Sharp R-8470, R-8570 Service Manual

Page 1
SHARP SERVICE MANUAL
S9610R8470Jll
COUNTER TOP
CONVECTION
MICROWAVE OVEN
Photo R-8470
In the interests of user-safety the set should be restored to its original
TABLE OF CONTENTS
Page
FOREWORD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ............................... 1
CAUTION, MICROWAVE
RADIATION
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
PRODUCT DESCRIPTION
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....... 2
OPERATION INSTRUCTIONS
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3
OPERATION
....................................................................................
.I.. ...............................................................
4
SERVICING .....................................................................................................................................................
10
TOUCH CONTORL
PANEL ASSEMBLY
.....................................................................................................
20
COMPORNENT
REPLACEMENT AND ADJUSTMENT
PROCEDURE
...................................................
29
MICROWAVE MEASUREMENT
PROCEDURE
.......................................................................................... 34
PACKING AND ACCESSORIES
...................................................................................................................
35
PICTORIAL DIAGRAM
..................................................................................................................................
36
CONTROL PANEL
CIRCUIT (R-8470)
.......................................................................................................
37
CONTROL PANEL
CIRCUIT (R-8570)
....................................................................................................... 39
PRINTED WIRING
BOARD ..........................................................................................................................
41
PARTS LIST .................................................................................................................................................... 42
SERVICE INFORMATION
FOR CONTROL
UNIT ...................................................................................... 47
SHARPCORPORATION
Page 2
I--
R-8470 R-8570
(R-8470)
(R-8570)
Page 3
R-8470 R-8570
SERVICE MANUAL
SHARP
COUNTER
TOP
/
CONVECTION MICROWAVE
OVEN
R-8470/ R-8570
FOREWORD
/
This Manual has been prepared to provide Sharp Corp. Service
Personnel with complete Operation and Service Information for
the SHARP CONVECTION MICROWAVE ovens, R-8470/
1
R-8570.
1
It is recommended that service personnel carefully study
the
entire text of this manual so they will be qualified to render satisfactory customer service.
Check interlock switches and door seal carefully. Special at-
tention should be given to avoid electrical shock and microwave
radiation hazard.
CAUTION
MICROWAVE RADIATION
Personnel should not be exposed to the microwave energy
which may radiate from the magnetron or other microwave
generating devices if it is improperly used or connected. All input and output microwave connections, waveguides,flanges and gaskets must be secured. Never operate the device without a nicrowave energy absorbing load attached. Never look into
an open waveguide or antenna while the device is energized.
SHARPCORPORATION
OSAKA, JAPAN
$4 ”
PRODUCT
DESCRIPTION
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OPERATION
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CONTROL
COMPONENT
REPLACEMENT AND
ADJUSTMENT
MICROWAVE MEASUREMENT
*
PARTS
LIST
Page 4
R-8470 R-8570
PRODUCTION DESCRIPTION
EXPLANATION OF MICROWAVE COOKING AND CONVECTION COOKING
The Sharp Convection-Microwave Oven uses micro-
cules are changing direction every half cycle or oscil-
wave energy and the sheath heater to produce heat in
lating back and forth 4,900,000,000 times per second.
the food to be cooked.
This high speed oscillation causes friction between the
Unlike conventional ovens microwave energy will cook
foods without applying external heat.
molecules, thereby converting the microwave energy to heat.
Microwaves, which are short electromagnetic waves of RF (radio frequency) energy, pass through materials guch as glass, paper, china and most plastics. Materi­als such as metal and aluminum foil tend to reflect microwaves and may be used only as recommended in the cooking instructions.
Materials with a high moisture content, like most foods, will absorb micro­wave energy. As the microwave energy at a frequeny of 2450 Megahertzenters the food, the molecules align themselves with the energy. Because the microwave are changing polarity every half cycle, the food mole-
However, cooking by microwave energy only, produces no browning or searing (unless cooking a roast of sufficient thickness). This microwave oven is, therefore, equipped with a sheath heater to provide browning of the food. The combination of the heater plus high-speed circu-
lation of air by a circulating fan around the food pro­vides fast cooking and
browning
of foods conventionally with or without the addition of micro­wave energy.
SPECIFICATION
ITEM
Power Requirements
Power Output
Convection Power Output
Case Dimensions
Cooking Cavity Dimensions
Control Complement
Set Weight
DESCRIPTION
240 Volts 6 Amperes (Microwave)
6.7 Amperes (Convection) 50 Hertz Single phase, 3 wire earthed
700 watts normal of RF microwave energy (2 liter water lod) Operating frequency of 2450MHz
1500 Watts Width 627 mm
Height 408 mm including foot Depth 505 mm
Width 395 mm Height 256 mm
Depth 422 mm
Micrwave Power for Variable Cooking
Repetition Rate;
HIGH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Full power throughout the cooking time
MED.HIGH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . approx. 70% of Full Power
MEDIUM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . approx. 50% of Full Power
MED.LOW(DEFROST) . . . . . . . . . . . . . . . . . . . . . . . . approx. 30% of Full Power
LOW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . approx. 10% of Full Power
Convection Temperature Control Range;
40 to 250 “C Auto Start Cooking Comp Defrost Cooking Convection Cooking
Instant Cooking Sensor Cooking (R-8570 only) Compu Cooking (R-8570 only)
Approx. 34 kg
Page 5
R-8470 R -8570
OPERATING INSTRUCTIONS
R-8470
R-8470
3-m
@ INDICATORS @I COMPU DEFROST SYMBOL @ CONVECTION FAN SYMBOL
Touch to select Compu Defrost setting.
INSTANT COOKTM PAD
Touch to cook for 1 minute at HIGH or in­crease bv 1 minute multioles durina variable
Il/~h
cooking.
NUMBER AND TEMPERATURE PAD
Touch to enter cookina times. clock time or convection temperature.
CONVECTION COOKING FUNCTION PADS
Touch to cook for each function.
VARIABLE COOKING CONTROL PADS
Touch to select microwave power setting If not touched, HIGH is automatically selected.
TIMER/HOLD PAD
Touch to set minute timer or HOLD the setting.
AUTO START/CLOCK PAD
Touch to set clock or auto start time
STOP/CLEAR PAD
Touch to erase during programming. Touch once to stop operation of oven during cooking; touch twice to cancel
FT@-+= “MEL PEtart oven.
R-8570
pucO~~~~~~~~ FAN SYMBOL
n
1 ”
CONVECTION FAN SYMBOL
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CON” MED Low RAM MO AUTO stm mm. aimi cm -
COMPU DEFROSTTM SYMBOL
This symbol flashes and varies in size whenever the compu defrost power IS on.
LIGHTED DIGITAL DISPLAY
Shows readout of cooking time. cooking instruction or time of day.
INDICATORS
.- CONYECTlON
, not _
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LOW MIX
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CONVECTION COOKING FUNCTION PADS
Touch to cook with each function.
SENSOR COOK PAD
Touch to select Sensor Cook settings.
COMPU COoKTM PAD
Touch to select CompuCook settings.
INSTANT COOK PAD
Touch to cook for 1 minute at HIGH or Increase by 1 minute multi­ples during variable cooking.
COMPU DEFROSTTM PAD
Touch to select CompuDefrost settings.
NUMBER AND TEMPERATURE PADS
Touch to enter cooking times, clock time or convection tem­perature.
VARIABLE COOKING CONTROL/FOOD DONENESS SETTING PADS
Touch to select mIcrowave power setting. If not touched, HIGH IS automatlcallv selected. Touch to select food doneness setting for CompuCook. If not touched, Med Done IS automatlcallv selected.
TIMER/HOLD PAD
Touch to set the minute timer or hold (pause) the cooklng cycle during a multlple sequence programme.
AUTO START/CLOCK PAD
Touch to set clock or auto start time.
START PAD
Touch to start oven.
STOP/CLEAR PAD
Touch to erase during programnxng. Touch once to stop operanon of oven during cooking; touch twice to cancel cooking program.
3
Page 6
OPERATION
DESCRIPTION OF OPERATING SEQUENCE
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The
following is a description of component functions
during oven operation.
OFF CONDITION
Closing the
door activates
both door interlock
switches: upper latch switch and lower latch switch.
(In this condition,
the monitor switch contacts are
opened
.)
The
stop switch is activated (contacts closed) by the
latch head, when the door is closed. When oven is plugged in, the 240 volts A.C. is supplied to the relay unit. (Figure O-l).
I, The
display will show flashing
“88:88”.
To set any program or set the clock, you must first touch the STOP/CLEAR (or STOP/CANCEL) pad. The display will clear,
and
I:00
will appear and
count up every minute.
Note: When the door is opened, the oven lamp comes
on.
2. A signal is input to the control unit, energizing the coil of shut-off relay (RY6).
RY6 contacts close, completing a circuit to the damper motor. The damper motor now operates moving the damper to the open position, thereby closing the contacts of the damper switch inputs a signal to the control unit. The coil of relay RY6 is de-energized, opening its contacts, thereby turning off the damper motor.
COOKING CONDITION
HIGH COOKING
Program desired cooking time and Variable Cooking Control by touching the NUMBER pads and the HIGH pad of the Variable Cooking Control. When the COOK
(or START) pad is touched, the following operations
occur:
1. The contacts of relays are closed and components connected to the relays are turned on as follows.
(For details, refer to Figure O-2)
RELAY CONNECTED COMPONENTS
RY-1 power transformer RY-2
oven lamp/turntable motor
RY-3
convection motor
Fly-4
heating element
RY-5
fan motor
RY-6
damper motor
2. The 240 volts A.C. is supplied to the primary wind-
ing of the power transformer and is converted
to
about 3 volts A.C. output on the filament winding, and approximately 2200 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 channeled through the waveguide into the cavity
feed-box, and then into the cavity where the food
is placed to be cooked.
5.
6.
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.
When the door is opened during a cook cycle,
monitor switch, stop switch, upper latch switch are activated with the following results. The circuits to the turntable motor, the cooling fan motor, and the
high voltage components are deenergized, the oven lamp remains on,
and the digital readout displays
the time still remaining in the cook cycle when the
door was opened.
7.
The monitor switch is electrically monitoring the
operation of the upper latch switch and is mechan­ically associated with the door so that it will func­tion in the following sequence. (1) When the door opens from a closed position,
the upper latch switch opens their contacts, and then the monitor switch contacts close.
(2) When the door is closed from the open posi-
tion, the monitor switch contacts first open, and then the contacts of the upper latch switch close.
If
the upper latch switch failes with their contacts
closed when the door is opened, the closing of the
monitor switch contacts will form a short circuit through the monitor fuse, upper latch switch , causing the monitor fuse to blow.
MED.HIGH, MEDIUM, MED.LOW(DEFROST),
LOW
COOKING
When the Variable Cooking is programed, the 240 A.C. voltage
is supplied
to the power transformer intermittently through the contacts of the relay which is operated by the control unit within a 32 second time base. The microwave power operation is as follows:
VARI-MODE
ON TIME OFF TIME
HIGH
32 sec.
0 sec.
(approx. 100% power)
MED.HIGH
24 sec.
8 sec.
(approx. 70% power) MEDIUM
18 sec.
14 sec.
(approx. 50% power) MED.LOW( DEFROST) 12 sec.
20 sec.
(approx. 30% power) LOW
6 sec. 26 sec.
(approx. 10% power)
Note: The ON/OFF time ratio does not correspond
with the percentage of microwave power, be­cause approx. 2 seconds are needed for heating of the magnetron filament.
CONVECTION COOKING CONDITION
PREHEATING CONDITION
Program desired convection temperature by touching the CONVECTION pad and the temp. pad. When the START pad is touched, the following oper­ations occur:
4
Page 7
R -8470 R-8570
1.
2.
3
The coil of shut-off relays (RY2, RY3 and RY5) are
energized, the oven
lamp, cooking fan motor,
turntable motor and convection motor are turned
on.
The coil of relay (RY6) is energized by the control
unit. The damper is moved to the closed position, opening the damper switch contacts.
The opening of the damper switch contacts sends
a signal to the LSI on the control unit
de-energizing the relay (RY6) and opening the circuit to the damper motor. The coil of heater relay (RY4) is energized by the
control unit and the mains supply voltage is added
to the heating element.
When the oven temperature reaches the selected
preheat temperature, the following operations oc-
cur:
4-1.
4-2.
The heater relay is de-energized by the con­trol unit temperature circuit and thermistor,
opening the circuit to the heating element.
The oven will continue to function for
15
minutes, turning the heater on and off, as needed to maintain the selected preheat
temperature. The oven will shut-down completely after
15 minutes.
CONVECTION COOKING CONDITION
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. Program desired cooking time and convection temper-
ature by touching the NUMBER pad, CONVECTION
pad and Temperature pad.
When the START pad is touched, the following oper-
ations occur: I.
2.
3.
4.
5.
The numbers of the digital readout start the count
down to zero. The oven lamps, turntable motor, cooking fan mo­tor and convection motor are energized.
Heater relay (RY4) is energized (if the cavity tem-
perature is lower than the selected temperature)
and the mains supply voltage is added to the
heating element to return to the selected cooking temperature.
Upon completion of the cooking time, the audible signal will sound, and oven lamps, turntable motor, cooking fan motor and convection motor are de-energized. At the
end.of
the convection cycle,
if the cavity air temperature is above 120
OC,
the circuit to RY5 will be maintained (by the thermistor circuit) to continue operation of the cooling fan motor until the temperature drops below 100
OC,
at which time the relay will be de-energized, turn-
ing off the fan motor. Relay RY3 will however,
open as soon sa the convection cycle has ended,
turning off the convection fan motor. This will now
cool and allow the damper door to open. At the end of the convection cook cycle, shut-off relay (RY6) is energized turning on the damper motor. The damper is returned to the open position,
closing the damper switch contacts which send a signal to the control unit, de-energizing shut-off relay (RY6).
