANEL
KEY UNIT
RELAY RY1
RELAY RY2
RELAY RY3
RELAY RY4
RELAY RY5
RELAY RY6
COMPU DEFROST
FOIL PATTURN ON P.W.B.
CONVECTION MOTOR
FAN MOTOR
TURNTABLE MOTOR
POWER SUPPLY CORD
OVEN LAMP OR SOCKET
SHORTED WIRE HARNESS
OPENED WIRE HARNESS
MIS-ADJUSTMENT OF SWITCHES
TEST PROCEDURE
Temperature is lower or higher than
preset.
Convection motor does not operate.
Oven stops after 4 minutes 15 sec..
14
R-820BK
R-820BW
TEST PROCEDURES
PROCEDURE
LETTER
A
COMPONENT TEST
MAGNETRON ASSEMBLY TEST
1.
2.
3.
4.
5.
6.
7.
8.
9.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
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.
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.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
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:
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 10(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 22
to 43˚F(12.2 to 23.9˚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.
2.
3.
4.
5.
6.
7.
8.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
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 73 ohms; the resistance of the filament coil should be less than 1 ohm.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
15
R-820BK
R-820BW
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
(HIGH VOLTAGES ARE PRESENT AT THE HIGH VOLTAGE TERMINAL, SO DO NOT ATTEMPT TO
MEASURE THE FILAMENT AND HIGH VOLTAGE.)
C
HIGH VOLTAGE RECTIFIER TEST
1.
2.
3.
4.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
Isolate the rectifier from the circuit. Using the highest ohm scale of the meter, read the resistance
across the terminals and observe, reverse the leads to the rectifier terminals and observe meter
reading. If a short is indicated in both directions, or if an infinite resistance is read in both directions,
the rectifier is probably defective and should be replaced.
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.
NOTE: Be sure to use an ohmmeter that will supply a forward bias voltage of more than 6.3 volts.
D
HIGH VOLTAGE CAPACITOR TEST
1.
2.
3.
4.
5.
6.
7.
8.
E
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
If the capacitor is open, no high voltage will be available to the magnetron. Disconnect input leads
and check for a short or open between the terminals using an ohmmeter.
Checking with a high ohm scale, if the high voltage capacitor is normal, the meter will indicate
continuity for a short time and should indicate an open circuit once the capacitor is charged. If the
above is not the case, check the capacitor with an ohmmeter to see if it is shorted between either of
the terminals and case. If it is shorted, replace the capacitor.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
THERMAL CUT-OUT TEST 170˚C (OVEN)
1.
2.
3.
4.
5.
6.
7.
8.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
A continuity check across the thermal cut-out terminals should indicate a closed circuit unless the
temperature of the thermal cut-out reaches approximately 338˚F(170˚C). The thermal cut-out resets
automatically below approximately 311˚F(155˚C).
An open thermal cut-out indicates overheating of the oven, check inside of oven cavity for improper
setting of cooking time or operation of control unit. Check for restricted air flow through the vent holes
of the oven cavity, especially the cooling fan and air guide.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
THERMAL CUT-OUT TEST 125˚C (MAGNETRON)
1.
2.
3.
4.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
A continuity check across the thermal cut-out terminals should indicate a closed circuit. If the
temperature of the magnetron reaches approximately 257˚F(125˚C), the thermal cut-out opens. An
open thermal cut-out indicates overheating of the magnetron, exchange the thermal cut-out. Check
for restricted air flow to the magnetron, especially the cooling fan air guide.
16
R-820BK
R-820BW
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
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.
CAUTION: IF THE THERMAL CUT-OUT INDICATES AN OPEN CIRCUIT AT ROOM TEMPERATURE,
REPLACE THERMAL CUT-OUT.
F
SECONDARY INTERLOCK SWITCH TEST
1.
2.
3.
4.
5.
6.
7.
8.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO) terminal
of the switch. The meter should indicate an open circuit with the door open and a closed circuit with
the door closed. If improper operation is indicated, replace the secondary interlock switch.
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
PRIMARY INTERLOCK SYSTEM TEST
DOOR SENSING SWITCH
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. Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO) terminal
of the switch. The meter should indicate an open circuit with the door open and a closed circuit with
the door closed. If improper operation is indicated, replace the door sensing switch.
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.
NOTE: If the door sensing switch contacts fail in the open position and the door is closed, the cooling
fan, turntable and oven light will be activated by relay(RY6).
PRIMARY INTERLOCK RELAY (RY2)
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 two (2) wire leads from the male tab terminals of the Primary Interlock Relay. Check the
state of the relay contacts using a ohmmeter. The relay contacts should be open. If the relay contacts
are closed, replace the circuit board entirely or the relay itself.
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.
G
MONITOR SWITCH TEST
1.
2.
3.
4.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
Before performing this test, make sure that the secondary interlock switch and the primary interlock
relay are operating properly, according to the above Switch Test Procedure. Disconnect the wire lead
from the monitor switch (COM) terminal. Check the monitor switch operation by using the ohmmeter
as follows. When the door is open, the meter should indicate a closed circuit. When the monitor switch
actuator is pushed by a screw driver through the lower latch hole on the front plate of the oven cavity
17
R-820BK
R-820BW
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
5.
6.
7.
8.
with the door opened (in this condition the plunger of the monitor switch is pushed in), the meter should
indicate an open circuit. If improper operation is indicated, the switch may be defective. After testing
the monitor switch, reconnect the wire lead to the monitor switch (COM) terminal and check the
continuity of the monitor circuit.
Reconnect all leads removed from components
RED
during testing.
WHT
SCREW
DRIVER
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the
outer case is installed.
Run the oven and check all functions.
MONITOR
SWITCH
OHMMETER
H
BLOWN MONITOR FUSE TEST
1.
2.
3.
4.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
If the monitor fuse is blown when the door is opened, check the primary interlock relay, secondary
interlock switch and monitor switch according to the "TEST PROCEDURE" for those switches before
replacing the blown monitor fuse.
CAUTION: BEFORE REPLACING A BLOWN MONITOR FUSE, TEST THE PRIMARY INTERLOCK
RELAY, SECONDARY INTERLOCK SWITCH, DOOR SENSING SWITCH AND MONITOR
SWITCH FOR PROPER OPERATION.
If the monitor fuse is blown by improper switch operation, the monitor fuse and monitor switch must
be replaced with "monitor fuse and monitor switch assembly" part number FFS-BA021WRK0, even
if the monitor switch operates normally. The monitor fuse and monitor switch assembly is comprised
of a 20 ampere fuse and switch.
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.
I
TOP HEATERS AND BOTTOM HEATER TEST
1.
2.
3.
4.
5.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
Make sure the heater is cooled completely.
Resistance of heater.
Disconnect the wire leads to the heater to be tested. Using ohmmeter with low resistance range.
Check the resistance across the terminals of the heater as described in the following table.
Table: Resistance of heater
Parts name
Resistance
Top heaters
Approximately 7.2 Ω x 2 = 14.4 Ω
Bottom heater
Approximately 28.8 Ω
6. Insulation resistance.
Disconnect the wire leads to the heater to be tested. Check the insulation resistance between the
heater terminal and cavity using a 500V - 100MΩ insulation tester. The insulation resistance should
be more than 10 MΩ in the cold start.
7. If the results of above test 5 and/or 6 are out of above specifications, the heater is probably faulty and
should be replaced.
8. Reconnect all leads removed from components during testing.
9. Reinstall the outer case (cabinet).
18
R-820BK
R-820BW
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
10.Reconnect the power supply cord after the outer case is installed.
11.Run the oven and check all functions.
J
K
THERMISTOR TEST
1.
2.
3.
4.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
Disconnect connector-D from the control unit. Measure the resistance of the thermistor with an
ohmmeter. Connect the ohmmeter leads to Pin No’s D1 and D3.
Room Temperature
Resistance
68˚F(20˚C) - 86˚F(30˚C)
Approx. 293kΩ - 184KΩ
5.
6.
7.
8.
9.
If the meter does not indicate above resistance, replace the thermistor
Reconnect all leads removed from components during testing.
Reinstall the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
CHECKING TEMPERATURE IN THE CONVECTION MODE
The following test procedure should be carried out with the microwave oven is a fully assembled
condition (outer case fitted).
It is difficult to measure the exact temperature in the convection oven. An accurate thermocouple type
temperature tester must be used. A low priced bi-metal type thermometer is not reliable or accurate.
The temperature should be checked with outer case cabinet installed, approx. 5 minutes after preheat
temperature is reached (audible signal sounds four times). The temperature experienced may be
approx. 30˚F more or less than indicated on the display, however, in most cases the food cooking results
will be satisfactory.
Difference in power supply voltage will also affect the oven temperature. The Household power supply
voltage may sometimes become lower than the rated voltage (120 V) and cause under-cooking. If the
power supply voltage is 10% lower than the rated voltage, longer cooking time is required by 10% to 20%.
L
TOUCH CONTROL PANEL ASSEMBLY TEST
The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore,
unlike conventional microwave ovens, proper maintenance cannot be performed with only a voltmeter
and ohmmeter.
In this service manual, the touch control panel assembly is divided into two units, Control Unit and Key
Unit, and also the Control Unit is divided into two units, CPU Unit and Power Unit, and troubleshooting
by unit replacement is described according to the symptoms indicated.
Before testing,
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 these leads remain isolated from other components and oven chassis by using
insulation tape.
6) After that procedure, re-connect the power supply cord.
1. Key Unit.
NOTE ;
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) Check key unit ribbon connection before replacement.
5) Reconnect all leads removed from components during testing.
19
R-820BK
R-820BW
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
6) Re-install the outer case (cabinet).
7) Reconnect the power supply cord after the outer case is installed.