AUTOMATIC MIX COOKING CONDITION
Program desired cooking time and temperature by
touching the number pads and the LOW MIX/BAKE
or HIGH MIX/ROAST pad
When the START pad is touched, the following oper-
ations occur:
1.
2.
3.
4.
5.
6.
The numbers of the digital readout start the count down to zero. The shut-off relay (RY2, RY3 and RY5) are
ener-
gized, turning on the oven lamps, turntable motor, and cooling fan motor.
The shut-off relay (RY6) is energized.
The damper door is closed from the open position.
The heater relay (RY4) is energized, adding the
mains supply voltage to the heating element. Now, the oven is in the convection cooking con­dition. When the oven temperature reaches the selected temperature, the following operations occur: 6-l. The power supply voltages is added to the
heating element and power transformer al­ternately.
6-2. The heating element operates through the
heater relay (RY4) contacts and the power transformer operates through the cook relay
(RYI ) contacts.
6-3. These are operated by the control unit to
supply alternately within a 32 second time base, convection heat and microwave en-
ergy.
The relationship between the convection and micro­wave power operations are as follows.
Note: The ON and OFF time ratio does not correspond
with the percentage of microwave power, be-
cause approx. 2 seconds are needed for heating
of the magnetron filament.
MICROWAVE
POWER
(MICR0.l
-
Appmx.
10%
I
I
I
I
,
‘ON
I I
CONVECTION TEMPERATURE
OFF
-
184vc
LOWMIX’
BAKE
lCONVEC.1
I
32 UC.
I
I-
I
HIGH MIX
-­ROAST
MICROWAVE
FOWER
- A~ox. 30%
CONVECTION TEMPERATURE
=
2oo”c
Note: During alternate Microwave/Convection opera-
tion, the convection heater is energized only if the cavity temperature drops below the set tem­perature.
5
Page 8
R-8470 R-8570
SENSOR COOKING CONDITION (R-8570
only)
Using the SENSOR COOK function, the foods are cooked without figuring time, power level or quantity. When the oven senses enough steam from the food, it
relays the information to its microprocessor which will
calculate the remaining cooking time and power level
needed for best results. When the food is cooked, water vapor is developed. The sensor “senses” the vapor and its resistance in-
creases gradually. When the resistance reaches the
value set according to the menu, supplementary cook-
ing is started. The time of supplementary cooking is determined by experiment with each food category and inputted into the LSI.
An example of how sensor works:
1. Broccoli at room temperature. Vapor is emitted very slowly.
2. Heat broccoli. Moisture ‘and humidity is emitted
rapidly. You can smell the aroma as it cooks.
3. Sensor detects moisture and humidity and calcu-
lates cooking time and variable power.
Cooking Sequence.
1. Touch SENSOR COOK pad.
NOTE:The oven should not be operated on SEN-
SOR COOK immediately after plugging in the unit. Wait five minutes before cooking on SENSOR COOK.
2. Select desired Sensor setting.
3. Touch START pad.
The coil of shut-off relay (RY-1) is energized, the
oven light and cooling fan motor are turned on, but
the power transformer is not turned on.
4. After about 16 seconds, the cook relay (RY-2) is energized. The power transformer is turned on, microwave energy is produced and first stage is started. The 16 seconds is the cooling time required to re-
move any vapor from the oven cavity and sensor. NOTE: During this first stage, do not open the door
or touch STOP/CLEAR pad.
5.
When the sensor detects the vapor emitted from the food, the display switches over to the remaining cooking time and the timer counts down to zero. At this time, the door may be opened to stir food, turn it or season, etc.
6. When the timer reaches zero, an audible signal sounds.
The shut-offrelay and cook relay are de-energized and the power transformer, oven light, etc. are turned off.
7. Opening the door or touching the STOP/CLEAR pad, the time of day will reappear on the display and the oven will revert to an OFF condition.
COMPUCOOK (R-8570 only)
COMPUCOOK will automatically compute the oven
temperature, microwave power and cooking time for
baking, roasting and broiling. Set the
desired
program by
touching
the
COMPUCOOK pad, and number pad. Enter the weight by touching the Number pads When the START pad is touched, the following oper­ations occur:
1.2.The COOK indicator will light and the Convection Fan Symbol will rot ate.
The cooking time will appear on the display and start counting down to zero. The cooking time is adjusted automatically ac-
cording to the setting quantity or weight of food.
The shut-off relays (RY2, RY3, RY4 and RY5) are
energized, turning on the oven lamp, turntable motor, cooling fan motor and convection motor. The power supplay voltage is added to the heating element.
Now, the oven is in the convection cooking mode. When the oven temperature has reached the pro­grammed convection temperature, the oven goes
into the programmed cooking mode. At the end of the COMPUCOOK cycle, the damper
is returned to the open position and the oven will be off condition. The cooling fan will remain on until the oven has cooled.
3.
4.
5.
6.
COMPU DEFROST COOKING
The COMPU DEFROST key is a special function key to defrost meats and poultry faster and better.
COMPU DEFROST 1 to 5 automatically defrosts roast beef, etc. Each key has 3 defrost stages.
When the desired COMPU DEFROST number is
lected
and the food weight is entered by using
number pad’s, the oven will cook according to
special cooking sequence.
se-
the the
Page 9
R-8470 R-8570
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Page 10
R-8470
R
-8570
DESCRIPTION AND FUNCTION OF COMPONENTS
UPPER
AND
LOWER LATCH
SWITCHES
The upper and lower latch switches are activated by the latch heads on the door. When the door is opened, the switches interrupt the circuit to the power trans­former, etc. For detais, refer to Oven Schematic dia­gram. And the switches interrupt the circuit to the heating element for model which is provided the heating ele­ment. A cook cycle cannot take place until the door is firmly closed thereby activating both latch switches.
Fi
/+
k
UPPER
LATCH
normally closed. At this time the upper latch switch are in the OFF condition (contacts open) due to their being normally open contacts switches.
2. As the door goes to a closed position, the monitor switch contacts are first opened and then the upper
latch switch contacts close. (When opening the
door, each of these switches operate inversely.).
3. In the door is opened and the upper latch switch contacts fail to open, the fuse blows simultaneously with the closing of the monitor switch contacts.
CAUTION: BEFORE REPLACING A BLOWN FUSE,
TEST THE MONITOR SWITCH, UPPER
LATCH SWITCH FOR PROPER OPERA­TION. (REFER TO CHAPTER “TEST PRO­CEDURE”)
DOOR OPEN
MECHANISM
The door can be opened by grasping the door handle and pulling strong. When the door is pulled, the lower and upper latch
heads mounted in the door are raised up to release them from the latch hooks. The door can now be opened.
LATCH
SWITCH
.
Latch,Monitor
and
stop
Switch
MONITOR SWITCH The monitor switch is activated (the contacts opened) by the upper latch head on the door while the door is closed. This switch is intended to render the oven in­operative by means of blowing the fuse when the contacts of the upper latch switch falles to open when the door is opened. Functions:
1. When the door is opened, the monitor switch con-
tacts close (to ON condition) due to their being
Go
t
-
UPQER
LATCH
LOWER LATCH
HEAD
HEAD
Figure D-2. Door
Open
Mechanism
Page 11
R
-8470
R-8570
DAMPER OPEN-CLOSE MECHINISM
Usually, the damper is open position except during the
convection cooking.
Damper position is set automatically by damper motor, damper switch, motor cam and damper shaft. These components are operated according to the signal that judges the microwave cooking or convection cooking operation in the control unit.
Microwave Cooking:
Damper is in the open position, because a portion of cooking air is channeled through the cavity to remove steam and vapors given off from the heating foods.
It is then exhausted at the top of the oven cavity into a condensation compartment.
Convection Cooking:
Damper is in the closed position, so that no hot air will
be allowed to leak out the oven cavity.
Damper Operation
1. When power supply cord is plugged in:
l-l.
1-2.
1-3.
I-4.
l-5.
When power supply cord is plugged in, a sig-
nal is sensed in the control unit, and operates
the shut-off relay (RY6).
Contacts of shut-off relay (RY6) close, then
the damper motor is energized, opening the
damper door.
When damper is moved to the open position
by the damper cam damper switch is closed
(ON position). The signal of damper switch is re-sensed in the control unit and shut-off relay (RY6) is turned off. The 240 volts A.C. to the damper motor is stopped and the motor turns off.
2. When oven is microwave cooking: Damper is in the open position.
3. When oven is convection cooking:
3-l. 3-2.
3-3. 3-4.
Damper motor is energized by touching the convection, temperature and START pads. When damper is in the closed position
(damper switch is OFF), its signal is sensed
by the control unit, and shut-off relay (RY6)
is de-energized. The damper is held in the closed position
during the convection cooking operation.
At the end of the convection cooking, the shut-off relay (RY6) is energized, and damper
is returned to the open position.
DAMPER
,,,i’
Al
DAMPER
DAMPER CAM
YAMPER
MOTOR
Figure
D-3.
Damper
9
Page 12
R-8470 R-8570
SERVICING
TROUBLESHOOTING GUIDE
When troubleshooting the microwave oven, it is
IMPORTANT: If then oven becomes inoperative
be-
helpfull to follow the Sequence of Operation in
per-
cause of a blown monitor fuse in the
forming the checks. Many of the passible causes of
monitor switch and upper latch switch
trouble will require that a specific test be performed.
circuit, check the monitor switch and
These tests are given a procedure letter which will be
upper latch switch before
replaceing
found in the “Test Procedure”section.
the monitor fuse.
PROBLEM
POSSIBLE
CAUSE
j
TEST
PROCEDURE OR I
I
I
CORRECTION
I
I
OFF CONDITION
Home fuse blows when power
Shorted wire in power cord or wire har-
Replase cord or check wiring.
cord is plugged into wall recepta-
ness.
cle.
Monitor fuse blows when power
Shorted wire in power cord or wire har-
Replace power cord or check
cord is plugged into wall recepta-
ness.
and repair harness.
I
de.
Defective monitor switch.
Procedure F.
88:88 do not appear in display No power at outlet.
Check home fuse.
when power cord is first plugged
Blown monitor fuse.
Psocedure G.
into wall outlet.
Blown magnetron temp. fuse.
Psocedure H.
Open wire in power cord, wiring harness,
Replace or repair wiring. or wiring between control panel assembly units.
Defective control unit.
Procedure K. Defective relay unit.
Procedure J.
Display does not operate properly
Defective key unit.
Procedure L.
when
STOP/CLEAR
key is
touched. (Buzze should sound
defective control unit.
Procedure K.
and time of day should appear in
Defective relay unit
Procedure J.
display.)
Defective stop switch
Procedure E.
Oven lamp does not light with No power in home.
Check wall outlet.
I
door opened.
Open wire in power cord or wire harness. / poplace same or repair wir-
I I
Defective oven lamp.
Replace.
Defective upper latch switch.
Procedure E.
Open or loose wire connection to the Check wiring. above components.
Blow monitor fuse or magnetron temp. / Procedure G or H.
fuse.
10
Page 13
R-8470 R-8570
PROBLEM
POSSIBLE
CAUSE
TEST
PROCEDURE OR
CORRECTION
COOKING CONDITION
Oven lamp does not light in cook
Defective shut-off relay
(RYZ)
on relay Procedure J.
1
cycle.
unit.
(Does light when door is opened)
Defective control unit
Procedure K
i
Oven lamp does not light at all.
Burned out bulb.
Replace
Open wiring of oven lamp.
Check and repair wiring
/
Oven lamp lights, but turntable
Open or loose wiring to turntable motor.
Check and repair wiring
1
motor does not operate.
Defective turntable motor.
Replace
Turntable motor operates normally
Defective cooling fan motor.
Replace.
I
but cooling fan motor dies not
Defective shut-off relay (RY5) on relay Replace
operate
unit. Open or loose wiring to fan motor
Check and repair wiring
MICROWAVE
I
Oven des not go into a cook cycle when START pad is touched.
Oven seems to be operating but little or no heat is produced in
oven load. (Food
incompletely cooked or not cooked at all at end of cook cycle.)
I-
I-
Oven does into a cook cycle but extremely
uneven
heating is
produced in oven load(food). Oven does not cook properly
when programed for MEDIUM etc. cooking powers.
(Operates properly on HIGH)
Oven does not cook properly when programed in COMPU DE­FROST cooking mode
Upper and/or lower latch switches
defec-
Procedure E.
tive or out of adjustment. Defective cook relay (RYI ) on relay unit.
Procedure J.
Defective control unit.
(
Procedure K.
Defective key unit.
Procedure L.
Open or loose wiring to above compo-
Check and repair wiring
nents.
~~
Defective magnetron.
Procedure A.
Defective cook relay
(RYI )
on relay unit.
Procedure J.
Defective power transformer.
Procedure B.
Defective rectifier.
Procedure C.
Defective high voltage capacitor.
Procedure D.
Defective control unit.
Procedure K.
Open or loose wiring to above compo-
Check and repair wiring nents. Low voltage. Dirty oven cavity.
Turntable motor does not operate. Refer to proceding turntable
motor problem.
Defective control unit.
Procedure K. Defective key unit.
Procedure L. Open or loose wiring to above compo-
Check and repair wiring nents.
Defective COMPU DEFROST function.
Refer to COMPU DEFROST
section on operation manual
1
and check control unit.
11
Page 14
PROBLEM
POSSIBLE
CAUSE
TEST PROCEDURE OR
\
CORRECTION
1
CONVECTION
I
CONV indicator light but oven Defective key unit.
i
Procedure L
does not go into a cook cycle Defective thermistor.
Porcedure N
when START pad is touched.
Open wiring in circuit to above compo- Check and repair wiring.
/
nents.
CONV indicator lights, but heating
Defective heating element.
Procedure I
element does not heat.
Defective heater relay(RY4) on relay unit.
Porcedure J
Defective control unit.
Procedure K
i
Open or loose wire connection
to the Check and repair wiring.
above components
Temperature in the oven cavity is
Defective heating element.
Procedure I
1
lower or higher than preset,
Defective control unit.
Porcedure K
Defective convection mortor.
Replace motor.
Defective thermistor.
Procedure N
Defective cooling fan motor.
Replace
Defective dumper motor
Procedure 0
Defective drive mechanism of convection Check.
I
fan.
I
SENSOR (R-8570)
Oven is in the sensor cooking AH sensor open and/or short. condition but AH sensor does not
Defective control unit.
Procedure M Procedure K
- <-
end stage 1 or does not stop
Open or loose wire connection
to the Check and reapir wiring.
cooking cycle.
above components.
12
Page 15
R-8470 R-8570
TEST
PROCEDURES
-PROCEDURE LETTER
COMPONENT
TEST
A
MAGNETRON ASSEMBLY
TEST
DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPO­NENTS OR WIRING.
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.
Power output of the magnetron can be measured by performing a water temperature rise test. This test should only be used if above rests do not indicate a faulty magnetron and there is no defect in the following components or wiring: rectifier, high voltage capacitor, heater transformer and power transformer.
MICROWAVE OUTPUT
POWER
Microwav,e output power from the magnetron can be measured by way of substitution, i.e. it can
be measured by using water load how much it can be absorbed by the water load. To measure the microwave output power in the microwave oven, the relation of calorie and watt is used. When P(W) heating works for t(second), approximately P x
t/4.2
calorie is generated. On the
other hand, if the temperature of the water with V(ml) rises AT (
“C)
during this microwave
heating period, the calorie of the water is V x AT. The formular is as follows;
P x t / 4.2 = V x AT P (W) = 4.2 x V x AT / t
Our condition for the water load is as follows:
Water load . . .
2000 ml, Heating time
.
..I20
seconds (2 minutes)
P=7Ox
AT
Measuring method;
1. Put the water load of two (2) litres on the
center
of the oven shelf. The water load should be arranged in two (2) Pyrex beakers, the size of which is one (1) litre, and be placed at right and left, side by side, on the oven shelf.
2. Measure the temperature of water before heating and also after heating during two minutes by microwave, and calculate the temperature rise.
The temperature rise should be the average
of temperature differences measured in each beaker.
3. The output power should be calculated as follows. In case the measuring result is not satis­factory, execute the measurement several times and judge the result from the synthetic point of view. Microwave output power should be within
&--I
5% of the nominal one.
Calculation of output power; Microwave output power . ..P (W) = 70 x AT ( “C)
AT = ( ATL + ATR) / 2 : average temperature rise ATL = (TL2 -
TLI),
ATR = (TR2 -
TRI)
TL2 : water temperature after heating in left beaker
TLI
: water temperature before heating in left beaker TR2 : water temperature after heating in right beaker
TRI : water temperature before heating in right beaker
Measuring condition; As the microwave output is affected by several conditions, the measurement should be made carefully with following attentions.
1. Initial temperature of salt water should be 20 + 1
“C.
(The salt water should be contained bon (1) percent of salt.) Well and quickly stir the water and the temperature measurement should be done immediately after heating.
2. The graduation of thermometer should be scaled by 0.1 “C at minimum and an accurate mer­cury thermometer is recommended.
13
Page 16
TEST PROCEDURES
(CONT’D)
-~
PROCEDURE
LETTER
COMPONENT
TEST
3. Water container should be one (1) litre beaker made of Pyrex glass and its diameter approxi­mately 12 cm.
4. Room temperature should be around 20
“C.
5. Power supply voltage should be specification voltage.
B
POWER
TRANSFORMER
TEST
DISCHARGE THE HIGH VOLTAGE
CAPACITAOR
BEFORE TOUCHING ANY OVEN COMPO-
NENTS OR WIRING. 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.
(HIGH VOLTAGES ARE PRESENT TO HIGH VOLTAGE TERMINAL, SO DO NOT ATTEMPT TO
MEASURE THE FILAMENT AND HIGH VOLTAGE.)
C
SILICON
RECTIFIER TEST
DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPO­NENTS OR WIRING.
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 orobablv defective and should be replaced.
HIGH VOLTAGE CAPACITOR
TEST
DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPO-
NENTS OR WIRING.
If the capacitor is open, no high voltage will be available to the magnetron. Disconnect input leads and check for 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 the ohmmeter to see if it is short circuited
between the terminals. If it is short circuited, replace the capacitor.
E
SWITCH
TEST
Isolate the switch and check the connection by using the ohmmeter accord ing to the following table.
If improper operation is indicated, make the necessary switch adjustment or replacement.
Table: Switch Connection
Connection
Common Terminal-Normally Open Terminal
Common Terminal-Normally Close Terminal
(COM)
(NO)
(COM)
(NC)
Operation
Open circuit
Close circuit
I
Plunger released
i
Plunger pushed
Closed circuit
Open circuit
I
F
MONITOR SWITCH
TEST
Before performing this test, make sure that the upper latch switch is operating properly referring to the above Switch Test Procedure. Check the monitor switch operation by using the ohmmeter as following figure. When the door is open, the meter should indicate a closed circuit. When the monitor switch lever of the upper latch hook is pushed by a screw driver through the upper latch hole on the front plate of the oven cavity 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, replace the defective switch.
14
Page 17
R-8470
R
-8570
PROCEDURE
LETTER
COMPONENT
TEST
/
4JPPER
.
LATCH
ITOR
CH
MONITOR SWITCH LEVER
G
BLOWN
MONITOR
FUSE
If the monitor fuse in the primary-secondary-monitor switch circuit is blown when the door is opened, check the primary and secondary interlock switches and monitor switch according to the Test Procedure of those switches, before replacing the blown monitor fuse.
If the monitor fuse is blown by improper switch operation, adjust or replace the defective switch and monitor fuse at the same time.
Replace just the monitor fuse if the switches operate normally. CAUTION; REPLACEMENT FUSE MUST BE THE LISTED FUSE IN PARTS LIST.
H
TEMP.
FUSE TEST
A continuity check across the temp. fuse terminal should indicate a closed circuit. If the temperature of the magnetron reaches 115
OC, thne
temp. fuse opens. If the temp. fuse has opened, replace the fuse. An open temp. fuse indicates overheating of the magnetron assembly. Check for restricted air flow to the magnetron through the opening in the chassis, especially the cooling duct.
I
HEATING ELEMENT
TEST
Make sure the heating element is fully cooled and test as follows; a. Disconnect wire leads and measure the resistance with an ohmmeter. On the R x 1 scale, the
resistance between the heating element terminals should be approximately 38.4 ohms.
b. Disconnect wire leads and measure the insulation resistance with 500V - 1 OOM II insulation
-<
resistance meter.
The insulation resistance between heating element terminal and cavity should be more than
0.5M
Q.
15
Page 18
R-8470
R
-8570
TEST
PROCEDURES (CONT’D)
PROCEDURE
LETTER
COMPONENT
TEST
J
RELAY
UNIT
TEST
The relay unit consists of circuits including the shut-off relays, buzzer, transformer, etc.
Plug power cord into wall receptacle “88888” will be flashing in the display. Remove the outer case and check voltage between Pin Nos.
1 and 3 of the
12-pin
connector
(A) on the relay unit with an A.C. voltmeter. The meter should indicate 240 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 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
RYl
(COOK) RY2 RY3 RY4 (HEATER) RY5 RY6
OPERATIONAL
VOLTAGE
Approx. 14 V.D.C. Approx. 14 V.D.C. Approx. 14 V.D.C. Approx. 14 V.D.C. Approx. 14 V.D.C. Approx. 14 V.D.C.
CONNECTED COMPONENTS
Power transformer Oven lamp/Turntable motor Convection motor Heating element Cooling fan motor Damper motor
K
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 di-
vided into three units Control Unit, Key Unit and Relay Unit and troubleshooting by unit re-
placement is described according to the symptoms indicated.
1. Key Unit.
The following symptoms indicate a defective key unit. Replace the key un it.
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.
2. Control Unit
The following symptoms indicate a defective control unit. Replace the control unit.
2-l 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
asignal.
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 when it lights-up.
c) Only one indicator does not light up. 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 troubles 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.
Note: When a defective one or more of three components, the Control Unit, Key Unit or Relay
Unit are replaced, the defective part or parts must be properly packed for return in the shipping carton, with its cushion material, in which the new replacement part was shipped to you.
16
Page 19
R-8470 R-8570
TEST
PROCEDURES (CONT’D)
-
PROCEDURE
LETTER
L
COMPONENT
TEST
KEY UNIT
TEST
If the indicator does not respond to touching a key Pad use the following matrix and place a
jumper wire between the proper pin connections with the cable connector disconnected from the
control unit.
If the indicator responds and oven goes into operation, the key unit was faulty. If there is no response, replace the control unit.
1
KEY UNIT
j
4:R-B!noW
1
M
AH
SENSOR TEST
Checking the initial
sensor
cooking condition
(1) The oven should be plugged in at least five minutes
befor
sensor cooking.
(2) Room temperature should not exceed 35
“C.
(3) The unit should not be installed in any area where heart and steam are generated. The unit
should not be installed, for example, next to a conventional surface unit. Refer to the “INSTALLATION Instruction”.
(4) Exhaust vents are providend on the back of the unit for proper cooling and air flow in the
cavity.To permit adequate ventilation,
be sure to install so as not to block these vents.
There should be some space for air circuration.
(5) Be sure the exterior of the cooking container and the interior of the oven arer dry. Wipe
off any moisture with a dry cloth or paper towel.
(6) The Sensor works with food at normal storage temperature.For example, chicken pieces
would be at refrigerator temperature and canned soup at room temperature. (7) Foods weighing less than 3 ounces should be cooked by time and vaiper power. (8) Avoid using aerosol sprays or cleaning solvents near the oven while using Sensor settings.
The sensor will detect the vapor given of by the spray and turn off
befor
food is propary
cooked. (9) After 30 minutes it the sensor has not detected the vapor of the food, ERROR will appear
and the oven will shut off. When cooking bacon, the sensor must detect the vapor within
1-l /2 minutes before ERROR appeares and oven shuts off.
Water
load
cooking test
Make sure the oven has been plugged in at least five minutes before checking sensor cook op-
eration. The cabinet should be installed and screws tightened.
(1) Fill approximately 200 milliliters (7.2 oz) of tap water in a 1000 milliliter measuring cup. (2) Place the container on the center of tray in the oven cavity. (3) Close the door. (4) Touch SENSOR COOK pad and number pad 1 .Now, the oven is in the sensor cooking
condition and AS-l will appear in the display.
(5) Touch Start pad.The oven will operate for the first 16 seconds, without generating micro-
wave energy.
When the AH sensor is defective (open or short), ERROR will appear in the display after 16 seconds cooling time.
If ERROR appears check sensor wire connections and/or AH sensor. NOTE: ERROR will appear if the door is opend or STOP/CLEAR pad is touched during first
stage of sensor cooking.
17
Page 20
R-8470 R-8570
TEST
PROCEDURES (CONT’D)
PROCEDURE
LETTER
COMPONENT
TEST
(6) After approximately 16 seconds, microwave energy is produced,oven should turn off when
water is boiling (bubling).
If the oven dose not turn off, replace the AH sensor or check the control unit, refer to expla­nation below:
TESTING METHOD FOR
AH SENSOR
AND/OR CONTROL UNIT
To determine if the sensor is defective, the simplest method is to replace it with a new re­placement sensor.
(1) Disconnect oven from power supply and remove outer case. (2) Discharge the high voltage capacitor. (3) Remove the AH sensor. (4) Install the new AH sensor. (5) Re-install the outer case. (6) Reconnect the oven to the power supply andcheck the sensor cook operation proceed as
follows: 6-l. Touch SENSOR COOK pad and number 1 pad.
6-2. Touch Start pad. The contorol panel is in the automatic Sensor operation. 6-3. The oven will turn off automatically when the water is boiling (bubling).
N
If new sensor dose not operate propaly, the problem is with the contorol unit.
THERMISTOR
TEST
Disconnect the connector-E from the control unit. Measure the resistance of the thermistor with an ohmmeter. Connect the ohmmeter leads to Pin No’s E-l and E-2.
Room Temp.
Resistance
68 “F(20
“C) -
86 “F(30
“C) 1
Approx. 350 f2 - 155k
n
If the meter does not indicate above resistance, replace the thermistor.
0
DAMPER MOTOR
TEST
When the power cord is plugged into the wall receptacle, the 240 volts A.C. is supplied to the damper motor and the motor operates until the damper is opened and the damper switch closes. Then the damper motor stops operation.
If the damper motor does not operate, check for input voltage by A.C. volt-meter at the motor.
1. Disconnect the power cord from the wall receptacle.
2. Disconnect the wire loads of motor and connect the meter leads to the wire leads of main wire harness.
3. Reconnect the power cord into the wall receptacle.
.-
If 240 volts A.C. is. indicated at the wire leads, replace the motor. Not indicated, check the wire harness and the relay unit.
-
P
DAMPER SWITCH
TEST
Disconnect the wire leads from the switch terminals and connect the ohmmeter leads to the
common (COM and normaly open (NO) terminal of the switch.
1. When switch actuator is pushed by the damper motor cam, the meter should indicate a closed circuit.
2. When the power cord is plugged into the wall receptacle, the damper motor operates and damper cam rotates. The switch
actuater
is released and meter sould indicate an open circuit.
If improper operation is indicated, replace the damper switch.
18
Page 21
R-8470 R-8570
TEST
PROCEDURES (CONT’D)
PROCEDURE
LETTER
COMPONENT
TEST
a
CHECKING TEMPERATURE IN
THE
CONVECTION MODE
It is difficult to measure the exact temperature in the convection oven. An accurate thermocouple
type temperature meter must be used.
A low priced bi-metal type thermometer is not reliable or
accurate.
The temperature should be checked approximately 5 minutes after the preheat temperature is
reached (audible signal sounds four times). The temperature experienced may be approximately 20 “C 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 ( 240 ) 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%.