8) Run the oven and check all functions.
The following symptoms indicate a defective key unit.
a) When touching the pads, a certain pad produces no signal at all.
b) When touching a number pad, two figures or more are displayed.
c) When touching the pads, sometimes a pad produces no signal.
If the key unit is defective.
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) Replace the key unit.
5) Reconnect all leads removed from components during testing.
6) Re-install the outer case (cabinet).
7) Reconnect the power supply cord after the outer case is installed.
8) Run the oven and check all functions.
2. Control Unit.
The following symptoms indicate a defective control unit. Before replacing the control unit, perform
the Key unit test (Procedure M) to determine if control unit is faulty.
2-1 In connection with pads.
a) When touching the pads, a certain group of pads do not produce a signal.
b) When touching the pads, no pads produce a signal.
2-2 In connection with indicators
a) At a certain digit, all or some segments do not light up.
b) At a certain digit, brightness is low.
c) Only one indicator does not light.
d) The corresponding segments of all digits do not light up; or they continue to light up.
e) Wrong figure appears.
f) A certain group of indicators do not light up.
g) The figure of all digits flicker.
2-3 Other possible problems caused by defective control unit.
a) Buzzer does not sound or continues to sound.
b) Clock does not operate properly.
c) Cooking is not possible.
d) Proper temperature measurement is not obtained.
When 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) Re-install the outer case (cabinet).
6) Reconnect the power supply cord after the outer case is installed.
7) Run the oven and check all functions.
M
KEY UNIT TEST
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. If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon cable
is making good contact, verify that the door sensing switch (stop switch) operates properly; that is the
contacts are closed when the door is closed and open when the door is open. If the door sensing
switch (stop switch) is good, disconnect the flat ribbon cable that connects the key unit to the control
unit and make sure the door sensing switch is closed (either close the door or short the door sensing
switch connecter). Use the Key unit matrix indicated on the control panel schematic and place a
jumper wire between the pins that correspond to the STOP/CLEAR pad making momentary contact.
20
R-820BK
R-820BW
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
If the control unit responds by clearing with a beep the key unit is faulty and must be replaced. If the
control unit does not respond, it is faulty and must be replaced. If a specific pad does not respond,
the above method may be used (after clearing the control unit) to determine if the control unit or key
pad is at fault.
5. Reconnect all leads removed from components during testing.
6. Re-install the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
N
G6
G5
G4
G3
G2
G1
CUSTOM
HELP
STOP
CLEAR
G9
G7
5
4
3
2
1
GRILL
BAKE
G12 G11 G10
G8
0
9
8
7
6
PIZZA
COOK
GRILL
CONVEC
START POWER
ROAST REHEAT ROAST
TOUCH ON LEVEL
CLOCK MINUTE
PLUS
DEFROST KITCHEN POPCORN
TIMER
RELAY TEST
1.
2.
3.
4.
5.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
Disconnect the leads to the primary of the power transformer.
Ensure that these leads remain isolated from other components and oven chassis by using insulation
tape.
6. After that procedure, re-connect the power supply cord.
7. Remove the outer case and check voltage between Pin No. 1 of the 3 pin connector (A) and the
common terminal of the relay RY6 on the control unit with an A.C. voltmeter.
The meter should indicate 120 volts, if not check oven circuit.
Shut off, Cook and Heater Relay Test
These relays are operated by D.C. voltage
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation, grill
cooking operation, or convection cooking operation.
DC. voltage indicated ............. Defective relay.
DC. voltage not indicated ........ Check diode which is connected to the relay coil. If diode is good, control
unit is defective.
RELAY SYMBOL
RY1
RY2
RY3
RY4
RY5
RY6
OPERATIONAL VOLTAGE
Approx. 24.0V D.C.
Approx. 24.0V D.C.
Approx. 24.0V D.C.
Approx. 24.0V D.C.
Approx. 24.0V D.C.
Approx. 24.0V D.C.
CONNECTED COMPONENTS
Convection motor
Power transformer
Grill heaters (Top)
Bottom heater
Fan motor
Oven lamp / Turntable motor
8. Disconnect the power supply cord, and then remove outer case.
9. Open the door and block it open.
10.Discharge high voltage capacitor.
11.Reconnect all leads removed from components during testing.
12.Re-install the outer case (cabinet).
13.Reconnect the power supply cord after the outer case is installed.
14.Run the oven and check all functions.
21
R-820BK
R-820BW
TEST PROCEDURES
PROCEDURE
LETTER
O
COMPONENT TEST
COMPU DEFROST TEST
WARNING : The oven should be fully assembled before following procedure.
(1) Place one cup of water in the center of the turntable tray in the oven cavity.
(2) Close the door, touch the " Compu Defrost " pad once and touch the Number pad "1", and touch the
Number pad 5. And then touch the "START" pad.
(3) The oven is in Compu Defrost cooking condition.
(4) The oven will operate as follows
WEIGHT
0.5lb
1ST STAGE
LEVEL TIME
70%
50sec.
2ND STAGE
LEVEL TIME
0%
1min.
3RD STAGE
LEVEL TIME
50%
35sec.
4TH STAGE
LEVEL TIME
30%
45sec.
(5) If improper operation is indicated, the control unit is probably defective and should be checked.
P
FOIL PATTERN ON THE PRINTED WIRING BOARD TEST
To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on
the PWB, this foil pattern acts as a fuse.
1. Foil pattern check and repairs.
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) Follow the troubleshooting guide given below for repair.
STEPS
OCCURRENCE
CAUSE OR CORRECTION
1
Only pattern at "a" is broken.
*Insert jumper wire J1 and solder.
2
Pattern at "a" and "b" are broken.
*Insert the coil RCILF2003YAZZ between "c" and "d".
c
VRS1
a
5
(J1)
5) Make a visual inspection of the varistor.
Check for burned damage and examine
the transformer with a tester for the
presence of layer short-circuit (check
the primary coil resistance which is
approximately 218Ω ± 10%). If any
abnormal condition is detected, replace
the defective parts.
FAN
b
d
1
AC
CN - A
6) Reconnect all leads removed from components during testing.
7) Re-install the outer case (cabinet).
8) Reconnect the power supply cord after the outer case is installed.
9) Run the oven and check all functions.
2. Follow the troubleshooting guide given below, if indicator does not light up after above check and
repairs are finished.
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 these leads remain isolated from other components and oven chassis by using
insulation tape.
6) After that procedure, re-connect the power supply cord.
7) Follow the troubleshooting guide given below for repair.
22
R-820BK
R-820BW
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
STEPS
8)
9)
10)
11)
12)
13)
14)
OCCURRENCE
CAUSE OR CORRECTION
1
The rated AC voltage is not present between
Pin No. 1 of the 3-pin connector (A) and the
common terminal of the relay RY6.
Check supply voltage and oven power cord.
2
The rated AC voltage is present at primary
side of low voltage transformer.
Low voltage transformer or secondary circuit defective.
Check and repair.
Disconnect the power supply cord, and then remove outer case.
Open the door and block it open.
Discharge high voltage capacitor.
Reconnect all leads removed from components during testing.
Re-install the outer case (cabinet).
Reconnect the power supply cord after the outer case is installed.
Run the oven and check all functions.
23
R-820BK
R-820BW
TOUCH CONTROL PANEL ASSEMBLY
OUTLINE OF TOUCH CONTROL PANEL
The touch control section consists of the following units as
shown in the touch control panel circuit.
4) ACL
A circuit to generate a signal which resets the LSI to the
initial state when power is supplied.
(1) Key Unit
(2) Control Unit (The Control unit consists of Power unit and
CPU unit.)
5) Buzzer Circuit
The buzzer is responsive to signals from the LSI to emit
audible sounds (key touch sound and completion sound).
The principal functions of these units and signals communicated among them are explained below.
6) Door Sensing Switch (Stop Switch)
A switch to "tell" the LSI if the door is open or closed.
Key Unit
The key unit is composed of a matrix, signals generated in
the LSI are sent to the key unit from P40, P41, P72, P73 P74,
P75, P76 and P77.
When a key pad is touched, a signal is completed through
the key unit and passed back to the LSI through P44 - P47
to perform the function that was requested.
7) Relay Circuit
To drive the magnetron, grill heaters, bottom heater,
convection motor, fan motor, turntable motor and light
the oven lamp.
8) Back Light Circuit
A circuit to drive the back light (Light emitting diodes LD1
- LD10).
Control Unit
Control unit consists of LSI, power source circuit, synchronizing signal circuit, ACL circuit, buzzer circuit, relay circuit,
temperature measurement circuit, indicator circuit and back
light circuit.
9) Indicator Circuit
This circuit consists of 2line, 7-digits, 45-segments and
5-common electrodes using a Liquid Crystal Display.
1) LSI
This LSI controls the temperature measurement signal,
key strobe signal, relay driving signal for oven function
and indicator signal.
10)Temperature Measurement Circuit : (OVEN THERMISTOR)
The temperature in the oven cavity is sensed by the
thermistor. The variation of resistance according to
sensed temperature is detected by the temperature
measurement circuit and the result applied to LSI. The
LSI uses this information to control the relay and display
units.
2) Power Source Circuit
This circuit generates voltage necessary in the control
unit.
Symbol
VC
Voltage
-5.2V
Application
LSI(IC1)
3) Synchronizing Signal Circuit
The power source synchronizing signal is available in
order to compose a basic standard time in the clock
circuit. It accompanies a very small error because it
works on commercial frequency.
24
R-820BK
R-820BW
DESCRIPTION OF LSI
LSI(IZA888DR)
The I/O signal of the LSI(IZA888DR) are detailed in the following table.
Pin No.
1
2
Signal
C1
VL1
I/O
IN
IN
AN7-AN5
IN
6
7
AN4
AN3
IN
IN
Terminal not used.
Temperature measurement input: OVEN THERMISTOR.
By inputting DC voltage corresponding to the temperature detected by the thermistor,
this input is converted into temperature by the A/D converter built into the LSI.
8
AN2
IN
Input signal which communicates the door open/close information to LSI.
3-5
Description
Terminal not used.
Power source voltage input terminal.
Standard voltage for LCD.
Heating constant compensation terminal.
Door closed; "H" level signal.
Door opened; "L" level signal.
9-10
AN1-AN0
IN
11
P57
OUT
12
P56
OUT
13
P55
OUT
Timing signal output terminal for temperature measurement(OVEN THERMISTOR).
"H" level (GND) : Thermistor OPEN timing.
"L" level (-5V) : Temperature measuring timing. (Convection cooking)
P54-P50
P47
IN/OUT
IN
Terminal not used.
Signal coming from touch key.
When any one of G12 line keys on key matrix is touched, a corresponding signal from
P40, P41, P72, P73, P74, P75, P76 and P77 will be input into P47. When no key is
touched, the signal is held at "L" level.
20
P46
IN
Signal similar to P47.
When any one of G11 line keys on key matrix is touched, a corresponding signal will
be input into P46.
21
P45
IN
Signal similar to P47.
When any one of G10 line keys on key matrix is touched, a corresponding signal will
be input into P45.
22
P44
IN
Signal similar to P47.
When any one of G9 line keys on key matrix is touched, a corresponding signal will
be input into P44.
23
INT1
IN
Terminal not used.
24
INT0
IN
Signal to synchronized LSI with commercial power source frequency(60Hz).
14-18
19
Terminal not used.
Timing signal output terminal for temperature measurement(OVEN THERMISTOR).
"H" level (GND) : Thermistor OPEN timing.
"L" level (-5V) : Temperature measuring timing. (Convection cooking)
Signal to sound buzzer.
0.1 sec
A: key touch sound.
A
B: Completion sound.
2.0 sec
C: When the temperature of the oven cavB
ity reaches the preset temperature in
1.0 sec
1.0 sec
the preheating mode, or when the
H: GND
C
preheating hold time (30 minutes) is
L
elapsed.
H : GND
This is basic timing for time processing of LSI.
L (-5V)
16.7 msec.
25
P41
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P44 - P47 terminal while
one of G8 line key on matrix is touched.
25
R-820BK
R-820BW
Pin No.
Signal
I/O
Description
26
P40
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P44 - P47 terminal while
one of G7 line key on matrix is touched.
27
P77
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P44 - P47 terminal while
one of G6 line key on matrix is touched.
28
P76
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P44 - P47 terminal while
one of G5 line key on matrix is touched.
29
P75
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P44 - P47 terminal while
one of G4 line key on matrix is touched.
30
P74
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P44 - P47 terminal while
one of G3 line key on matrix is touched.
31
P73
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P44 - P47 terminal while
one of G2 line key on matrix is touched.
32
P72
OUT
Key strobe signal.
Signal applied to touch-key section. A pulse signal is input to P44 - P47 terminal while
one of G1 line key on matrix is touched.
33
P71
OUT
Oven lamp and turntable motor driving signal(Square Waveform : 60Hz).
To turn on and off shut-off relay (RY6). The
square waveform voltage is delivered to
the relay (RY6) driving circuit.
16.7 msec.
H
L
During cooking
34
P70
IN
Connected to VC.
35
RESET
IN
Auto clear terminal.
Signal is input to reset the LSI to the initial state when power is applied. Temporarily
set to "L" level the moment power is applied, at this time the LSI is reset. Thereafter
set at "H" level.
36
P81
OUT
Magnetron high-voltage circuit driving signal.
To turn on and off the cook relay
(RY2). In P-HI operation, the signals hold "L" level during microwave
cooking and "H" level while not cooking. In other cooking modes (P-90,
P-80, P-70, P-60, P-50, P-40, P-30,
P-20, P-10, P-0) the signal turns to
"H" level and "L" level in repetition
according to the power level.
37
P80
OUT
Grill heaters (TOP HEATER) driving signal.
To turn on and off the grill heaters relay
(RY3). "L" level during grill (TOP GRILL,
TOP AND BOTTOM) cooking, Convection cooking or Roast cooking, "H"
level otherwise.
The heater relay turns on and off within
a 48 second time base in accordance
with the special program in LSI.
38
XIN
IN
VARI
ON TIME OFF TIME
P-HI(100% power)
32 sec.
0 sec.
P-90(approx. 90% power) 30 sec.
2 sec.
P-80(approx. 80% power) 26 sec.
6 sec.
P-70(approx. 70% power) 24 sec.
8 sec.
P-60(approx. 60% power) 22 sec.
10 sec.
P-50(approx. 50% power) 18 sec.
14 sec.
P-40(approx. 40% power) 16 sec.
16 sec.
P-30(approx. 30% power) 12 sec.
20 sec.
P-20(approx. 20% power) 8 sec.
24 sec.
P-10(approx. 10% power) 6 sec.
26 sec.
P-0(0% power)
0 sec.
32 sec.
Power output
100 %
90 %
80 %
70 %
60 %
50 %
40 %
30 %
20 %
10 %
ON time
48 sec.
44 sec.
40 sec.
36 sec.
32 sec.
26 sec.
22 sec.
16 sec.
12 sec.
8 sec.
OFF time
0 sec.
4 sec.
8 sec.
12 sec.
16 sec.
22 sec.
26 sec.
32 sec.
36 sec.
40 sec.
Internal clock oscillation frequency input setting.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit with
respect to XIN terminal.
26
R-820BK
R-820BW
Pin No.
Signal
I/O
39
XOUT
OUT
40
VSS
IN
Power source voltage: -5V.
VC voltage of power source circuit input.
41
P27
OUT
Bottom heater driving signal.
To turn on and off the bottom relay (RY4).
"L" level during grill (TOP AND BOTTOM)
cooking, Convection cooking or Roast
cooking, "H" level otherwise.
The heater relay turns on and off within a
48 second time base in accordance with
the special program in LSI.
42
P26
OUT
Convection motor driving signal.
To turn on and off shut-off relay(RY1). "L"
level during CONVECTION; "H" level otherwise. (Relay RY1 does not turn on at
preheating mode.)
43
P25
OUT
Description
Internal clock oscillation frequency control output.
Output to control oscillation input of XOUT.
Fan motor driving signal.
To turn on and off the fan motor relay RY5. "L"
level during cooking, or for 5 minutes after grill
cooking or for a while after convection or roust
cooking. "H" level otherwise.
Power output
100 %
90 %
80 %
70 %
60 %
50 %
40 %
30 %
20 %
10 %
ON
ON time
48 sec.
44 sec.
40 sec.
36 sec.
32 sec.
26 sec.
22 sec.
16 sec.
12 sec.
8 sec.
During
cooking
(Convection)
H. GND
OFF
L
OFF
ON
OFF time
0 sec.
4 sec.
8 sec.
12 sec.
16 sec.
22 sec.
26 sec.
32 sec.
36 sec.
40 sec.
H. GND
L
For 5 minutes after grill, or for a
while after convection or roust.
44
P24
OUT
Terminal not used.
45
P23
OUT
Common data signal: COM5.
Connected to LCD (Pin No. 37)
46-48
P22-P20
OUT
Segment data signal.
Connected to LCD. No connection in LCD.
49-50
P17-P16
OUT
Segment data signal.
Connecte 0d to LCD. No connection in LCD.
51-80
SEG39-SEG10
OUT
Segment data signal.
Connected to LCD.
The relation between signals are as follows:
LSI signal (Pin No.) LCD (Pin No.) LSI signal (Pin No.) LCD (Pin No.)
SEG 0 (90) ............... SEG45 (51)
SEG23 (67) ............ SEG17 (17)
SEG 1 (89) ............... SEG44 (50)
SEG24 (66) ............ SEG16 (16)
SEG 2 (88) ............... SEG43 (49)
SEG25 (65) ............ SEG15 (15)
SEG 3 (87) ............... SEG42 (48)
SEG25 (65) ............ SEG15 (32)
SEG 4 (86) ............... SEG41 (47)
SEG26 (64) ............ SEG14 (14)
SEG 5 (85) ............... SEG40 (46)
SEG27 (63) ............ SEG13 (13)
SEG 6 (84) ............... SEG39 (45)
SEG28 (62) ............ SEG12 (12)
SEG 7 (83) ............... SEG38 (44)
SEG29 (61) ............ SEG11 (11)
SEG 8 (82) ............... SEG37 (43)
SEG30 (60) ............ SEG10 (10)
SEG 9 (81) ............... SEG31 (31)
SEG31 (59) .............. SEG 9 ( 9)
SEG10 (80) .............. SEG30 (30)
SEG32 (58) .............. SEG 8 ( 8)
SEG11 (79) .............. SEG29 (29)
SEG33 (57) .............. SEG 7 ( 7)
SEG12 (78) .............. SEG28 (28)
SEG34 (56) .............. SEG 6 ( 6)
SEG13 (77) .............. SEG27 (27)
SEG35 (55) .............. SEG 5 ( 5)
SEG14 (76) .............. SEG26 (26)
SEG36 (54) .............. SEG 4 ( 4)
SEG15 (75) .............. SEG25 (25)
SEG37 (53) .............. SEG 3 ( 3)
SEG16 (74) .............. SEG24 (24)
SEG38 (52) .............. SEG 2 ( 2)
SEG17 (73) .............. SEG23 (23)
SEG39 (51) .............. SEG 1 ( 1)
SEG18 (72) .............. SEG22 (22)
P16 (50) ................. SEG32 (38)
SEG19 (71) .............. SEG21 (21)
P17 (49) ................. SEG33 (39)
SEG20 (70) .............. SEG20 (20)
P20 (48) ................. SEG34 (40)
SEG21 (69) .............. SEG19 (19)
P21 (47) ................. SEG35 (41)
SEG22 (68) .............. SEG18 (18)
P22 (46) ................. SEG36 (42)
27
R-820BK
R-820BW
Pin No.