19
Page 22
R-8470 R-8570
TOUCH CONTROL PANEL ASSEMBLY
OUTLINE OF TOUCH CONTROL PANEL
The touch control section consists of the following
units as shown in the block diagram. (1) Control Unit (2) Key Unit (3) Relay Unit
Exchange of signals between each unit is indicated by
the arrows in the block diagram. The principal func-
tions of these units and the signal communicated among them are explained below.
Relay
Unit
Relay unit consists of six relays (RYI -RY6), power
source circuit and buzzer circuit.
Key Unit
The key unit is composed of a matrix, signals generated
in the LSI are sent to the key unit through
E7,E8,
El 1 -El 3and El 5-E17. When a key pad is touched, a signal is completed through the key unit and passed back to the LSI through
AN4-AN7
to perform the function that was
requested.
Control Unit
Control unit consists of LSI, power source circuit, synchronizing signal circuit, ACL circuit, buzzer circuit, temperature measurement circuit, absolute humidity sensor circuit and indicator circuit.
1)
LSI
This LSI controls the temperature measurement signal, AH sensor signal,key strobe signal relay driving signal for oven function and indicator sig­nal.
2)
3)
4)
5)
6)
7)
8)
9)
Power
Source
Circuit
This circuit generates voltage necessary in the
control unit. Symbol Voltage Application
VC
-5v
LSI
(ICI), ACL circuit and tem-
perature measurement circuit
Et
VP
-15v Buzzzer circuit and IC2
+0.5v
IC2 (R-8570 only)
-34v Fluorescent display tube : Grid and anode voltage
VFI
-25V Filament of fluorescent display tube
VF2
-28V
VFI - VF2 voltage
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.
ACL
Circuit
Cirucit to generate signals resetting the LSI to the initial state when power is supplied.
Buzzer
Circuit
The buzzer is responsive to signals from the LSI to emit noticing sounds (key touch sound and
completion sound).
Temperature
Measurement Circuit:
Oven
temp.
The temperature in the oven cavity is sensed by the thermistor. The variation of resistance according to sensed temperature is detected by the temperature meas-
urement circuit and the result applied to LSI. The result of detecting is given to LSI controlling the relay and display.
Absolute Humidity
Sensor
Circuit (R-8570
only)
The circuit detects absolute humidity of a food
which is under cooking, to allow its automatic
cooking.
Stop Switch
Go;w$h
to “tell” the LSI if the door is open or
Relay’Circuit
To drive the magnetron, heating element, fan mo­tor, convection motor,damper motor, turntable
motor and light the oven lamp.
10)
Indicator Circuit
Indicator element is a Fluorescent Display.
Basicalloy, a Fluorescent Display is triode having a cathode, a grid and an anode. Usually, the cathode
of a Fluorescent Display is directly heated and the filament serves as cathode. The Fluorescent Display 7-digits, 15-segments are
used for displaying figures.
20
Page 23
R
-8470
R
-8570
1
I
2
3
4
5
6
1
2
Figure T-l. Block Daigram
3
4
5
I I
6
21
Page 24
R-8470
R
-8.570
LSI (
1X2429)
The I/O
signa
I of the LSl(lX2429) is detailed in the following table.
DESCRIPTION OF LSI
PIN NO.
l-6
1
SIGNAL / EO-E5
I
I/O
j
OUT
Dinit selection sianal.
Refer to the touch control panel circuit about the relation between signals and digits. Normally, one pulse is output in every synchronized signal period, and input to the grid of the fluorescent display.
PIN NO. ) 7
1
SIGNAL j E6
I
I/O
1
OUT
Seqment data
signals.
Refer to the touch control panel circuit about the relation between signls and indicators. Normally, one pulse is output in every synchronized signal period, and input to the grid of the fluorescent display.
PIN NO. j 8
Segment data skmal.
Signal similar to E6.
Kev strobe siqnal.
1
SIGNAL / E7
I
I/O
(
OUT
Signal applied to touch-key section. A pulse signal is input to
AN4-AN7
terminal while one of G-2 line keys on key matrix is touched.
PIN NO. / 9
Segment data sianal.
Signal similar to E6.
1
SIGNAL / E8
I
I/O
j
OUT
Kev strobe siqnal.( R-8570 onlv)
Signal applied to touch-key section. A pulse signal is input to
AN4-AN7
terminal while one of G-3 line keys on key matrix is touched.
PIN NO. j
IO,11
Segment data siqnal.
Signal similar to E6.
SIGNAL /
E9,ElO
I
I/O
j
OUT
PIN NO. / 12
1
SIGNAL ( El1
I
I
I/O
j
OUT
Segment data siqnal.
Signal similar to E6.
Kev strobe siqnal.
Signal applied to touch-key section. A pulse signal is input to
AN4-AN7
terminal while one of G-4 line keys on key matrix is touched.
PIN NO. ) 13
Segment data siqnal.
Signal similar to
E6.
Kev strobe signal.
1
SIGNAL j El2
I
I/O
1
OUT
Signal applied to touch-key section. A pulse signal is input to
AN4-AN7
terminal while one of G-5 line keys on key matrix is touched.
PIN NO. / 14
1
SIGNAL
El3
I
I/O
/
OUT
Seqment data sknal.
Signal similar to E6.
Kev strobe siwal.
Signal applied to touch-key section. A pulse signal is input to
AN4-AN7
terminal while one of G-6 line keys on key matrix is touched,
22
Page 25
R-8470 R-8570
PIN NO. / 15
1
SIGNAL /El4
I
I/O
1 OUT
Seqment
data siqnal.
Signal similar to E6.
PIN NO. / 16
1
SIGNAL
El5
I
I/O
/
OUT
Seqment
data siqnal.
Signal similar to E6.
Key strobe
siqnal.
Signal applied to touch-key section. A pulse signal is input to
AN4-AN7
terminal while one of G-7 line keys on key matrix is touched.
PINNO. /
17
Seqment
data siqnal.
Signal similar to E6.
Kev strobe
siqnal.
1
SIGNAL j El6
I
I/O
(
OUT
Signal applied to touch-key section. A pulse signal is input to
AN4-AN7
terminal while one of G-8 line keys on key matrix is touched.
PIN NO. / 18
1
SIGNAL / El7
I
I/O
1
OUT
Seqment data
siqnal.
Signal similar to E6.
Kev strobe
siqnal.
Signal applied to touch-key section. A pulse signal is input to
AN4-AN7
terminal while one of G-9 line keys on key matrix is touched.
PIN NO.
19,20
1
SIGNAL 1
El8,E19
I
l/O
1
OUT
Seqment data
siqnal.
Signal similar to E6.
PIN NO.
/
21-24
1
SIGNAL /E20-
E23
I
I/O
1
OUT
R-8470: Terminal not used. Connected to GND.
R-8570:
Used for initial balancing of the bridge circuit(absolute himidity sensor).
PIN NO. / 25
1
SIGNAL 1 EX
I
I/O
1
IN
Internal
clock
oscillation frequency settinq input.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit with respect to X terminal.
PIN NO. /
,26
1
SIGNAL / X
I
l/O
/
OUT
tnternal
clock
oscillation frequency control output.
Output to control oscillation
inpout
of EX.
PIN NO. / 27
Auto clear terminal.
1
SIGNAL
/
RESET
I
I/O
IN
Signal is input to reset the LSI to the initial state when power is supplied. Temporarily set to “L” level the moment power is supplied, at this time the LSI is reset. Thereafter set at “H” level.
PIN NO.
1 28
Segment
data siqnal.
Signal similar to E6.
1
SIGNAL / SO E24
I
I/O
1
OUT
23
Page 26
q-8470 q-8570
PIN NO. 29
1
SIGNAL / SI E25
I
I/O
i
OUT
R-8470: Terminal not used. R-8570: Used for initial balancing of the bridge circuit(absolute himidity sensor).
PIN
NO. ( 30
1
SIGNAL (E26
I
I/O / OUT
Signal to sound buzzer.
A: Key touch sound.(0.12 sec.) B: Completion sound. (2.4 sec.) C: When the temperature of the oven cavity reaches the preset temperature in the preheating mode, or when the
preheating hold time (15 minutes) is elapsed. (1.2 sec. ON-l .2 sec. OFF repeat)
PIN NO. 31
1
SIGNAL / IRQ E27
I
I/O
1
IN
Signal synchronized
with commercial source frequencv(50Hz).
This is the basic timing for time processing of LSI.
PIN NO. / 32
1
SIGNAL 1 Vss
Power
source
voltage: -5V.
VC voltage of power source circuit input.
I
I/O
1
IN
PIN NO. / 33
1
SIGNAL / RO
Magnetron high-voltage circuit driving signal.
To turn on and off the cook relay.
I
l/O
/
OUT
In HIGH operation, the signals holds “L” level during microwave cooking and “H” level while not cooking. In other cooking modes (MED. HIGH, MED., MED. LOW, LOW) the signal turns to “H” level and “L” level in repetition according to the power level.
PIN NO. j 34
1
SIGNAL 1 RI
I
I/O
/
OUT
Oven lamp
and turntable motor driving signal.(Sauare Waveform:50Hz)
To turn on and off the control relay. The pulse signai(50Hz) is delivered to the control relay driving circuit and cook relay and heater relay control cir­cuit.
PIN NO. / 35
1
SIGNAL j R2
I
l/O
1
OUT
Heating element driving siqnal.
To turn on and off the heater relay. “L” level during convection cooking; “H” level otherwise. During convection cooking or mix cooking, the signal becomes “H” level when the temperature of the oven, cavity exceeds the predetermined temperature.
PIN NO. 1 36
1
SIGNAL ( R3
I
l/O
/
OUT
Cooling fan
motor driving signal.
To turn on and off the cooling fan motor relay.
“L” level during both microwave and convection cooking; “H” level
otherwise.
PIN NO. j 37
SIGNAL / R4
I
I/O
/
OUT
Convection motor driving signal.
To turn on and off the convection motor.
“L” level during CONVECTION or MIX COOK; “H” level otherwise.
24
Page 27
R-8470 R-8570
PIN NO.
1 38
SIGNAL / R5
Damper motor relav driving
signal.
To turn on and off the damper motor relay.
I
I/O
/
OUT
PIN NO. / 39
-Digit selection
signal.
Signal similar to EO.
SIGNAL j R6
I
I/O
/
OUT
PIN NO.1 40
1
SIGNAL 1 R7
I
I/O
j
IN
Input
signal
which communicates the damper open/close information to LSI.
Damper opened; “H” level signal. Damper closed; “L” level signal.
PIN NO.
/
41
1
SIGNAL / E37
I
I/O
Terminal to
change
functions according to the model.
Signal in accordace with the model in operation is applied to set up its function.
IN
PIN NO. / 42
1
SIGNAL / E36
I
I/O
/
IN
Input
signal
which communicates the door open/close information to
LSI.
Door closed; “H” level signal. Door opened;
“L” level signal.
PIN NO. / 43 Connected to VC.
1
SIGNAL /AVss
I
I/O
j
IN
PIN NO. / 44
1
SIGNAL 1 AVR-
Reference voltage input terminal.
A reference voltage applied to the A/D converter in the LSI. The reference voltage is generally maintained at -5V.
I
I/O
1
IN
PIN NO. / 45
1
SIGNAL
/
AVR+
I
I/O
IN
Reference voltage input terminal.
A reference voltage applied to the A/D converter in the LSI.
Connectd to GND.
PIN NO. 1 46 Connected to GND.
1
SIGNAL jAVcc
I
I/O
/
IN
PIN NO. ( 47
1
SIGNAL / AN7
I
l/O
/
IN
Signal
coming from touch
key.
When either one of G-l 3 line keys on key matrix is touched, a corresponding signal out of
E7,E8,Ell
-El 3 and
El
5-El7
will be input into AN7.
When no key is touched, the signal is held at “L” level.
PIN NO. / 48
1
SIGNAL / AN6
I
I/O
IN
Signal coming from touch
key.
When either one of G-12 line keys on key matrix is touched, a corresponding signal will be input into AN6.
PIN NO.
1 49
1
SIGNAL / AN5
I
I/O
1
IN
Signal coming from touch
kev.
When either one of G-l 1 line keys on key matrix is touched, a corresponding signal will be input into AN5.
PIN NO. / 50
1
SIGNAL j AN4
I
I/O
j
IN
Signal cominQ
from touch
key.
When either one of G-10 line keys on key matrix is touched, a corresponding signal will be input into AN4.
25
Page 28
R
-8470
R-8570
PIN NO. / 51
1
SIGNAL
/
AN3
I
I/O 1 IN
R-8470:
Terminal not used. No connection.
R-8570: Used for initial balancing of the bridge circuit (absolute humidity sensor).
This input is an analog input terminal from the AH sensor
circuitand
connected to the A/D converter built into the
LSI.
PIN NO. j 52 R-8470:
1
SIGNAL / AN2
I
I/O
IN
Terminal not used. No connection.
R-8570:
AH
sensor
input.
This input is an analog input terminal from the AH sensor circuit,
and connected to the A/D converter built into the
LSI.
PIN NO. / 53
1
SIGNAL j AN1
I
I/O
j
IN
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.
PIN NO. 1 54
1
SIGNAL
1
AN0
I
I/O
(
IN
Terminal not used. Connected to GND.
PIN NO. 55
1
SIGNAL / R8
Terminal not used. Connected to VC.
I
I/O
j
OUT
PIN NO. / 56-60
Terminal not used.
1
SIGNAL 1R9-RI3
I
I/O
IN
PIN NO. 1 61
1
SIGNAL i
RI4
Terminal not used. Connected to GND.
I
I/O
IN
PIN NO. j 62
1
SIGNAL /
RI5
I
I/O
IN
Terminal for manufacture test.
Normally connected to VC.
PIN NO. 1 63
1
SIGNAL ( NC
Terminal not used. Connected to GND.
I
I/O
/
NC
PIN NO. ) 64 Connected to GN D.
1
SIGNAL 1 Vcc
I
I/O
j
IN
26
Page 29
R
-8470
R-8570
ABSOLUTE HUMIDITY SENSOR CIRCUIT (R-8570
only)
(1)
Structure of Absolute Humidity
Sensor
The absolute humidity sensor includes two thermistors as shown in the illustration. One thermister is housed in the closed vessel filled with dry air while another in the open vessel. Each sensor is provided with the protective cover mode of metal mesh to be protected from the external airflow.
Internal Structure of
Sfmsor
(2
Operational Principle of Absolute Humidity Sensor
The figer below shows the basic structure of an absolute humidity sensor.
A bridge circuit is
fromed
by two thermistors and two resistors (RI and R2). The output of the bridge circuit is to be amplified by the operational amplifier.
Each thermister is supplied with a current to keep
itself heated at about 150 “C (302 “F) and the re­sultant heat is dissipated in the air and if the two thermistors are placed in different humidity condi­tions they
show different degrees
of heat
condutivity
leading to potential difference between them causing an output voltage from the bridge circuit, the intensity of which is increased as the absolute humidity of the air increases. Since the output is very minute, it will be amplified by the
operational amplifier.
*
Absolute humidity (g/m’ J
(3) Detector Circuite of Absolute Humidity
Sensor
Circuit
This detector circuit is used to detect the output voltage of the a absolute humidity circuit to allow the LSI to control the sensor cooking of the unit. When the unit is set in the sensor cooking mode, 16 seconds later the detector circuit starts to func­tion and the LSI observes the initial voltage availabel at its AN2 terminal. With this voltage given, the switches SW1 to SW5 in the LSI are
turned on in such a way as to change the resistance values in parallel with R50.
-1,
Changing the resistance values results in that there is the same potential at both F-3 terminal of the absolute humidity sensor and AN3 terminal of the
LSI.
The voltage of AN2 terminal will indicate
about -2.5V. This initial balancing is set up about
16 seconds after the unit is put in the Sensor Cooking mode. As the sensor cooking proceeds, the food is heated to generate moisture by which the resistance bal­ance of the bridge circuit is deviated to increase the voltage available at AN2 terminal of the LSI. Then the LSI observes that voltage at AN2 terminal and
compares it with its initial value, and when the comparison rate reaches the prest value (fixed for each menu to be cooked), the LSI causes the unit to stop the sensor cooking; thereafter, the unit gets in the next necessary operation automatically.
When the LSI starts to detect the initial voltage at
AN2 terminal 16 seconds after the unit has been put in the Sensor Cooking mode, if it is impossible to take a balance of the bridge circuit due to dis­connection of the absolute humidity sensor, ER-
ROR will reappear on the display and the cooking is stopped.
1 )Absolute humidity sensor circuit
c
n.rm.4e In
CIDwd “.,..I
s Thwm**(or
I”
opn “.SH,
. .
-51,
0
23
t
I
.p-r
22
i
,
wo-?I,
n
I
2)lnternal equivalent circuit of
I2
Top View
-)2 +I2
27
Page 30
A -8470
R
-8570
SERVICING
I,
Precautions for Handing Electronic
Components
This unit uses PMOS LSI in the integral part of the
circuits. When handing these parts, the following precautions should be strictly followed.
PMOS 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 charged in clothes, etc,and sometimes it is not fully protected by the
built-in protection circuit.
In order to protect PMOS LSI.
1) When storing and transporting, throughly wrap them in aluminum 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.
2. Servicing of
Touch
Control
Panel
We describe the procedures to permit servicing the touch control panel of the microwave oven and the cautions you must consider when doing so. To carry the servicing, power supply to the touch control panel is available either from the power line of the oven proper itself of from an external power source.
(1) Servicing the touch control
panel
with
power
supply
from the
oven proper:
CAUTION:
THE
HIGH VOLTAGE TRANSFORMER
OF
THE
MICROWAVE
OVEN IS STILL
ALIVE
TO GIVE
YOU
DANGER DURING
SER-
VICING.
Therefore, when checking the performance of the touch control panel,put the outer cabinet on the oven proper to keep you from touching the high voltage transformer, or unplug the primary terminal (connector) of the high volt­age transformer to turn it off; and the end of such connector shall be insulated with an in­sulating tape. After servicing, be sure to replace
the leads to their original locations.
A. On some models, the power supply cord be-
tween the touch control panel and the oven
proper is so short that they can’t be separated
from each other.
For those models, therefore, check and repair all the controls (with the sensor-related ones included) of the touch control panel while keeping it in contact with the oven proper.
3.
4.
B.
On some models, on the other hand, the power supply cord between the touch control panel and the oven proper is so long that they may
be separated from each other. For those mod­els, therefore, it is allowed 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 stop switch (on PWB) of the touch control panel
with a jumper, which brings about an opera-
tional state that is equivalent to that with the
oven door being closed.
As to the sensor-related controls of the touch
control panel, their checking is allowed if the
dummy resistor(s) whose resistance is equal to
that of those controls is used.
(2)
Servicing the touch control
panel
with
power supply from an external power
source:
Disconnect the touch control panel completely from the oven proper,and short both ends of the stop switch (on PWB) of the touch control
panel,which brings about such an operational
state that is equivalent that with the oven door
being closed. And connect an external power source to the power input terminal of the touch
control panel, and then it is allowed to check
and repair the controls of the touch control
panel;as
in the case of (1 )-B above, it is here
also possible to check the sensor-related con­trols of the touch control panel by using the
dummy resistor(s).
Serivicing
Tools
Tools required when serivicing the touch control panel assembly.
1) Soldering:
3ow
(To prevent leaking current, it is recommended to
use a soldering iron with grounding terminal.)
2) Oscilloscope: Single beam, frequency range: DC -
IOMHz
type or more ad-
vanced model.
3) Others:
Other tools
Other Precautions
1) When turning on the power source of the con-
trol unit, remove the aluminum foil applied for
preventing static electricity.
2) Connect the connectors of the indicator and
key units to the control unit taking care that the lead wires are not twisted.
3)
After aluminum foil is removed, take extra care
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, taking care that all connections are tight.
5) Be sure to use specified components where
high precision is required.
28
Page 31
R-8470 R-8570
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE
WARNING: TO AVOID POSSIBLE EXPOSURE TO
3. THE DOOR IS BENT OR WARPED.
MICROWAVE ENERGY;
4. THERE IS ANY DEFECTIVE PARTS IN THE
A.
B.
1.
::
4.
5.
BEFORE OPERATING THE OVEN
INTERLOCK, OVEN DOOR OR MICROWAVE
1. MAKE SURE THAT UNLATCHING THE DOOR
GENERATING AND TRANSMISSION AS-
SLOWLY IS ACCOMPANIED BY A CLICK IN-
SEMBLY.
DICATING ACTUATION OF THE MONITOR
5. THERE IS ANY OTHER VISIBLE DAMAGE TO
SWITCH AND LATCH SWITCH.
THE OVEN.
2. CHECK VISUALLY THE DOOR SEAL FOR
C. DO NOT OPERATE THE OVEN
ARCING AND DAMAGE.
1. WITHOUT THE RF GASKET.
DO NOT OPERATE THE OVEN UNTIL AFTER RE-
2. IF THE DOOR IS NOT CLOSED.
PAIR IF ANY OF THE FOLLOWING C ONDITIONS
CAUTION: DISCONNECT THE OVEN FROM THE
EXIST;
POWER SUPPLY BEFORE REMOV-
1. DOOR DOES NOT CLOSE FIRMLY AGAINST
ING OUTER CASE. DISCHARGE THE
THE FRONT OF APPLIANCE.
HIGH VOLTAGE CAPACITOR BE-
2. THERE IS A BROKEN DOOR HINGE OR
FORE TOUCHING ANY OVEN COM-
SUPPORT.
PONENTS OR WIRING.
POWER TRANSFORMER REMOVAL
Disconnect oven from power supply and remove
outer case.
3.
Discharge high voltage capacitor. Disconnect filament leads of transformer from the
magnetron.
4.
Disconnect wire leads from the transformer. Remove two (2) screws holding the transformer to
the cabinet base.
Re-install
5
1.
2.
1.
;:
1.
2.
3.
1.
2.
3.
4.
Rest the transformer on the base cabinet with its primary terminals toward. Insert the two edges of the transformer into two metal tabs of the base cabinet.
6.
Make sure the transformer is mounted correctly to the corners underneath those tabs After re-installing the transformer, secure the transformer with two screws to the cabinet base, one is with outertooth washer and the other is without outer-tooth washer.
Re-connect the wire leads (primary and high voltage) to the transformer and filament leads of transformer to the magnetron, referring to the “Pictorial Diagram”.
Re-install the outer case and check that the oven is operating properly.
SILICON RECTIFIER REMOVAL
Disconnect oven from power suppply and remove
4. Disconnect the rectifier from the capacitor.
outer case.
CAUTION: WHEN REPLACING THE SILICON
Discharge the high voltage capacitor.
RECTIFIER, THE GROUND SIDE TER-
Remove single (1) screw holding the rectifier to the
MINAL MUST BE SECURED FIRMLY
capacitor holder.
WITH A GROUNDING SCREW.
HIGH VOLTAGE CAPACITOR REMOVAL
Disconnect oven from power supply and remove
outer case.
Discharge the high voltage capacitor. Disconnect wire leads and rectifier from the
capacitor.
4. Remove single (1) screw holding the capacitor holder to the rear cabinet using a special screw-driver.
5. Remove the capacitor holder with capacitor and rectifier attached.
6. Remove the capacitor from the holder.
TURNTABLE MOTOR AND/OR COUPLING REMOVAL
Disconnect the oven from power supply. Remove single (1) screw holding the turntable
motor cover to the base cabinet and remove it.
Disconnect 2-pin connector from the turntable mo-
tor.
Remove the three (3) screws holding the turntable motor assembly to the oven cavity bottom and re­move it.
5. Remove the two (2) screws holding the turntable motor to the mounting plate.
6. The turntable motor is now free.
7. After removal of the turntable motor assembly, re-
move the ring and washer holding the turntable
coupling to the oven cavity bottom.
8. The turntable coupling is now free.
29
Page 32
R-8470 R-8570
MAGNETRON ASSEMBLY REMOVAL
I.
Disconnect oven from power supply and remove
6. Lower the magnetron assembly until the tube is
outer case.
clear of the waveguide.
2. Discharge the high voltage capacitor.
7. Remove single (1) screw holding the cooling duct
3. Disconnect wire leads from the magnetron
assem-
(B) to the magnetron assembly.
bly.
8. Remove the cooling duct (B) from the magnetron.
4. Release the tab which is provided on cooling duct
CAUTION:
WHEN REPLACING THE MAGNETRON,
(B) to hold cooling duct (A).
BE SURE THE R.F. GASKET IS IN
5. Carefully remove four (4) mounting screws holding
PLACE
AND
THE
MAGNETRON
the magnetron assembly to waveguide while sup-
MOUNTING SCREWS ARE TIGHTENED
porting the magnetron assembly from below.
SECURELY.
CONVECTION MOTOR REMOVAL
1. Disconnect oven from power supply and remove outer case.
2. Disharge the high voltage capacitor.
3. Disconnect wire leads from the convection motor.
4. Remove two (2) screw holding the convection motor assembly to the chassis support and waveguide flange.
The convection motor assembly is now free.
7. Remove the two (2) screw and nuts holding the mounting bracket to the motor
8. Remove the pin and pulley (B) from the motor shaft.
5. Remove the convection fan belt.
6. Lift up the convection motor assembly and remove it from the unit.
9. The convection motor is now free. Note: The motor mounting plate with the convection
motor should be installed in close contact with the waveguide flange. Otherwise, the revolution of the convection fan belt may be disrupted.
COOLING FAN
MOTOR REMOVAL
1. Disconnect oven from power supply and remove outer case.
7. Remove the duct (A) with the cooling fan motor attached from the unit.
2. Discharge the high voltage capacitor.
3. Disconnect wire leads from the cooling fan motor.
4. Remove screw holding the grounding wire to the oven cavity flange.
5. Remove four (4) screw holding the chassis support to rear cabinet, cooling duct (A), convection motor mounting plate and control panel back plate.
-
6. Release the tab which is provided on
(B) to hold the cooling duct (A).
cooling duct
The cooling fan motor assembly is now free.
8. Remove the fan blade from the cooling fan motor shaft by pulling the fan retainer clip.
9. Remove two (2) screws and nuts holding the cooling fan motor and grounding wire to the cool-
ing duct (A).
The cooling fan motor is now free.
1. Disconnect oven from power supply outer case.
and remove
2. Discharge the high voltage capacitor.
3. Remove the magnetron assembly, refer to “Magnetron Assembly Removal”.
4. Disconnect two (2) connectors for the damper motor from the relay unit.
5. Disconnect two (2) connectors for the stop switch from the relay unit.
DAPMER ASSEMBLY
6. Remove two (2) screw holding the damper duct to oven cavity right-side.
7. Remove single (1) screw holding the damper duct
to rear cabinet.
8. Remove two (2) screws holding the damper duct to top of the oven cavity.
9. Remove the damper assembly from the unit.
30
Page 33
R-8470 R-8570
\ 1.
2.
3.
4.
5.
6.
7.
8.
9.
HEATEING ELEMENT OR CONVECTION FAN REMOVAL
Disconnect oven from power supply and remove
outer case
Discharge high voltagecapacitor. Remove the cooling fan motor assembly and con-
vection motor assembly.
Disconnect wire leads from the heating element and
thermistor.
For R-8570, remove the five (5) screws holding the
sensor cover to the steam duct (A).
Remove single (1) screw holding the steam duct
(D), and remove it.
Remove three (3) screws holding the thermal pro­tection cover to thermal protection plate (A) and steam (A).
Release the tab holding the steam duct (C) and re­move the two (2) screws holding the steam duct
lO.Remove screw and nut holding the steam duct (B),
and remove it.
11 .Lift up thermal protection plate (D) and protection
sheet (D) together.
12.Remove six (6) screws and nuts holding the con­vection air gudie (A) , and slide it rightward for re-
move it.