Signal
I/O
81
SEG9
OUT
Segment data signal.
Connected to LCD. No connection in LCD.
SEG8-SEG0
OUT
Segment data signal.
Connected to LCD. Signal is similar to SEG39.
91
VCC
IN
Connected to GND.
92
VREF
IN
Connected to GND.
93
AVSS
IN
Connected to VC.
94
COM3
OUT
Common data signal: COM4.
Connected to LCD (Pin No. 36).
95
COM2
OUT
Common data signal: COM3.
Connected to LCD (Pin No. 35).
96
COM1
OUT
Common data signal: COM2.
Connected to LCD (Pin No. 34).
97
COM0
OUT
Common data signal: COM1.
Connected to LCD (Pin No. 33).
VL3-VL2
IN
Power source voltage input terminal.
Standard voltage for LCD.
C2
IN
Terminal not used.
82-90
98-99
100
Description
28
R-820BK
R-820BW
SERVICING
1. Precautions for Handling Electronic Components
5) Re-connect the power supply cord after the outer case is
installed.
6) Run the oven and check all functions.
This unit uses CMOS LSI in the integral part of the circuits.
When handling these parts, the following precautions should
be strictly followed. CMOS LSI have extremely high
impedance at its input and output terminals. For this reason,
it is easily influenced by the surrounding high voltage power
source, static electricity charge in clothes, etc., and
sometimes it is not fully protected by the built-in protection
circuit.
In order to protect CMOS LSI.
1) When storing and transporting, thoroughly wrap them in
aluminium foil. Also wrap PW boards containing them in
aluminium foil.
2) When soldering, ground the technician as shown in the
figure and use grounded soldering iron and work table.
A. On some models, the power supply cord between the
touch control panel and the oven itself is so short that the
two can't be separated.
For those models, check and repair all the controls
(sensor-related ones included) of the touch control panel
while keeping it connected to the oven.
B. On some models, the power supply cord between the
touch control panel and the oven proper is long enough
that they may be separated from each other. For those
models, therefore, it is possible to check and repair the
controls of the touch control panel while keeping it apart
from the oven proper; in this case you must short both
ends of the door sensing switch (on PWB) of the touch
control panel with a jumper, which brings about an
operational state that is equivalent to the oven door being
closed. As for the sensor-related controls of the touch
control panel, checking them is possible if the dummy
resistor(s) with resistance equal to that of the controls are
used.
approx. 1M ohm
2. Shapes of Electronic Components
E
C
(2) Servicing the touch control panel with power
supply from an external power source:
B
Transistor
2SB1238
E
CB
Disconnect the touch control panel completely from the
oven proper, and short both ends of the door sensing
switch (on PWB) of the touch control panel, which brings
about an operational state that is equivalent to the oven
door being closed. Connect an external power source to
the power input terminal of the touch control panel, then
it is possible to check and repair the controls of the touch
control panel; it is also possible to check the sensorrelated controls of the touch control panel by using the
dummy resistor(s).
Transistor
DTD143ES
3. Servicing of Touch Control Panel
We describe the procedures to permit servicing of the touch
control panel of the microwave oven and the precautions
you must take when doing so.
To perform the servicing, power to the touch control panel
is available either from the power line of the oven itself or
from an external power source.
(1) Servicing the touch control panel with power
supply of the oven :
CAUTION:
THE HIGH VOLTAGE TRANSFORMER OF THE
MICROWAVE OVEN IS STILL LIVE DURING SERVICING AND PRESENTS A HAZARD .
T herefore, before checking the performance of the touch
4. Servicing Tools
Tools required to service the touch control panel assembly.
1) Soldering iron: 30W
(It is recommended to use a soldering iron with a
grounding terminal.)
2) Oscilloscope: Single beam, frequency range: DC 10MHz type or more advanced model.
3) Others: Hand tools
control panel,
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 these leads remain isolated from other
components and oven chassis by using insulation tape.
6) After that procedure, re-connect the power supply cord.
After checking the performance of the touch control panel,
1) Disconnect the power supply cord.
2) Open the door and block it open.
3) Re-connect the leads to the primary of the power transformer.
4) Re-install the outer case (cabinet).
5. Other Precautions
1) Before turning on the power source of the control unit,
remove the aluminium foil applied for preventing static
electricity.
2) Connect the connector of the key unit to the control unit
being sure that the lead wires are not twisted.
3) After aluminium foil is removed, be careful that abnormal
voltage due to static electricity etc. is not applied to the
input or output terminals.
4) Attach connectors, electrolytic capacitors, etc. to PWB,
making sure that all connections are tight.
5) Be sure to use specified components where high
precision is required.
29
R-820BK
R-820BW
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE
WARNING AGAINST HIGH VOLTAGE:
Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may
result in severe, possibly fatal, electric shock.
(Example)
High Voltage Capacitor, Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc..
WARNING:
Avoid possible exposure to microwave energy. Please follow the instructions below before
operating the oven.
1. Disconnect the power supply cord.
2. Make sure that a definite "click" can be heard when the
microwave oven door is unlatched. (Hold the door in a
closed position with one hand, then push the door open
button with the other, this causes the latch leads to rise,
it is then possible to hear a "click" as the door switches
operate.)
3. Visually check the door and cavity face plate for damage
(dents, cracks, signs of arcing etc.).
1.
2.
3.
4.
5.
6.
Door does not close firmly.
Door hinge, support or latch hook is damaged.
The door gasket or seal is damaged.
The door is bent or warped.
There are defective parts in the door interlock system.
There are defective parts in the microwave generating
and transmission assembly.
7. There is visible damage to the oven.
Do not operate the oven:
1. Without the RF gasket (Magnetron).
2. If the wave guide or oven cavity are not intact.
3. If the door is not closed.
4. If the outer case (cabinet) is not fitted.
Carry out any remedial work that is necessary before
operating the oven.
Do not operate the oven if any of the following conditions
exist;
WARNING FOR WIRING
To prevent an electric shock, take the following precautions.
1. Before wiring,
1) Disconnect the power supply cord.
2) Open the door and block it open.
3) Discharge the high voltage capacitor and wait for 60
seconds.
2. Don’t let the wire leads touch to the followiong parts;
1) High voltage parts:
Magnetron, High voltage transformer, High voltage
capacitor and High voltage rectifier assembly.
2) Hot parts:
Oven lamp, Magnetron, High voltage transformer,
grill heater, bottom heater and Oven cavity.
3) Sharp edge:
Bottom plate, Oven cavity, Waveguide flange,
Chassis support and other metallic plate.
4) Movable parts (to prevent a fault)
Fan blade, Fan motor, Switch, Switch lever, Open
button.
3. Do not catch the wire leads in the outer case cabinet.
4. Insert the positive lock connector until its pin is locked
and make sure that the wire leads do not come off even
if the wire leads are pulled.
5. To prevent an error function, connect the wire leads
correctly, referring to the Pictorial Diagram.
Please refer to ‘OVEN PARTS, CABINET PARTS, CONTROL PANEL PARTS, DOOR PARTS’, when carrying out any of
the following removal procedures:
OUTER CASE REMOVAL
To remove the outer case, proceed as follows.
1. Disconnect the power supply cord.
2. Open the oven door and block it open.
3. Remove the two (2) screws (LHSTIX screws) holding the
back plate to the oven cavity rear plate, by using LHSTIX
screw driver (LHSTIX "LR-4").
4. Remove the back plate with the sub back plate.
5. Remove the two (2) screws from the lower portion of the
rear cabinet using a T20H Torx type or GTXH20-100
screw driver.
6. Remove the remaining three (3) screws from rear and
along the side edge of case.
7. Slide the entire case back about 3cm to free it from
retaining clips on the cavity face plate.
30
R-820BK
R-820BW
8. Lift the entire case from the oven.
9. Discharge the H.V. capacitor before carrying out any
further work.
10.Do not operate the oven with the outer case removed.
CAUTION: 1. DISCONNECT OVEN FROM POWER SUP
PLY BEFORE REMOVING OUTER CASE.
2. DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN
COMPONENTS OR WIRING.
NOTE: When replacing the outer case, the 2 special
Torx screws must be reinstalled in the same
locations.
Outer Case Cabinet
Sub Back Plate
Back Plate
Special
screw
LHSTIX Screw
LHSTIX
Screw
Driver(Size LR-4)
Screw Driver
(Type: TORX T20 H or
GTXH20-100)
POWER TRANSFORMER REMOVAL
1. Disconnect the power supply cord and then remove
outer case.
2. Open the oven door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the filament leads of power transformer from
high voltage capacitor and the magnetron.
5. Disconnect the H.V. wire B from the power transformer.
6. Disconnect the main wire harness from the power
transformer.
7. Remove the two (2) screws holding the transformer to
base plate.
8. Remove the transformer.
9. Now the power transformer is free.
HIGH VOLTAGE RECTIFIER ASSEMBLY AND HIGH VOLTAGE CAPACITOR REMOVAL
To remove the components, proceed as follows.
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 H.V. wire of the high voltage rectifier assembly
from the magnetron.
5. Disconnect all the leads and terminals of high voltage
rectifier assembly from the high voltage capacitor.
6. Remove one (1) screw holding earth side terminal of the
high voltage rectifier assembly.