The convection air guide (A) assembly is now free.
Replacement of individual components is as follows.
HEATING ELEMENT
1. Remove two (2) screws holding the convection air
guide (D) to convection air guide (A).
2. Remove two (2) screws holding the heating ele-
ment to convection air guide (A).
3. Remove the heating element.
(A) to the oven cavity flange. Remove the thermal protection plate (E).
CONVECTION FAN
Remove two (2) screws holding the air guide (A)
1. Remove the nut, washer and pin.
and remove it.
2. Pull the fan from the fan shaft.
CONTROL PANEL ASSEMBLY AND CONTROL UNIT REMOVAL
The complete control panel should be removed for re-
placement of components except the relay unit.
To remove the control panel, proceed as follows:
Replacement of individual component is as follows:
1.
2.
3.
4.
5.
6.
7.
8.
1.
2.
3.
4.
5.
6.
Disconnect oven from power supply and remove
outer case.
Discharge the high voltage capacitor. Disconnect the wire connectors and wire leads from
the relay unit.
Disconnect a connector from the control unit. Remove single (1) screw holding the control panel
back plate to the chassis support.
Remove the two (2) screws holding the bottom
edge of the back plate to the cabinet base.
Remove single (1) screw holding the back plate to
the oven cavity flange.
Lift up and pull the control panel forward.
Disconnect the wire connector of control unit from
the relay unit.
CONTROL UNIT AND KEY UNIT
1.
2
i:
5.
6.
Remove the four (4) screws holding the panel frame to the back plate. Separate the panel frame and back plate.
Remove the three (3) screws holding the control unit to the panel frame.
Lift up the control unit and disconnect the key connector from the control unit.
Now, the control unit and frame assembly are sep­arated.
UPPER/LOWER LATCH SWITCHES AND MONITOR SWITCH REMOVAL
Disconnect the oven from the power supply and
7.
remove the outer case.
Discharge the high voltage capacitor. Disconnect the wire leads from the switch (es).
1.
Remove the one (1) screw holding the upper latch hook to the oven caity front flange and remove the
one (1) screw holding the lower latch hook to the
2,
oven caity front flange.
Remove the latch hook from the flange by moving it downward.
3.
To remove the individual switch from the latch
4. hookes, push outward the two (2) retaining tabs holding the switch in place.
The switch is now free.
Re-install Re-install each latch switch and monitor switch its
place.
Re-connect the wire leads to each switch. Refer to chapter “Pictorial Diagram”. Secure the individual latch hook with the one (1) mounting screw to the oven cavity front flange.
Make sure that the monitor switch is operating properly. Refer to chapter “Test Procedure”, and the Adjustment procedure below.
31
Page 34
UPPER/LOWER LATCH SWITCHES AND MONITOR SWITCH ADJUSTMENT
If the upper and lower latch switches and monitor switch do not operate properly due to a mis-adjustment, the following adjustment should be made.
1. Loosen the one (1) screw holding the upper latch hook to the oven cavity front flange and the one (1) screw holding the lower latch hook to the same
flange.
2. With the door closed, adjust the lower latch hook by moving it back and forward and then adjust the upper latch hook by moving it back and forward, or up and down. In and out play of the door al­lowed by the upper and lower latch hooks should be less than 0.5 mm. The vertical position of the upper latch hook should be placed where the upper latch switch and monitor switch have activated with the door closed. Vertical adjustment of the lower
latch hook is not possible.
3. Secure the screws with washers firmly.
4. Now, make sure of the upper latch switch opera­tion. If the upper latch switch has not activated with the door closed, loose the one (1) screw holding
the upper latch hook to the oven cavity front flange
and adjust the upper latch hook position.
After the adjustment, make sure of the following
points:
1. The in and out play of the door remains less than
0.5 mm at latched position. First check the upper latch hook position, pushing and pulling the upper portion of door toward the oven face. Then check the lower latch hook position, pushing and pulling the lower portion of door toward the oven face.
Both results (plays of the door) should be less than
0.5mm.
2. The upper and lower latch switches interrupt the circuit before the door can be opened.
3. The monitor switch contacts close when the door
is opened.
4. Re-install the outer case and check for microwave
leakage around the door with an approved micro­wave survey meter. (Refer to Microwave Measure­ment Procedure.)
Figure C-l.
Latch
Switches Adjustment
32
Page 35
R-8470 R-8570
DOOR REPLACEMENT AND ADJUSTMENT
DOOR REPLACEMENT
1. Disconnect oven from power supply and remove outer case.
2. Holding the door, remove four (4) screws securing the door hinge to the oven cavity. The door assem­bly is nowfree from the oven cavity.
3. On re-installing new door assembly, secure the door assembly with the four (4) mounting screws to the oven cavity.
Make sure the door is parallel with the bottom line of the oven face plate and the latch heads pass through the latch holes correctly.
Note: After any service to the door, an approved
microwave survey meter should be used to as-
sure
compliance with proper
microwave rediation standard. (Refer to Microwave Measurement Procedure).
Note: If the Latch Heads Removal, “TORX T-20” or
“LHXTIX LR-3” Type screwdriver should be used.
TORX screw
HINGE MOUNTING PLATE
OOOR ASSEMBL
TORX SCREW (T-20)
LATCH HEADS
DOOR ADJUSTMENT When removing and/or loosening hinge such as in the case of a door replacement, the following adjustment criteria are taken. Door is adjusted to meet the fol-
lowing three conditions before tightening the hinge screws.
1. Adjust door latch heads at a position where they smoothly catch the latch hooks through the latch holes. Refer to primary and secondary interlock switches adjustment.
2. Deviation of the door alignment from the horizontal line of cavity face to be less than IOmm.
3. Door should be adjusted with its face depressed toward cavity face.
After hinge screws are tightened under foregoing con-
ditions, recheck 1 and 2.
Note: The door on a microwave oven is designed to
act as an electronic seal preventing the leakage of microwave energy from the oven cavity during :~t&co;~eycledo~rhis function does not require
be
airtight, moisture) condensationg-tight or light-tight. Therefore, the occasional appearance of moisture, light or the sensing of gentle air movement around the oven door is not abnormal and do not of themselves,
indicate a leakage of microwave energy from the oven cavity. If such were the case, your oven could not be equipped with a vent, the very
purpose of which is to exhaut the vapor-laden air from the oven cavity.
OUTER CASE CABINET
/
OVEN FACE PLATE
Figure C-2. Door Assembly Replacement and Adjustment
33
Page 36
R-8470 R-8570
MICROWAVE MEASUREMENT
After the adjustment of the door latch switches, moni­tor switch and door are completed individually or col­lectively, the following leakage test must be performed with a survey instrument and it must be confirmed that the result meets the requirements of the performance standard for microwave oven.
REQUIREMENT
The safety switch must prevent microwave radiation emission in excess of 5mW/cm2 at any point 5cm or more from external surface of the oven.
PREPARATION FOR
THE
TESTING:
Before beginning the actual test for leakage, proceed as follows;
I.
Make
surethat
test instrument is operating normally as specified in its instruction booklet. Important: Survey instruments that comply with the require­ment for instrumentations prescribed by the per­formance standard for microwave ovens must be used for testing.
Recommended instruments are: NARDA 8100 NARDA 8200 HOLDADYA HI 1500 SIMPSON 3800M
2. Place the turntabel tray into the oven cavity.
3. Place the load of 275
fl5ml
of water initially at 20 +5 “C in the centre of the oven tray. The water container should be a low form of 600 ml beaker with inside diameter of approx.
8.5cm
and made of an electrically non-conductive material such as glass or plastic.
The placing of this standard load in the oven is im-
portant not only to protect the oven, but also to in-
sure that ny leakage is measured accurately.
4. Close the door and turn the oven ON with the timer set for several minutes. If the water begins to boil
before the survey is completed, replace it with 275ml of the cool water.
5. Move the probe slowly (not faster that 2.5cm/sec.) along the gap.
6. The microwave radiation emission should be meas-
ured at any point of 5cm or more from the external
surface of the oven.
34
Page 37
R-8470 R-8570
1
2
3
4
5
6
PACKING AND ACCESSORIES
TRAY PACKING FOAM
s (SPADP0328WREO)
*
Not
Replaceble
Items
c
,
C
D
E
35
Page 38
m
0
0
w
D
I
I3
11
I---
--_.- -
-- _--
7
a
-. s:
0
2. GL
­CN-I
101
I 3 ,618
N-A
CN-BI
lCN-@ii
1
COOLING FANMOTOR
3
p
W-Ii-
I
(R-857
u
-. -
rAt C I
I
I c
CONTROL
PANEL
ASS’Y
TO 3PIN CONNECTOR CN-F
THERMISTOR
HEATING ELEMENT
i
ION
,ZP,N
CONNECTOR
(Al
1L ;----- _ o-.--~--
__ -
bin
.-.-
~__--
_--_--
____
~__
__
___~~~---.
r
T
0
0
W
D
m
Page 39
R-8470
R -8470
R-8570
R-8570
1
2
I
3
I
4
5
6
.I
7
I!
AC240V
50Hz
r
IN)
J-
$
fRS1,
E
r-l
\
I \-?
I
Ll
22pH
iI=
I
I
lY7479
ZD2
c30
Q30 DTA143 A
C81
I
3.3lJ/5ov
r
u
T
‘I
VI-
-
TURNTABLE
MOTOR
OVEN LAMP
r4~yB..4$IDT
FAN MOTOR A-9
dc-aC
A-7
i
A-5
fN;;CTlON
DAMPER MOTOR
*
DTA143 A x5
+
IF NOT SPECIFIED,1/4W 5%
-j + I’F
NOT SPECIFIED,
0.015~~ 25V
+
IF NOT SPECIFIED, US1060
I
t
R76 lk
-*
R71
lk
f
R66 lk
fvc
t
R65 130 F
C65
l-7
DAMPER
STOP SWITCH
SWITCH
(DOOR SWITCH)
TERMISTER
Figure S-2. Contorol Panel Circuit (Mot
1
I
2
I
3 4
I
5 6
I
7
37
Page 40
R-8470 R-8470 R-8570 R-8570
R66
lk
f
R65
G
130 F
C65
!-+T
1
KEY UNIT
1
I
1
10k
t
j-t??+
jR99 fR96 +
R97
+R96 +R95 fR94
fR9l r;;
F
'U &OS-
ln0V.l
CC.
c
B
1
7
8
I
9
10
11
12
l
A
C
VP
9
D
E
OVEN
TERMISTER
Ii
I Panel Circuit (Model R-8470)
I
7
8
I
9
I
10
11
12
38
Page 41
R-8470
R-8570
I
I
3
I
I
I
2
I
4
5
1
AC240
5Ok
TURNTABLE
MOTOR
OVEN LAMP
POWER TRANSFORMER
;&IIf&)AKt
HEATING
ELEMENT
FAN
MOT01
c$IUU;CTION
DAMPER
MOTOF
5
DTA143 A x!
+
IF NOT SPECIFIED,1/4W 5%
4 b
IF NOT SPECIFIED,
0.015~
25V
+
IF NOT SPECIFIED, US1060
I
J
I
I
I
R76 lk
R75
27k
i
iI
,
<-
R52
i.BkF
%KfT
STOP OVEN
THERMISTOR
~DO%%#TC”,
Figure S-3
I
1
I
2
1
3
4
5
39
Page 42
R-8470
R
-8570
7
8
9
10
11
I
12
'
I
1
,
NAL
VP
2
D91
10k
xt
HIGH MEDHIGH
AUTO s~,im
STOP INSTANT TIMER
START
HOLD DEFROST
(KEY UNIT
]
-I
AH
SENSOR
11 Panel
Circuit
(Model
R-8570)
/
I
7
8
I
9
10
I
11
12
40
Page 43
R-8470 R -8570
1
2
3
__--- ~-
_ _--
BFI
+
[--‘CSO’ m R90 6
,
R
q11 -lp -
u
In
z
r
liar
I)rt--9’0looe4 $
:: 01
P
~lOlOl,K E:%’
I,,
ggzr:
z
Y7-O
Rmo
:f[f:
Ll
(Lx- I
$$
-
:*71 I] r-J ggo
g pa3 &g f‘
1 II----
‘I
1
fi
$~&$:g;:j &;iti E 0,” ‘;ec!
‘g=&+-&
kn, L! 0;
0’: ’
I
e&
‘4
I gj zm 52
1 *i$yfycJ~~,3
I
a-.-Ad%
53 g ’ a g a
“Fz
i-Li._.‘.z”
4
I
3
I
"
mR*r-
IIAFI
. --
_ I
0184
n
(Control
Unit)
Figure S-4. Printed Wiring Board
(Relay Unit)
rl
B
C
D
E
F
G
H
I
1
I
I
2
3 4
5 6
I
41
Page 44
PARTS LIST
l-
1
QACCA0032WREO
Mains supply cord
I- 2
QFS- CQOOl
YBEO
Fuse (Ml OA)
I- 3
QFSHDOOl
9WREO
Fuse holder
l-
4
QSW- MO1 71 WREO
Upper latch switch (V-l
6G-1
C25)
I- 5
QSW-
MO1
73WRE0
Lower latch switch (V-l
6G-3C25)
l-
6
QSW- MO1 72WRE0
Monitor switch (V-l
6G-2C25)
I- 7
RLMPTOO38WREO
Oven lamp
l-
8
QFS-
TOO26WREO
Temp. fuse
l-
9
RMOTDA021 WREO
Turntable motor
l-10
RMOTEAOl
7WRE0 Fan motor
l-11
RMOTEA036WREO
Convection motor
1-12 .
RMOTDAOl
8WRE0
Damper motor
1-13
QSW- MO1 74WRE0
Stop switch and damper switch (V-5330DK)
1-14
RHET- A01 1 WREO Heating element
1-15
FH-
HZOO24WREO
Thermistor
l-16
RTRN-
0326WREO
Power transformer
1-17
RC-
QZOl
33WRE0
High voltage capacitor
1-18
RH-
DZOO56WREO
Rectifier
1-19
RH-
DZAOO2WREO
Short protector
l-20
RV-
MZAOO8WREO
Magnetron
I-21
RTRN-A013DREO
Transformer (for control unit)
l-22
FDTCTA034WRKO
AH sensor: R-8570 only
CABINET PARTS
2-
1
2-
2
2-
3
2-
4
2-
5
2-
6
2-
7
2-
8
2-
9 2-10 2-l 1 2-12 2-l 3 2-l 4 2-l 5 2-16 2-l 7
FDAi
-
0237WRYO
Base cabinet (A)
F
DAi
-
AO38WRYO
Base cabinet (B)
GOVNROO89WRWO
Rear cabinet
GLEGP0009YBEO
Foot
TMAPCAl
53WRR0
Schematic diagram: R-8470
TMAPCAl 54WRR0
Schematic diagram: R-8570
LBNDK0035WRPO
Capacitor holder
PCUSU0242YBPO
Cushion
LHLDK0005YBFO
Cord holder
GCABUAO56WRPO
Outer case cabinet
PCUSUOl 12YBPO
Shading cushion (A)
LANGQ0255WRWO
Capacitor mounting bracket
PSPAGQ002YBEO
Vibration proof cushion
PCAS-
0017WRFO
Plug case
LANGQ0225WRWO
Cord mounting bracket
LBSHC0032WREO
Cord bushing
LSTPP0009YBFO
Cord anchorage (lower)
LSTPP0008YBFO
Cord anchorage (upper)
CONTROL PANEL PARTS
-*
3-
1
3- 1A 3- 16 3- 1c 3- 1D 3-
1E
3-
1F
C3,C6
c4
C5,C7,C20,
C31
,C65,
c70,
c75
c5,c7,
C20,
C31,
c51-
c53,
c70,
c75
c9
Cl0
c30
CPWBF21 3SWRK0
Control unit: R-8470
CPWBF21 4SWRK0
Control unit: R-8570
QCNCMA034DREO
13-pin
connector (D)
QCNCMA040DREO
6-pin
connector (E)
QCNCMA039DREO
3-pin connector (F),(H): R-8570
QPLGJA002DREO
14-pin
connector (G)
QCNCMA047 DREO
2-pin connector (H): R-8470
RV-
KXA002DREO
Fluorescent display tube
RC-
EZA059DREO
Capacitor 10
FF
RC-
EZAO61
DREO Capacitor
4.7
FF
RC-
KZAOO4DREO
Capacitor
0.015
/-IF
25V 5ov 25V: R-8470
RC-
KZA004DREO
Capacitor 0.015
FF
25V: R-8570
RC-
EZA057DREO
RC-
EZA058DREO
RC-
EZAOGODREO
Capacitor Capacitor Capacitor
100
FF
22
PF
47
FF
42
16V 25V 16V
ELECTRICAL
PARTS
1 1 1 1 1 1 2 1 1 1 1 1 2 1 1 1 1 1 1 1 1 1
1
1 1 4 1 1 1 1
1 1 1 1 1 1
1
1 1 1
1 1 1
:
1 1 1
2 1 7
9
1 1 1
AR
AE
AF AG AG AG AH AG
AX
AW AW
AR AH
AY
AQ
BR
AZ
AQ AQ
BL
AW
BB
AR
AU
AV
AB
AC
AB
AB
A0
AB
BA
AA
AC
AA
AD
AC
AB
AC
AC
BV
BU
AD
AC
AB
AE
AB
BC
AB
AB
AA
AA
A0
AB
AB
Page 45
* *
* * *
* A
* *
1 1 $I + 1
4 * *
9 * *
* *
*
* * *
*
* * *
R-8470 R-8570
Note
: The voltage supplied to the parts marked
U*N
is greater than
25OV.
* :
Refer to “REPLACEMENT PARTS LIST” described at after page.
REF.
NO.
PART NO.
DESCRIPTION
Q’TY 1 CODE
:
c50 C80 C81
CFl
D7,D20,
DBO-
D83,
D91, D94- D99,
D105
D7,DlO,
D20,D51,
D52,
D81-
D83,
D91
,D92, D94- D99, D105
D8,D9 DB,D9,DlO
ICl IC2 Ql 030,Q41,
Ql 00
Q50,081,
Q83-Q86 Q80 Q81,
Q83-086 082 Rl
R2 R3 R4 R22, R82,
R201
,R203
R22,R54,
R82, R203
R23,R31,
R202 R30 R50 R51
R55,R81,
R91,
R92,
R94- R103
R65
R66,
R71,
R76,
R80
R66,R71,
R76,
R80,
R201 R67 R70, R75,
Rlll
R81,
R91,
R94-R103
R83 R84
R90
RllO
Rll2
R113 R200 R204
ZDl
ZD2 ZD30
RC-
KZl
04QDRE0
RC-
EZAO63DREO
RC-
EZA062DREO
RCRS-
A003DREO
RH-
DZA002DREO
RH-
DZA002DREO
Diode (US1 060): R-8570
17 AA
RH- DZAOl 1 DREO RH- DZAOl 1 DREO
RH- i
X2429DREO
RH- i ZOO21 WREO RH-
TZ0029DREO
RH- TZA042 DREO
Diode (11 ES1 ): R-8470
FEde (11ESl):
R-8570
IC (lR94558): R-8570 only
Transistor
(2s B953Q,
R)
Transistor
(DTAl43E.S)
2
AB
3 AB 1
AV
1
AE
1
AG
3
AB
RH-
TZA022DREO
Transistor (
DTAl43A):
R-8570
6 AB
RH-TZA025DREO
RH-
TZA022DREO
Transistor
(2SC2021 MQ,R,S)
Transistor
(DTAl43A):
R-8470
1 5
1 1 1 1 1 4
4
3
1 1 1
14
1 4
5
1 3
12
1 1 1 1 1 1 1 1
1 1 1
AB AB
RH- TZA021 DREO
RR- DZ331 NDREO
RR-
DZl
51 PDREO
RR-
DZl
21 PDREO
RR- DZ271 PDREO
RR-
DZ473DDREO
AC AA AA AA AA AA
RR-
DZ473DDREO
Transistor
(2SB91
OMR)
Resistor 330
n
Resistor
150
n
Resistor
120n
Resistor 270
n
Resistor 47k
n
Resistor 47k
n
Resistor
15kn
Resistor 470
c2
Resistor block
(RNAFST)
Resistor
330
n
Resistor
IOkn
1/4w 1/2w lj2W 1/2w 1/4W:
R-8470
1/4W:
R-8570 AA
RR-
DZl
53DDRECI
1
l4W
AA
RR- DZ471 NDREO
RR-
DZA005DREO
RR- DZ331 PDREO
RR-
DZl
03DDRE0
1/4w
1/2w 1/4W:
R-8570
AA AA AA AA
RR-
NZl
31 NDREO
RR-
DZI
02DDRE0
RR-
DZl
02DDRE0
RR-
NZ5,02NDREO
RR-
DZ273NDREO
RR-
DZI
03DDRE0
RR-
DZ472+
r
kE0
RR- DZ222 DREO RR-
DZA029DREO
RR-
DZA027DREO
RR-
DZA028DREO
RR-
DZ563NDREO
RR-
DZ204DDREO
RR-
02201
NDREO
RH-
EZA050DREO
RH- EZA051 DREO RH-
EZA052DREO
T
Capacitor
0.1
PF
Capacitor
0.47
/JF
Capacitor
3.3
PF
Ceramic filter
(4.0MHz)
Diode (US1 060): R-8470
25V: R-8570 25V
5ov
Resistor
130
R(F)
Resistor
lkfi
Resistor
lkn
Resistor
5k
n(F)
Resistor 27k
R
Resistor
10kn
Resistor
4.7k n
Resistor
2.2k n
Resistor block (1
OOk nx4)
Resistor block (27k
nx6)
Resistor block (56k
nxl4)
Resistor 56k
n
Resistor
200k
n
Resistor
200
n
Zener diode
(RD16EB3)
Zener diode (RD5.1 EB3) Zener diode
(RD3.6EL2)
43
1/4w 1/4W:
R-8470
ll4W:
R-8570
1/4w ll4W
1/4W:
R-8470
1/4w 1/4w
ll4W
1/4w
1 l4W: R-8570 only
1
AB
1
AB
1
AB
1
AF
14 AA
AA AA
AA
AA AA
AA
AA
AA AB AC AD AA AA AA
AB
A0 A0
Page 46
R
-8470
R
-8570
Note : The voltage supplied to the parts marked ‘I*” is greater than
25OV.
*
:
Refer to “REPLACEMENT PARTS LIST” described at after page.
REF. NO.1
PART NO.
DESCRIPTION
j
Q’TY 1 CODE
3-2
.=c
3-
2A
3- 20 3-
2c
3-
2D
3-
2E
Cl c2
C8
Cl 80
Dl -D5
D84,
D181-D186
Fl
:40 R20
R21
,R42
R40 R41
RYl -
RY6
SP40
VRSl
3-
3
3-
4
3-
5
3-
6
3-
7
4-
1
4-
2
4-
3
4-
4
4-
5
4-
6
4-
7
4-
8
4-
9 4-l 0 4-l 1 4-l 2 4-l 3 4-14 4-l 5 4-l 6 4-l 7 4-l 8 4-l 9
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
-FPWBFAO62WREO QPLGJ2396YAZZ QCNCM239OYAZZ
QCNCM231
8YAZZ
QPLGJ2397YAZZ
QFSHA2002YAZZ VCQYCUl HM104K VCEAAHl
VW1
08h
VCTYPUI EFl
042
VCEAAU~ HWI
06n
VHDl1El/l/l-1
VHDUS1060,‘/-1
n
A
QFS-
A2042YAZZ
RCi LF2003YAZZ VS2SA937Ql
I -
1
VRD-
ST2EFl
83J
VRD-
ST2EF103J
VRD-
ST2EFl
54J
VRD-
ST2EF471
J
RRLY- 21
18YAZZ
RALM- 2021YAZZ RH-
VX201 SYAZZ
DUNTKAO91
WREO
DUNTKAO92WREO GMADi
A031 WRRO
HPNLCAl
59WRJ0
LANGTAO46WRWO LCHSMAOI 4WRWO
FOVN-
AO29WRYO PCUSU0373WRPO
NCPL-
AOO7WRFO
NTNT-
AOO5WRHO LFi
X-
AOO7WRFO PCOVPA050WREO PGLSPOOl
5YBE0
LANGQAO42WRWO
PDUC-
03OOWRFO
PDUC-
AO75WRFO LANGQA026WRPO FFANJ0030WRKO LANGKOl
40WRW0
LANGF0224WRPO LANGK0309WRFO MLEVFOl
24WRE0 LANGK031 1 WRFO
MLEVP0080WRFO
PDUC-
0466WRWO
PDUC-
0508WRWO
PDUC-
AO93WRWO
PDUC-
AO73WRWO
FDUC- 01 91 WRWO
PCUSU0373WRPO
PGi DHAOO7WRWO PREFHA005WRPO PREFHA004WRPO PREFHAOO7WRWO PREFHAOOGWRPO
PREFH0031 WRPO
GCOVHO238WRWO PCUSU0279WRPO
PFPF-
AOO9WREO
PFPF-
0036WREO
PFPF-
AOO8WREO
PDUC-
AO94WRWO
PDUC-
0299WRWO
FSKR- AOO2WRWO
PGi DJAOO2WRWO
FFANMA002WRYO
NBLTKAOO5WREO
NPLYBOO3OWRFO
Relay unit
12-pin
connector (A)
&pin
wire connector
(0)
13-pin
wire connector
(C)
8-pin connector (I)
Fuse holder Capacitor
0.1
PF
Capacitor
1000
FF
Capacitor
0.1
PF
Capacitor
10
FF
Diode (11 El ) Diode (US1 060)
5ov 35v 25V 5ov
Fuse Filter coil (22
PH)
Transistor
(2SA937Q)
Resistor
18kn
Resistor
10kn
Resistor 150k
n
Resistor
470
n
Relay
(D.C.14V)
Buzzer
Varistor
Key unit: R-8470 Key unit: R-8570 Display filter Control panel frame Key unit angle Control panel back plate
ll4W lI4W 1/4w 1/4w
OVEN PARTS
Oven cavity Shading cushion (B)
Turntable coupling Turntable tray
Oven lamp glass flange
Waveguide cover
Oven lamp screen glass Oven lamp mounting plate Magnetron cooling duct (A) Magnetron cooling duct (B)
Turntable motor mounting plate
Fan blade assembly Hinge mounting plate Chassis support Upper latch hook Monitor switch lever Lower latch hook
Stop switch lever Steam duct (left): R-8470
-_
Steam duct (left): R-8570 Steam duct (right)
. Steam duct (upper) Steam duct (top) Steam duct cushion (A) Air guide duct Thermal protection plate (left) Thermal protection plate (right) Thermal protection plate (oven cavity top) Thermal protection plate (upper) Thermal protection cover Sensor cover: R-8570 only Steam duct cushion (B) Thermal protection sheet (right) Thermal protection sheet (left)
Thermal protection sheet (upper)
Convection air duct (upper) Convection air duct (left) Convection air guide (left) Convection air guide (upper) Convection fan Convection fan belt Pulley A (for convection fan)
44
1
BH
1
AD
1
AM
1
AM
1
AC
1
AA
1
AB
1
AH
1
AA
1
A0
5
AB
7
AA
1
AC
1
AC
1
A0
1
AA
2
AA
1
AA
1
AA
6
AN
1
AF
1
AF
1
AY
1
AY
1
AH
1
AU
1
AK
1
AK
1 1 1
1
1 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
:
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
1
BR
AA
AF
AU
AK
AG
AF
AF AG AH
AF
AE
AC
AE
AF
AF
AF AC
AE
AE AD AG AH AA
AE AH
AQ
AF AN AG
AE AA
AM
AH
AM
AQ
AK AK
A0
AG
AF AC
Page 47
R-8470 R-8570
Note :
The voltage supplied to the parts marked
I’*,,
is greater than
25OV.