7. Now, the high voltage rectifier assembly should be free.
8. Remove one (1) screw holding capacitor holder to the
oven cavity rear plate.
9. Release the capacitor holder from the fan duct.
10.Remove the capacitor from the capacitor holder.
11.Now, the capacitor should be free.
CAUTION: WHEN REPLACING HIGH VOLTAGE RECTIFIER AND HIGH VOLTAGE CAPACITOR,
GROUND SIDE TERMINAL OF THE HIGH
VOLTAGE RECTIFIER MUST BE SECURED
FIRMLY WITH A GROUNDING SCREW.
MAGNETRON REMOVAL
1. Disconnect the power supply cord and remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Release the tabs of air intake duct from the chassis
support and the oven cavity.
5. Disconnect the high voltage wire of the high voltage
rectifier assembly and filament lead of the transformer
from the magnetron.
6. Remove the one (1) screw holding the chassis support
to the magnetron.
7. Move the air intake duct to the left.
8. Carefully remove four (4) screws holding magnetron to
waveguide, when removing the screws hold the
magnetron to prevent it from falling.
9. Remove the magnetron from the waveguide with care so
the magnetron antenna is not hit by any metal object
around the antenna.
CAUTION: WHEN REPLACING THE MAGNETRON, BE
SURE THE R.F. GASKET IS IN PLACE AND
THE MAGNETRON MOUNTING SCREWS
ARE TIGHTENED SECURELY.
CONTROL PANEL ASSEMBLY REMOVAL
CONTROL PANEL ASSEMBLY
1. Disconnect the power supply cord and then remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
31
R-820BK
R-820BW
4. Disconnect the main wire harness, thermistor harness and
the switch harness from the power unit.
5. Straighten the tab of the oven cavity front flange holding
the tab of the control panel frame.
6. Lift up the control panel assembly.
7. Now, the control panel assembly is free.
CONTROL UNIT
8. Disconnect the flat ribbon cable from the connector CN-G.
9. Remove the two (2) screws holding the CPU unit to the
control panel frame.
10.Release the four (4) tabs of the control panel frame
holding the CPU unit to the control panel frame.
11.Release the liquid crystal display (LCD) from the LCD
holder.
12.Now, the LCD sheet is free.
13.Release the two (2) tabs of the LCD holder holding the
CPU unit to the LCD holder.
14.Remove the LCD holder from the CPU unit.
15.Remove the two (2) screws holding the power unit to the
control panel frame.
16.Release the four (4) tabs of the control panel frame
holding the power unit to the control panel frame.
17.Now, the control unit (CPU unit + Power unit) is free.
NOTE: 1. Before attaching a new key unit, wipe off remaining
adhesive on the control panel frame surfaces
completely with a soft cloth soaked in alcohol.
2. When attaching the key unit to the control panel
frame, adjust the upper edge and right edge of
the key unit to the correct position of control panel
frame.
3. Stick the key unit firmly to the control panel frame
by rubbing with soft cloth not to scratch.
OVEN LAMP AND LAMP SOCKET REMOVAL
Oven lamp
socket
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. Lift up the oven lamp socket from air intake duct.
5. Pull the wire leads from the oven lamp socket by pushing
the terminal hole of the oven lamp socket with the small
flat type screw driver.
6. Now, the oven lamp socket is free.
Terminal
Wire lead
Terminal hole
Flate type small
screw driver
Figure C-1. Oven lamp socket
POSITIVE LOCK® CONNECTOR (NO-CASE TYPE) REMOVAL
Terminal
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. Push the lever of positive lock® connector.
5. Pull down on the positive lock® connector.
Positive lock®
connector
4
Push
Lever
CAUTION: WHEN CONNECTING THE POSITIVE LOCK®
CONNECTORS TO THE TERMINALS, INSTALL THE POSITIVE LOCK® SO THAT THE
LEVER FACES YOU
5
Pull down
Figure C-2. Positive lock® connector
TURNTABLE MOTOR REMOVAL
1. Disconnect the power supply cord.
2. Remove the turntable motor cover by snipping of material
in four corners.
3. Where the corners have been snipped off, bend corner
areas flat. No sharp edge must be evident after removal
of turntable motor cover.
4. Disconnect the wire leads from the turntable motor and
remove the two (2) screws holding the turntable motor.
5. Now, the turntable motor is free.
6. After replacement use the one (1) screw provided with
the turntable motor assembly to fit turntable motor cover.
NOTE: The one (1) screw to fit the turntable motor cover
should be XFPSD40P12K00, XFPSD40P10K00 or
XFPSD40P08K000.
32
R-820BK
R-820BW
COOLING FAN MOTOR REMOVAL
REMOVAL
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 wire leads from the fan motor.
5. Remove the one (1) screw holding the capacitor holder
to the oven cavity rear plate.
6. Remove the one (1) screw holding the fan duct to the
oven cavity rear plate.
7. Release the tabs of the capacitor holder from fan duct.
8. Remove the fan duct from the oven.
9. Remove the fan blade from the fan motor shaft according
to the following procedure.
10.Hold the edge of the rotor of the fan motor by using a pair
of groove joint pliers.
CAUTION:
* Make sure that no metal pieces enter the gap
between the rotor and the stator of the fan motor
because the rotor is easily shaven by pliers and
metal pieces may be produced.
* Do not touch the pliers to the coil of the fan motor
because the coil may be cut or injured.
* Do not disfigure the bracket by touching with the
pliers.
11.Remove the fan blade from the shaft of the fan motor by
pulling and rotating the fan blade with your hand.
12. Now, the fan blade will be free.
CAUTION:
* Do not reuse the removed fan blade because the
hole (for shaft) may be larger than normal.
13.Remove the two (2) screws holding the fan motor to the
fan duct.
14.Now, the fan motor is free.
INSTALLATION
1. Install the fan motor to the fan duct with the two (2)
screws.
2. Install the fan blade to the fan motor shaft according to
the following procedure.
3. Hold the center of the bracket which supports the shaft
of the fan motor on the flat table.
4. Install the fan blade to the shaft of fan motor by pushing
the fan blade with a small, light weight, ball peen hammer
or rubber mallet.
CAUTION:
* Do not hit the fan blade hard when installing because
the bracket may be disfigured.
* Make sure that the fan blade rotates smooth after
installation.
* Make sure that the axis of the shaft is not slanted.
5. Install the fan duct to the oven cavity rear plate with the
one (1) screw.
6. Insert the tabs of the capacitor holder to the fan duct.
7. Install the capacitor holder to the oven cavity rear plate
with the one (1) screw.
8. Re-connect the wire leads to the fan motor.
Coil
Shaft
Groove joint pliers
Stator
Gap
Bracket
Table
Shaft
Axis
Rotor
Rear View
These are the positions
that should be pinched
with pliers
Stator
Side View
Center of
bracket
Rotor
CONVECTION MOTOR REMOVAL
11.Remove the three (3) screws holding the convection
duct to the conv. thermal cover.
12.Remove the convection duct with the conv. air angles
from the conv. thermal cover.
13.Remove the thermal insulation.
14.Remove the one (1) pipe holding the cooling fan to the
convection motor shaft.
15.Remove the cooling fan and the one (1) washer from the
convection motor shaft.
16.Remove the two (2) screws holding the convection motor
to the conv. thermal cover.
17.Remove the convection motor from the conv. thermal
cover.
18.Remove the one (1) ring from the convection motor
shaft.
19.Now, the convection motor is free.
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. Now, the back plate with the sub back plate should be
removed.
5. Disconnect the wire leads from the convection motor.
6. Remove the two (2) screws holding the conv. thermal
cover to the oven cavity rear plate.
7. Remove the four (4) screws holding the convection
duct to the oven cavity rear plate.
8. Remove the convection duct assembly from the oven
cavity rear plate.
9. Remove the one (1) nut and the two (2) washers holding
the convection fan to the convection motor shaft.
10.Remove the convection fan.
33
R-820BK
R-820BW
THERMISTOR REMOVAL
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. Now, the back plate with the sub back plate should be
removed.
5. Disconnect the connector CN-D from the control unit.
6. Remove the one (1) screw holding the air duct to the
oven cavity rear plate.
7. Remove the air duct with the air guide cover and the
partition plate from the oven cavity rear plate.
8. Remove the one (1) screw holding the thermistor angle
to the oven cavity rear plate.
9. Remove the thermistor angle together with thermistor
from the oven.
10.Straighten the tab of the thermistor angle holding the
thermistor to the thermistor angle.
11.Remove the thermistor from the thermistor angle
POWER SUPPLY CORD REPLACEMENT
Removal
cavity rear plate with one (1) screw and tighten the screw.
3. Connect the brown and blue wire leads of power supply
cord to the main wire harness correctly, referring to the
Pictorial Diagram.
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. Remove the one (1) screw holding the green wire to the
cavity rear plate.
5. Disconnect the leads of the power supply cord from the
main wire harness.
6. Release the power supply cord from the oven cavity rear
plate.
7. Now, the power supply cord is free.
Moulding
Cord Stopper
Power
Supply Cord
Oven Cavity
Rear Plate
Re-install
1. Insert the moulding cord stopper of power supply cord
into the square hole of the oven cavity rear plate,
referring to the Figure C-3.
2. Install the earth wire lead of power supply cord to the
Square Hole
Figure C-3. Power Supply Cord Replacement
GRIL HEATER (TOP HEATER) REMOVAL
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. Remove the one (1) screw holding the exhaust duct to
the oven cavity.
5. Remove the exhaust duct from the oven cavity.
6. Disconnect the wire leads from the grill heaters.
7. Lay down the two (2) tabs holding the reflector to the
oven cavity.
8. Remove the reflector from the oven cavity by sliding it
leftward.
9. Remove the grill heaters and the short terminal together
from the oven cavity top plate.
10.Remove the two (2) screws holding the short terminal to
the grill heaters.
11.Now the individual grill heaters are free.
BOTTOM HEATER REMOVAL
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. Remove the fan duct from the oven cavity, referring to
"FAN MOTOR REPLACEMENT".
5. Disconnect the wire leads from the bottom heater.
6. Remove the two (2) nuts holding the bottom heater with
the bottom heater angle and the heat seal spring to the
oven cavity right wall.
7. Remove the two (2) nuts holding the bottom heater with
the bottom heater angle and the heat seal spring to the
oven cavity left wall.
8. Remove the bottom heater from the oven cavity .
DOOR SENSING SWITCH/SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH REMOVAL
2. Open the door and block it open.
3. Discharge high voltage capacitor.
1. Disconnect the power supply cord and then remove
outer case.
34
R-820BK
R-820BW
4. Remove the control panel assembly referring to
"CONTROL PANEL ASSEMBLY REMOVAL".
5. Disconnect the leads from all switches.
6. Remove the two (2) screws holding the latch hook to the
oven cavity.
7. Remove the latch hook.
8. Push the retaining tab slightly and remove the switch.
Latch Hook
Door
Sensing
Switch
Tab
Monitor Switch
Tab
Secondary
Interlock
Switch
Tab
Figure C-4. Switches
DOOR SENSING SWITCH/SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH ADJUSTMENT
1. Disconnect the power supply cord and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
If the door sensing switch, secondary interlock switch and
monitor switch do not operate properly due to a
misadjustment, the following adjustment should be made.
4. Loosen the two (2) screws holding latch hook to the oven
cavity front flange.
5. With door closed, adjust latch hook by moving it back and
forth, and up and down. In and out play of the door
allowed by the upper and lower position of the latch hook
should be less than 0.5mm. The vertical position of the
latch hook should be adjusted so that the door sensing
switch and secondary interlock switch are activated with
the door closed. The horizontal position of the latch hook
should be adjusted so that the plunger of the monitor
switch is pressed with the door closed.
6. Secure the screws with washers firmly.
7. Check the operation of all switches. If each switch has
not activated with the door closed, loosen screw and
adjust the latch hook position.
hook, pushing and pulling upper portion of door toward
the oven face. Then check lower portion of the latch
hook, pushing and pulling lower portion of the door
toward the oven face. Both results (play in the door)
should be less than 0.5mm.
2. The door sensing switch and secondary interlock switch
interrupt the circuit before the door can be opened.
3. Monitor switch contacts close when door is opened.
4. Re-install outer case and check for microwave leakage
around door with an approved microwave survey meter.
(Refer to Microwave Measurement Procedure.)
Latch
Heads Latch Hook
Door
Sensing
Switch
Door
After adjustment, check the following.
1. In and out play of door remains less than 0.5mm when in
the latched position. First check upper position of latch
Switch
Lever
Monitor
Switch
Secondary
Interlock
Switch
Figure C-5. Latch Switch Adjustments
DOOR REPLACEMENT
REMOVAL
1. Disconnect the power supply cord.
2. Push the open button and open the door slightly.
3. Insert a putty knife (thickness of about 0.5mm) into the
gap between the choke cover and door frame as shown
in Figure C-6 to free engaging parts.
4. Pry the principles of the lever and lift up the choke cover
by inserting a putty knife as shown in Figure C-6.
5. Release choke cover from door panel.
6. Now choke cover is free.
Choke Cover
Putty Knife
Door Frame
Figure C-6. Door Disassembly
35
R-820BK
R-820BW
7. Release two (2) pins of door panel from two (2) holes of
upper and lower oven hinges by lifting up.
8. Now, door sub assembly is free from oven cavity.
9. Remove the four (4) screws holding the door panel to the
door frame.
10.Release door panel from seven (7) tabs of door frame by
sliding door panel downward.
11.Now, door panel is free.
12.Slide latch head upward and remove it from door frame
with releasing latch spring from door frame and latch
head.
13.Now, latch head and latch spring are free.
14.Remove the two (2) screws holding the glass stopper to
the door frame.
15.Remove the glass stopper from the door frame.
16.Slide the front door glass left and then slide upwards to
release the tabs holding it.
17.Now, the front door glass is free
face plate is to be less than 1.0mm.
3. Door is positioned with its face pressed toward cavity
face plate.
4. Check for microwave leakage around door with an
approved microwave survey meter. (Refer to Microwave
Measurement Procedure.)
Note: The door on a microwave oven is designed to act as
an electronic seal preventing the leakage of microwave
energy from oven cavity during cook cycle. This
function does not require that door be air-tight,
moisture (condensation)-tight or light-tight. Therefore,
occasional appearance of moisture, light or sensing
of gentle warm air movement around oven door is not
abnormal and do not in themselves indicate a leakage
of microwave energy from oven cavity.
Pin
Upper
Oven
Hinge
Upper Oven
Hinge
RE-INSTALL
1. Re-install the front door glass to the door frame as
follows.
1-1. Insert the lower edge of the front door glass into the six
(6) tabs of the door frame.
1-2. Slide the front door glass upwards and insert the upper
edge of the front door glass into the five (5) tabs of the
door frame.
1-3. Slide the front door glass right and insert the right edge
of the front door glass into the two (2) tabs of the door
frame.
2. Re-install the glass stopper to the door frame as follows.
2-1. Re-install the glass stopper to the door frame so that the
two (2) holes of the glass stopper meet the two (2) pins
of the door frame.
2-2. Hold the glass stopper to the door frame with the two (2)
screws.
3. Re-install the latch spring to the latch head. Re-install the
latch spring to the door frame. Re-install latch head to
door frame.
4. Re-install door panel to door frame by fitting seven (7)
tabs of door frame to seven (7) holes of door panel.
5. Hold the door panel to the door frame with four (4)
screws.
6. Catch two (2) pins of door panel on two (2) hole of upper
and lower oven hinges.
7. Re-install choke cover to door panel by pushing.
Note: After any service to the door;
(A) Make sure that door sensing switch and secondary
interlock switch are operating properly. (Refer to
chapter "Test Procedures".).
(B) An approved microwave survey meter should be
used to assure compliance with proper microwave
radiation emission limitation standards. (Refer to
Microwave Measurement Procedure.)
Door
Panel
Lower
Oven
Hinge
Choke Cover
Pin
Lower
Oven
Hinge
Figure C-7. Door Replacement
After any service, make sure of the following :
1. Door latch heads smoothly catch latch hook through
latch holes and that latch head goes through center of
latch hole.
2. Deviation of door alignment from horizontal line of cavity
36
R-820BK
R-820BW
2
4
3
Q2 2SB1238
R4 27
A
D1-4
11ES1
(J1)
B
+
D2
+
D4
b
–
a
LED
C2
GND
A
R5 4.7k
C3 0.1µ/50v
6
d 1
C10
D1
D3
–
4
D6
D5
C1 0.1µ/50v
VRS1
10G471K
8
A1
C2 470µ/50v
T1
AC120V
60Hz
6
5
C4 10µ/35v
1
B
C3
VC
C1
VA
C9
VR
C4
INT
R3 510 1/2w
R2 510 1/2w
c
SP1
C
C
D12
RY5
FAN MOTOR
C5
BUZZER
C15
FAN MOTOR
C16
CONVECTION
MOTOR
C6
OVEN LAMP
TURNTABLE
MOTOR
C14
BOTTOM
HEATER
R6 3.3k
A3
D7
RY1
CONVECTION
MOTOR
RY6
Q3
DTD143ES
COM
–
C5
10µ/35v
RY4
BOTTOM
HEATER
N.O.
D10
E
D
N.O.
+
OVEN LAMP
TURNTABLE
MOTOR
A5
D11
D
E
COM
RY3
C8
TOP
HEATER
TOP
HEATER
D9
N.O.
COM
C11
N.C.
C7
MICRO
C17
OVEN
THERMISTOR
C13
N.C.
C12
DOOR
SWITCH
RY2
F
F
D8
N.O.