*
: Refer to “REPLACEMENT PARTS LIST” described at after page.
REF.
NO.
PART NO.
DESCRIPTION
)
Q’TY 1 CODE
4-42
NPLYB0031 WRFO
Pulley 0 (for convection motor)
1
4-43
LANGQ026OWREO
Convection motor mounting plate
1
4-44
FBRGMAOOl
WREO
Fan shaft
1
4-45
LFi
X-
AOOBWRWO
Shaft mounting plate (A)
1
4-46
LANGTAO5OWRWO
Shaft mounting plate
(0)
1
4-47
PGi SHOO38WREO
Heating element holder
2
4-48
PDUC- A071 WRWO
Damper duct
1
4-49
PFTA-
AOO7WRWO
Damper
1
4-50
NSFTT0071 WREO
Damper shaft
1
4-51
PCUSUO269WRPO
Damper cushion
1
4-52
MCAMPAOl
1 WREO
Damper cam
1
4-53
PCUSU0471 WRPO
Steam duct cushion (C)
1
4-54
PGi
SH0041 WREO
Heating element insulator
1
4-55
FROLPAOOBWRKO
Turntable roller assembly
1
5
5-
1
5-
2
5-
3
5-
4
5-
5
5-
6
5-
7
5-
8
5-
9 5-10 5-l 1 5-l 2 5-13 5-14 5-15 5-16 5-17 5-18
5-l 9 5-20 5-21 5-22 5-23
CDORFAO92WRKO
Door assembly, complete: R-8470
1
CDORFAO94WRKO
Door assembly, complete: R-8570
1
FANGTOO92WRYO
Latch plate
1
FLEVFOl
06WRYO
Joint lever
1
LSTPPAOl
8WRFO
Upper latch head
1
LSTPPAOl
9WRFO
Lower latch head
1
MSPRT0059WREO
Latch spring
1
HDECQAO4OWREO
Door sash upper
1
DDORFA053WRYO
Door panel ass’y
1
HDECQAO29WRFO
Door sash (right)
1
HDECQAO3OWRFO
Latch cover
1
LX-
BZOl43WREO
Screw (torx); latch cover mtg
3
HDECQA041 WREO
Door sash (lower)
1
HDECAAO33WREO
Door decoration plate
1
PSLDMAO29WRFO
Ferrite
1
LANGTAO47WRWO
Sash mounting plate (upper)
1
LANGTAO48WRWO
Sash mounting plate (lower)
1
FHNG-
0078WREO
Door hinge ass’y
1
HDECQA028WRFO
Door sash (left)
1
PGLSPAO45WREO
Door glass: R-8470
1
PGLSPAO46WREO
Door glass: R-8570
1
PCUSG021 3WRP0
Door sushion (short)
2
PCUSG021 2WRP0 Door cushion (long)
2
PSLDMAO38WREO
Door ferrite (upper)
2
LX-
CZAOl
7WRE0
Screw; sash mounting plate mtg
6
LX-
CZOO26WREO
Screw; door hinge ass’y mtg
5
6-
1
6-
2
6-
3
6-
4
6-
5
6-
6
6-
7
6-
8
6-
9
6-l 0 6-l 1
6-12 6-13
FAMi - AOO9WREO FAMi - AOO8WREO
QW-
HZOO59WREO
QW-
HZOO68WREO
FW-
VZAl
86WRE0
FW-
VZAl
85WRE0
LHLDWQ002YBEO LHLDWQ005YBEO LBNDCQ004CBEO
TSPCNA31 2WRR0
TSPCNA31
3WRR0
TCAUHOl 14WRRO TCADCO222WRRO
Ti
NSEAl
69WRR0
Ti
NSEAl
70WRR0
SCREWS, NUTS, WASHERS,
PINS AND RING
7-
1 LX-
BZ0055YBEO
7-
2
LX-
BZOl
41 WREO
7-
3 LX-
BZOl
86WRE0
7-
4 LX-
CZOOl
7WRE0
7-
5 LX-
CZOO47WREO
7-
6 LX-
CZOO52WREO
DOOR PARTS
MISCELLANEOUS
High voltage wire A (Trans.-Capa.) High voltage wire B
(Msg.-Capa.)
Main wire harness Thermistor harness Wire holder Wire holder
(Puree
lock “EXL”)
Wire holder (WH-1
,“M”)
Name plate: R-8470 Name plate: R-8570 Caution label Cook book Operation manual: R-8470 Ooeration manual: R-8570
Screw ;waveguide cover mtg Screw ;monitor switch lever mtg Screw ; cord mounting bracket, capacitor mounting bracket,
magnetron cooling duct (B), base cabinet (A) and rectifier
mtg
Screw ; convection air guide (upper) mtg Screw ; rear cabinet, base cabinet (A), (B) and control panel
assembly mtg
Screw
;
upper and lower latch hook mtg
1 1 1 1 1 1
:
2 1 1 1 1 1 1
AC
AK
AQ
AC AC AL AL
AD
AA AA AC AA
BS
BT
AE AD AC AC AC
AM
BF
AH
AK AA
AM
I%
AF
AF
AS AH
AZ
AZ AA
A0
AE AA AA
AS
AS AD AD
AX
AL AA AA AA AC
A0
AC
BA
AK AN
AA AA AA
AA AA
AA
45
Page 48
R-8470 R-8570
Note :
The voltage supplied to the parts marked
“*”
is greater than
250V.
*
: Refer to “REPLACEMENT PARTS LIST” described at after page.
REF. NO.1
PART NO.
DESCRIPTION
1
Q’TY 1 CODE
7-
7
7-
8
7-
9 7-10 7-11 7-12 7-13 7-14 7-15 7-16 7-17
7-18 7-19 7-20 7-21 7-22
7-23 7-24 7-25 7-26 7-27 7-28
7-29 7-30
7-31
7-32 7-33 7-34 7-35
7-36
7-37 7-38 7-39 7-40 7-41
LX-
EZOO46WREO
Screw ; outer case cabinet mtg
2 AB
XBPSD30Pl
2KOO
Screw ; fuse holder mtg
1
AA
XBPSD30Pl
6KOO
Screw ; damper switch mtg
1
AA
XBPSD40P25000
Screw ;
fan motor and convection motor mtg
4 AA
XBPSD50Pl
2KOO
Screw ;
magnetron mtg
3
AA
XBPSD50Pl
2KS0 Screw ; magnetron mtg
AA
XBPSDGOPl
4KS0 Screw ; power transformer mtg
:
AA
XBPUW40P10000
Screw ;
heating element mtg
2 AA
XBSSD40Pl
2000
Screw ; door assembly mtg
4 AA
XBTUW4OPO6000
Screw ;
waveguide cover mtg 3
AA
XBTUW4OPO8000
Screw
;
damper duct, convection air duct (upper), (left), oven 17
AA
lamp mounting plate and shaft mounting plate mtg
XCBWvv30P08000
Screw ; thermistor mtg 2
AA
XCPSD30P06000
Screw ; AH sensor and sensor cover mtg: R-8570 6 AA
XCPSD30P08000
Screw ;
oven lamp mtg
2
AA
XCPSD30Pl
0000 Screw ; damper motor mtg 2
AA
XCPSD40P08000
Screw ;
damper duct, steam duct (right), (left), (upper), thermal
21
AA protection plate (right), (left), thermal protection cover, oven lamp mounting plate, sensor cover and air guide duct
mtg
X C P S D4 0 P 2 7 0 0 0
Screw ; cord anchorage (upper) mtg 2 AA
XCPWW3OPl
oxuo
Screw ;
heating element holder and heating element insulator mtg 4 AA
XCTSD40P08000
Screw ; convection motor mounting plate and damper duct mtg
4
AA
XCTSD40Pl
0000
Screw ;
cord anchorage (lower) mtg
1
AA
XFTSD40Pl
0000
Screw ;
plug case mtg
1
AA
XHPSD30Pl
2XS0
Screw ; transformer (for control unit), relay unit and control unit 8 AA
mtg
XOTSC40Pl
2000
Screw ;
outer case cabinet mtg
8
AA
LX-
NZ0029YBEO
Nut ; convection air duct upper, oven lamp mounting plate
9
AA and convection motor mtg
LX-
NZOO7OWREO
Nut
;
earthing
AA
XNESD40-
32000
Nut ; fan motor mtg
:
AA
XNEUW40-
32000 Nut ; convection fan mtg
1
AA
XWHEZl 2-
05300
Washer ; turntable coupling mtg
1
AA
XWHSD50-
08000
Washer ; monitor switch lever mtg
1
AA
XWHUW40-
08000 Washer ; convection fan mtg
1
AA
xwsuw40-
10000
Washer ; convection fan mtg
1
AA
XVvWSD60-
08000
Washer ; power transformer mtg
XPNSC80-
- - 000
Pin ; convection fan and pulley (A) mtg
:
AA
AA
XPNSDGO-
- - 000
Pin ;
pulley (B) mtg
1
AA
XRSSPl 2-
04000 Ring ; turntable coupling mtg
1
AA
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
46
Page 49
R
-8470
R-8570
REPLACEMENT
PARTS LIST
This replacement
parts
list shows tnterchangeabillty of
marked ( *) parts on
the control panel parts to the alterations
of
product locatlons.
This
lrst
has
been prepared to
show
LISTED PART NO
along with the
USED PART NO
side
by side.
REF. NO.
C3 et.c
c4 C5 etc
c9
Cl0
C3O c50 C8O C81
D7 etc
D8
etc
IC2 01
Cl50 etc 080
082
LISTED PART NO.
USED PART NO.
_ ._-.~--
----
RC-
EZA059DREO
RC-
EZTIOGAFI
E
RC-
EZAO61
DREO
RC-
EZT475AFl
E
RC-
KZA004DREO
+CKYATl
EXI
53N
RC-
EZA057DREO
RC-
EZTl 07AFl
C
RC-
EZA058DREO
RC- EZT226AFl
E
RC-
EZAOGODREO
RC-
EZT476AFl
C
RC-
KZI
04QDRE0
L!CTYPGl
EFlO4Z
RC-
EZA063DREO
RC-
EZT474AFl
H
RC-
EZAO62DREO
ARC- EZT335AFl
H
RH-
DZA002DREO
L’HDUSl 06C; -
1
RH-
DZAOl
1 DREO
;‘HDl
1 El
I
1
RH- I ZOO21 WREO RH- I X21
54bAZZ
RH-TZ0029DREO
VS2SB953-
Q/ 1
RH-TZA022DREO
L’SDTA
143-A-l
RH-TZA025DREO
‘VS2SC2021
/
f 1 A
RH-TZA021 DREO
VS2SB851
R/ / -
1
REF. NO.
RI
R2 RS R4
R22 etc
R23 eic
R30 R55
e:c R66 e:c R70
etc
R83
R84
R113
R200 R204
LISTED PART NO.
USED PART NO.
R;1- DZ331
NDREO
L
RD-
ST2EF331
J
RR
DZl
51 PDREO ‘, SD-
ST2HAl
51 J
RR-
DZl
21 PDREO ‘x RD-
S72HAl
21 J
RR-
DZ277 PDREO
-.‘RD- ST2HA271
J
RR-
DZ473DDREO
,‘RD- ST2EF473J
RR-
DZl
53DDRE0
,‘RD- ST2EFl
53J
RR- DZ471
hDRE0
e
RD- ST
2EF471
J
UK- DZ103CDREQ
.RD-S’2EF103J
‘(H- DZ102NDREO
QRD- S’2EF102J
HR- DZ273NDREO
.iRD- ST2EF273J
PR- DZ472NDREO
s,‘RD-ST2EF472J
RR-
DZ222DDREO
\‘RD- ST2EF222J
RR- DZ563NDREO
L’RD- ST2EF563J
FR- DZ204DDREO
11 R
D - S
-2EF204J
RR-
DZ201NDREO
JRD-STZEFZOlJ
SERVICE INFORMATION FOR CONTROL UNIT
--
Some sets of 1st
lot of model R-8470
have
jamper wires J54
and
.J55 inserted
So, please
adjust them to improve
performances of
LSI,
complying with this Service Manuai
The
following are steps to take:
(1)
Remove
jamper wires J54
and
J55 from
PWB of
control unit to
open Its pin nos 51 and 52 of LSI.
(2) Add
C65 to
PWB of control unit.
47
Page 50
R-8470 R-8570
1
2
3
j
4
5
6
I
CABINET
PARTS
I 1
I
1
I
2 / I
3
I
4
I
I
5
6
48
Page 51
R-8470 R-8570
1
2 3 4
5
6
I
i
E
/
I
I
1
2
49
Page 52
R-8470 R-8570
1
2
I
/
3
4
5
6
1
I
1
I
2
3
4
5
I
6
50
Page 53
R-8470 R-8570
1
2
I
3
I
4
5
6
DOOR
ASSEMBLY
MISCELLANEOUS
6-3
Trans.
m
I
I
I
/
I
I
/
I
i
I
t
Page 54
R-8470 R-8570
General:
Connect:
FIXING PROCEDURE OF CORD ANCHORAGE
As for the above subject, sometime it may cause to have wrong fixing about two pieces of cord anchorage unit. But this cord anchorage is an important part for the safety, therefore it must be fixed correctly and firmly.
1.
The cord anchorage which is used to secure the mains supply cord can be fixed in two different ways.
2.
If you fix them s shown in Figure 2, the mains supply cord will not be secured firmly.
3.
Therefore, make sure to fix them as shown in figure 1.
LSTFFOOO8Y
BFO
SUPPLY
CDRD
ANCHORAGE
WPPER) LBTPPWlO8YBFO
Figure 1. Correct Fixing
Figure
2. Wrong Fixing
.3
mm
‘86 0 SHARP CORP. (9N0.75E) Printed in Japan
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