MICRO
COM
G
G
D3
D1
B2
B1
DOOR SWITCH
OVEN THERMISTOR
: IF NOT SPECIFIED, 1/4w ± 5%
NOTE
: IF NOT SPECIFIED, 1SS270A
H
H
Figure S-2. Power Unit Circuit
1
2
4
3
38
5
6
C15
C16
FAN
MOTOR
CONVECTION
MOTOR
5
OVEN
THERMISTOR
C17
C13
C12
D30
D23
Q20
DTA123JKA
C7
MICRO
DOOR
SWITCH
Q21
DTA123JKA
C14
C21
0.1µ/50v
Q22
DTA123JKA
Q23
DTA143EKA
Q24
DTA143EKA
Q25
DTA143EKA
LD10 LD9 LD8 LD7 LD6
BOTTOM
HEATER
C11
C11 0.1µ/50v
LD1 LD2 LD3 LD4 LD5
C8
D22
+
–
Q40
DTA143EKA
C10 47µ/16v
TOP
HEATER
OVEN LAMP
TURNTABLE C 6
MOTOR
C9
C10
LED
VR
C1
C5
BUZZER
VA
C3
VC
C13
0.1µ/50v
R30 4.7k
C30
Q11
DTA143EKA
R81
C14
C2
R31 15k
R10 1k
C80
(J15) 4.7k
(J14) 4.7k
(J12)
(J11)
(J10)
C63 330p/50v
C62 330p/50v
C61 330p/50v
C60 330p/50v
R75 100k
R74 100k
R73 100k
R72 100k
C1
VL1
AN7
AN6
AN5
AN4
AN3
AN2
AN1
AN0
P57
P56
P55
P54
P53
P52
P51
P50
P47
P46
P45
P44
INT1
INT0
P41
P40
P77
P76
P75
P74
51
30
25
20
15
10
5
80 SEG10
SEG11
SEG12
SEG13
SEG14
75 SEG15
SEG16
SEG17
SEG18
SEG19
70 SEG20
SEG21
SEG22
SEG23
SEG24
65 SEG25
SEG26
SEG27
SEG28
SEG29
60 SEG30
SEG31
SEG32
SEG33
SEG34
55 SEG35
SEG36
SEG37
SEG38
SEG39
MINUTE
PLUS
CLOOK
DEFROST
PIZZA
GRILL
6
ROAST
7
REHEAT
8
9
POWER
LEVEL
0
START
TOUCH ON
ROAST
G3
1
KITCHEN
TIMER
GRILL
G4
2
3
G5
G6
4
5
G8
G7
CF1 4.19MGW
R56
1M
G2
POPCORN
CONVEC
COOK
BAKE
G1
CUSTOM
HELP
STOP
CLEAR
1
5
D
6
R14
1k
R70 15k
R69 15k
Figure S-3. CPU Unit Circuit
R80 150kF
Q10
2SA1037AK
(J13) 4.7k
ZD10
UDZ4.3B
R82 9.1kF
GND
R11 4.7k
C4
95
C12
0.1µ/50v
R68 15k
C2
VL2
VL3
COM0
COM1
COM2
COM3
AVSS
VREF
VCC
SEG0
SEG1
SEG2
SEG3
SEG4
SEG5
SEG6
SEG7
SEG8
SEG9
90
R13
1k
R12
1k
R15 4.7k
COOK
HELP
4
R83 15k
0
39
R55 4.7k
4
R60 15k
3
(J1)
G
R61 15k
2
85
INT
R63 15k
: IF NOT SPECIFIED, 0.01µF / 25v
R64 15k
: IF NOT SPECIFIED, 1/10 ± 5%
R65 15k
: IF NOT SPECIFIED, 1SS355
R66 15k
1
R67 15k
H
IC-1
RH-IZA888DR
E
R71 15k
C
3
G12 G11 G10 G 9
B
SEG45
SEG44
SEG43
SEG42
SEG41
SEG40
SEG39
SEG38
SEG37
SEG36
SEG35
SEG34
SEG33
SEG32
COM5
COM4
COM3
COM2
COM1
SEG15
SEG31
SEG30
SEG29
SEG28
SEG27
SEG26
SEG25
SEG24
SEG23
SEG22
SEG21
SEG20
SEG19
SEG18
SEG17
SEG16
SEG15
SEG14
SEG13
SEG12
SEG11
SEG10
SEG9
SEG8
SEG7
SEG6
SEG5
SEG4
SEG3
SEG2
SEG1
F
2
P73
P72
P71
P70
RESET 35
P81
P80
XIN
XOUT
VSS
P27
P26
P25
P24
45
P23
P22
P21
P20
P17
50
P16
1
R62 15k
NOTE
R-820BK
R-820BW
6
A
A
B
C
D
E
F
G
H
R-820BK
R-820BW
2
1
4
3
6
5
DIP
A
A
R3
CN - C 18
B
1
1
2
D6
CN - D
3
Q1
B
3
R4
E
Q2
B
C3
C4
R6
D9
D10
D8
B
R5
D5
1
CN - B
4
D11
RY6
1
R1
E
R2
C2
AC
2
ZD1
C5
E
Q3
SP1
C
B
C
D3
D1
C1
RY3
T-H
D
D
1
D2
8
RY4
B-H
D4
E
6
RY2
MICRO
E
S
P
4
VRS1
F
F
T1
5
(J1)
FAN
1
5
CON
AC
G
RY1
G
6
LOT NO.
D12
D7
CN - A
RY5
F
H
H
Figure S-4. Printed Wiring Board of Power Unit
1
2
4
3
40
5
6
R-820BK
R-820BW
PARTS LIST
Note: The parts marked “ ∆” may cause undue microwave exposure.
The parts marked “*” are used in voltage more than 250V.
REF. NO.
PART NO.
DESCRIPTION
Q'TY
CODE
2
2
1
1
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
AH
AG
AL
AR
AS
AN
AX
AV
AX
AG
AD
AW
AP
AX
AD
AU
BA
AE
AG
AH
AK
BP
BN
BL
1
1
1
1
1
AW
BB
AZ
AX
AC
1
1
1
2
1
1
1
1
2
4
3
5
1
1
2
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
1
1
1
1
BF
AC
AB
AK
AB
AA
AE
AA
AA
AB
AA
AA
AA
AC
AB
AB
AA
AA
AG
AL
AK
AG
AK
AG
AQ
AE
BC
BA
BB
AF
AF
AB
AX
AX
ELECTRIC PARTS
*
*
*
*
∆*
∆*
1- 1
1- 1
1- 2
1- 3
1- 3
1- 4
1- 5
1- 5
1- 6
1- 7
1- 7
1- 8
1- 9
1-10
1-11
1-12
1-13
1-14
1-15
1-16
1-17
1-18
1-19
1-19
QSW-MA110WRE0
QSW-MA131WRE0
FFS-BA021WRK0
RMOTDA231WRE0
RMOTDA188WRE0
FH-DZA025WRK0
RC-QZA173WRE0
RC-QZA211WRE0
RMOTEA370WRE0
QFSHDA009WRE0
QFSHDA010WRE0
FACCDA074WRE0
FH-HZA063WRE0
RMOTEA372WRE0
QTANNA017WRW0
RHET-A208WRE0
RHET-A209WRE0
RLMPTA030WRE0
QSOCLA021WRE0
RTHM-A048WRE0
RTHM-A078WRE0
RTRN-A568WRE0
RV-MZA222WRE0
RV-MZA267WRE0
Secondary interlock switch / door sensing switch
Secondary interlock switch / door sensing switch (Interchangeable)
Monitor fuse and monitor switch assembly
Turntable motor
Turntable motor (Interchangeable)
High voltage rectifier assembly
High voltage capacitor
High voltage capacitor (Interchangeable)
Fan motor
Fuse holder
Fuse holder (Interchangeable)
Power supply cord
Thremistor
Convection motor
Short terminal
Grill heater (Top heater)
Bottom heater
Oven lamp
Oven lamp socket
Thermal cut-out 170 deg.
Thermal cut-out 125 deg.
Power transformer
Magnetron
Magnetron (Interchangeable)
22222-
1
2
2
3
4
GCABDA097WRW0
GCABUA631WRP0
GCABUA649WRP0
GDAI-A305WRW0
GLEGPA074WRE0
Back plate
Outer case cabinet [R-820BK]
Outer case cabinet [R-820BW]
Base plate
Leg
3- 1
3- 1A
3- 1B
3- 1C
3- 1D
C1
C2
C3
C4-5
D1-4
D5-7
D8-12
Q2
Q3
R2-3
R4
R5
R6
RY1
RY2
RY3-4
RY5
RY6
SP1
T1
VRS1
3- 2
3- 3
3- 3
3- 3-1
3- 3-1
3- 3-2
3- 3-3
3- 3-3
CPWBFA791WRK0
QCNCMA234DRE0
QCNCMA275DRE0
FW-VZA238DRE0
QCNCMA410DRE0
RC-KZA087DRE0
VCEAB31HW477M
RC-KZA087DRE0
VCEAB31VW106M
VHD11ES1///-1
VHD1SS270A/-1
VHD1SS270A/-1
VS2SB1238//-3
VSDTD143ES/-3
VRD-B12HF511J
VRD-B12EF270J
VRD-B12EF472J
VRD-B12EF332J
RRLY-A080DRE0
RRLY-A081DRE0
RRLY-A076DRE0
RRLY-A080DRE0
RRLY-A076DRE0
RALM-A014DRE0
RTRNPA124DRE0
RH-VZA032DRE0
DPWBFB794WRK0
DPNLCB494WRK0
DPNLCB496WRK0
JBTN-B086WRF0
JBTN-B092WRF0
MSPRCA050WRE0
FUNTKA869WRE0
FUNTKA871WRE0
Power unit
3-pin connector (CN-A)
2-pin connector (CN-B)
9pin wire harness (WH-1, WH-2)
2-pin connector (CN-D)
Capacitor
0.1 uF
50V
Capacitor
470 uF
50V
Capacitor
0.1 uF
50V
Capacitor
10 uF
35V
Diode (11ES1)
Diode (1SS270A)
Diode (1SS270A)
Transistor (2SB1238)
Transistor (DTD143ES)
Resistor
510 ohm
1/2W
Resistor
27 ohm
1/4W
Resistor
4.7k ohm
1/4W
Resistor
3.3k ohm
1/4W
Relay (OJ-SH-124LM)
Relay (VRB24)
Relay (OMIF-S-124LM)
Relay (OJ-SH-124LM)
Relay (OMIF-S-124LM)
Buzzer (PKM22EPT-THAI)
Transformer
Varistor (10G471K)
CPU unit
Control panel frame with key unit [R-820BK]
Control panel frame with key unit [R-820BW]
Open button [R-820BW]
Open button [R-820BK]
Open button spring
Key unit [R-820BK]
Key unit [R-820BW]
CABINET PARTS
CONTROL PANEL PARTS
41
R-820BK
R-820BW
REF. NO.
3- 4
3- 5
3- 6
3- 7
PART NO.
LHLD-A185WRF0
PSHEPA626WRE0
TCAUAA076WRR0
XEPSD30P08XS0
DESCRIPTION
LCD holder
LED sheet
User caution label
Screw; 3mm x 8mm
Oven cavity (Not a replaceable part)
Latch hook
Air duct assembly
Sub back plate
Turntable motor angle
Plate spring
Turntable motor shaft
Spacer
HV capacitor holder
Fan blade
Fan duct
Bottom heater cover
Leg
Chassis support
Thermistor angle
Bearing
Switch lever
Heat seal spring
Bottom heater angle
Waveguide cover
Cushion
Cushion
Cushion
Air intake duct
Exhaust duct
Air guide
Light glass
Cushion
Reflector
Heater film
Air separate angle
H-spring
Cushion
Convection fan
Cooling fan
Cushion
Convection duct
Thermal insulation
Pipe
Convection air angle
Convection motor angle A
Convection motor angle B
Convection thermal cover
Door panel assembly
Door frame [R-820BK]
Door frame [R-820BW]
Latch head
Glass stopper
Latch spring
Front door glass [R-820BK]
Front door glass [R-820BW]
Screw : 4mm x 6mm
Screw : 4mm x 8mm
Choke cover
Q'TY
1
1
1
4
CODE
AL
AF
AB
AA
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
1
2
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
2
1
1
1
-AL
BH
AQ
AP
AE
AN
AB
AQ
AF
AM
AF
AG
AM
AW
AM
AF
AF
AM
AF
AH
AC
AC
AG
AS
AT
AZ
AE
BE
AA
AY
AC
AE
AX
AX
AC
AR
AM
AK
AX
AU
AR
AQ
1
1
1
1
1
1
1
1
2
4
1
BB
AY
AX
AN
AF
AC
AV
AW
AA
AA
AS
1
1
1
1
1
1
1
1
1
AQ
AG
BC
BB
AB
AS
AG
AY
AF
OVEN PARTS
∆ 4- 1
∆
4- 2
4- 3
4- 4
4- 5
4- 6
4- 7
4- 8
4- 9
4-10
4-11
4-12
4-13
4-14
4-15
4-16
4-17
4-18
4-19
4-20
4-21
4-22
4-23
4-24
4-25
4-26
4-27
4-28
4-29
4-30
4-31
4-32
4-33
4-34
4-35
4-36
4-37
4-38
4-39
4-40
4-41
4-42
4-43
*************
PHOK-A106WRF0
FDUC-A337WRK0
PCOVPA340WRW0
LANGQA478WRP0
MSPRTA186WRE0
NCPL-A051WRE0
PSPA-A109WRE0
LBNDKA136WRP0
NFANJA041WRE0
PDUC-A697WRF0
GCOVHA388WRW0
GLEGPA071WRF0
LANGFA185WRP0
LANGQA489WRP0
LFLG-A025WRE0
MLEVPA226WRF0
MSPR-A004WRE0
PCOV-A011WRP0
PCOVPA339WRE0
PCUSGA385WRP0
PCUSUA190WRP0
PCUSUA191WRP0
PDUC-A691WRF0
PDUC-A692WRP0
PDUC-A696WRP0
PGLSPA518WRE0
PPACGA041WRE0
PREFHA061WRW0
PSHEPA487WRE0
PSKR-A331WRP0
MSPRCA113WRE0
PCUSGA420WRP0
NFANMA047WRP0
NFANMA048WRP0
PCUSUA499WRP0
PDUC-A707WRW0
PFPF-A210WRE0
PPIPFA030WRE0
PSKR-A339WRP0
PSKR-A345WRW0
PSKR-A346WRW0
PSLDHA140WRW0
∆
55555555555-
DDORFA857WRK0
GWAKPA570WRR0
GWAKPA572WRR0
LSTPPA176WRF0
LSTPPA177WRF0
MSPRTA187WRE0
PGLSPA513WRE0
PGLSPA514WRE0
XCPSD40P06000
XCPSD40P08000
GCOVHA387WRF0
DOOR PARTS
∆
∆
∆
1
2
2
3
4
5
6
6
7
8
9
MISCELLANEOUS
*
666666666-
1
2
3
4
5
6
7
8
9
FAMI-A104WRM0
TCAUAA145WRR0
FSRAHA062WRY0
NTNT-A097WRE0
TCAUAA200WRR0
TINSEA752WRR0
FW-VZB045WRE0
FW-VZB673WRE0
QW-QZA213WRE0
Rack
Earth caution
Turntable support
Turntable
Monitor caution
Instruction book
Switch harness
Main wire harness
High voltage wire B
42
R-820BK
R-820BW
REF. NO.
6-10
6-11
6-12
6-13
PART NO.
LHLDWA011WRE0
TCAUAA201WRR0
TCAUAA240WRR0
TLABMA570WRR0
DESCRIPTION
Purse lock M
DHHS caution label
Screw caution
Menu label
7- 1
7- 2
7- 3
7- 4
7- 5
7- 6
7- 7
7- 8
7- 9
7-10
7-11
7-12
7-12
7-13
7-14
7-15
7-16
7-17
7-18
7-19
XFPSD40P08K00
XEPSD40P25000
LX-EZA042WRE0
LX-NZ0061WRE0
XBPWW30P05K00
XCTWW40P08000
XHPSD30P06000
XHTSD40P08RV0
XOTSD40P12RV0
XOTSD40P12000
XOTSD40R12RV0
XOTSF40P08000
XOTSE40P08000
XBTSD40P05000
XNEUW40-32000
XRESE40-06000
XWHUW40-08000
XWHUW50-08000
XWSUW40-10000
LX-CZA070WRE0
Screw : 4mm x 8mm
Screw : 4mm x 25mm
Special screw
Flange nut
Screw : 3mm x 5mm
Screw : 4mm x 8mm
Screw : 3mm x 6mm
Screw : 4mm x 8mm
Screw : 4mm x 12mm
Screw : 4mm x 12mm
Line head screw : 4mm x 12mm
Screw : 4mm x 8mm [R-820BK]
Screw : 4mm x 8mm [R-820BW]
Screw : 4mm x 5mm
Nut : 4mm x 3.2mm
Ring : 4mm x 0.6mm
Washer : 4mm x 0.8mm
Washer : 5mm x 0.8mm
Washer : 4mm x 1.0mm
Special screw (Torx tamper proof screw)
Q'TY
1
1
1
1
CODE
AB
AC
AC
AF
13
2
2
4
2
8
1
2
12
10
2
1
1
2
1
1
1
1
1
2
AA
AA
AB
AA
AA
AB
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AA
AC
SCREWS,NUTS AND WASHERS
HOW TO ORDER REPLACEMENT PARTS
To have your order filled promptly and correctly, please furnish the following information.
1. MODEL NUMBER
2. REF. NO.
3. PART NO.
4. DESCRIPTION
Order Parts from the authorized SHARP parts Distributor for your area.
Defective parts requiring return should be returned as indicated in the Service Policy.
PACKING AND ACCESSORIES
TOP PAD ASSEMBLY
(FPADBA381WRK0)
TRAY HOLDER
(SPADFA424WRE0)
WRAP COVER
TURNTABLE TRAY
(SSAKHA034WRE0)
RACK
DOOR PROTECTION SHEET
(SPADPA204WRE0)
LAMP CAUTION
COOK BOOK &
INSTRUCTION BOOK
BOTTOM PAD ASSEMBLY
TURNTABLE SUPPORT
(FPADBA382WRK0)
TRAY PAD
(SPADPA577WRE0)
PACKING CASE
Not Replaceable Items.
SPAKCD092WRE0 [R-820BK]
SPAKCD095WRE0 [R-820BW]
43
R-820BK
R-820BW
2
1
4
3
OVEN AND CABINET PARTS
6
5
7-9
2-2
7-19
7-9
A
A
6-11
7-11
7-9
2-1
7-19
4-33
6-2
4-4
7-10
B
B
4-25
7-11
7-12
4-29
7-5
4-36
7-10
4-23
4-3
1-11
4-26
4-41
1-12
7-10
C
7-17
4-27
7-4
7-10
1-16
4-30
4-39
1-9
4-42
1-14
4-18
7-10
1-15
1-8
4-35
4-40
4-43
7-13
6-12
4-1
D
C
4-38
7-1
6-13
7-10
7-13
7-10
4-31
4-19
4-32
7-15 1-10
4-15
7-6
4-34 x3
A
7-8
D
4-37
7-16
7-6
7-18
7-14
7-8
7-10
7-6
6-5
6-7
7-6
4-24
7-7
7-9
1-13
1-17
E
7-1
4-16
4-6
E
4-18
4-32
4-21
4-19
4-11
7-4
4-2
4-5
6-4
4-14
7-10
7-1
4-7
4-8
4-20
A
4-40
1-5
1-6
7-2
1-4
4-10
1-1
1-3
F
7-1
F
1-7
7-1
7-1
4-12
4-9
7-1
6-3
1-2
1-1
7-3
4-22
1-18
1-19
4-17
7-1
G
G
4-28
2-3
4-13
7-9
2-4
H
H
7-9
2-4
1
2
7-9
4
3
44
5
6
R-820BK
R-820BW
2
1
4
3
6
5
3-7
CONTROL PANEL PARTS
3-4
A
A
3-5
3-2
3-3
3-7
B
B
3-3-3
3-6
3-1
C
C
DOOR PARTS
3-3-1
D
D
5-8
3-3-2
5-9
5-1
E
E
5-6
5-2
5-7
F
F
5-3
5-4
5-5
MISCELLANEOUS
G
G
6-8
6-1
6-7
Actual wire harness may be different from illustration.
6-10
H
H
6-9
1
2
4
3
45
5
6
R-820BK
R-820BW
COPYRIGHT © 1998 BY SHARP CORPORATION
ALL RIGHTS RESERVED.
No part of this publication may be reproduced, stored in retrieval systems, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of the publisher.
'98 SHARP CORP. (5S2.530E) Printed in U.S.A
46