manuals.online logo
Brands
  1. Home
  2. •
  3. Brands
  4. •
  5. Sharp
  6. •
  7. Microwave Oven
  8. •
  9. Sharp R-9380 User manual

Sharp R-9380 User manual

SHARP SERVICE MANUAL
S0705R9380J//
MICROWAVE OVEN
MODEL R-9380
In the interests of user-safety the set should be restored to its original
condition and only parts identical to those specified should be used.
(RDlGlOlU)
TABLE OF CONTENTS Page
FOREWORD ....................................................................................................................................................... 1
CAUTION, MICROWAVE RADIATION .......................................................................................................... 1
PRODUCT DESCRIPTION ............................................................................................................................... 2
OPERATION ....................................................................................................................................................... 4
SERVICING ... . ................................................................................................................................................. 7
TOUCH CONTROL PANEL ASSEMBLY . ..,..........,.............................................,.............*....................,.... 15
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ...................................................... 22
MICROWAVE MEASUREMENT PROCEDURE .. ....................................................................................... 26
PICTORIAL DIAGRAM .................................................................................................................................. 27
CONTROL PANEL CIRCUIT ......................................................................................................................... 28
PRINTED WIRING BOARD .......................................................................................................................... 29
PARTS LIST ..................................................................................................................:................................. 30
PACKING AND ACCESSORIES ................................................................................................................... 38
SHARPCORPORATION
SERVICE MANUAL
SHARP
i; PRODUCT DESCRIPTIOF
MICROWAVE OVEN
R-9380
FOREWORD
This Manual has been prepared to provide Sharp Corp. Service
Personnel with complete Operation and Service Information for
the SHARP MICROWAVE oven, R-9380.
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 micro-
wave radiation hazard. (RD361 OZU)
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 microwave energy absorbing load attached. Never look into
an open waveguide or antenna while the device is energized.
Note( Parts List) : The parts marked rr*rr are used in voltage
more than 250V. (RD36202U)
SHARPCORPORATION
OSAKA, JAPAN
f :.-.u_i
; OPERATION ‘-..
g SERVICING i&gji.
#g&&i;:
TOUCH CONTROL qq;y$;.
“y&qrs.
“-OS...
PANEL ASSEMBLY ,*.fie,
,+~‘;l~
E,
$I COMPONENT
2; REPLACEMENT AND
g! ADJUSTMENT
MICROWAVE
MEASUREMENT
WIRING af
(RD
37201 U)
R-9380
PRODUCT DESCRIPTION
EXPLANATION OF MICROWAVE COOKING
The Sharp Microwave Oven uses microwave energy to moisture content, like most foods, will absorb micro-
produce heat in the food to be cooked. Unlike con- wave energy. As the microwave energy at a frequency
ventional ovens microwave energy will cook foods of 2450 Megahertz enters the food, the molecules align
without applying external heat. themselves with the energy. Because the microwaves
are changing polarity every half cycle, the food mole-
Microwaves, which are short electromagnetic waves cules are changing direction every half cycle or oscil-
of RF (radio frequency) energy, pass through materials lating back and forth 4,900,000,000 times per second.
such as glass, paper, china and most plastics. Materi- This high speed oscillation causes friction between the
als such as metal and aluminum foil tend to reflect molecules, thereby converting the microwave energy
microwaves and may be used only as recommended in to heat. (AD41 101 U)
the cooking instructions. Materials with a high
I. SPECIFICATION
F ITEM DESCRIPTION
Power Requirements 240 Volts
50 Hertz
Power Consumption
Power Output
Case Dimensions
Single phase, 3 wire earthed
14oow
700 watts nominal of RF microwave energy (2 liter water load)
Operating frequency of 2450MHz
Width 616 mm
Height 367 mm
Depth 477 mm
Cooking Cavity Dimensions Width 406 mm
Height 248 mm
Depth 422 mm
Control Complement
P-L \A,-‘- LL
381 vvergnr
/ Touch Control System
Clock( I:00 - 12:59 )
Timer (0 - 99 min. 99 sec. )
Microwave Power for Variable Cooking
Repetition Rate;
HIGH ............................. Full power throughout the cooking time
MED HIGH ............................................ approx. 70% of Full Power
MED ....................................................... approx. 50% of Full Power
MED LOW (DEFROST) ...................... approx. 30% of Full Power
LOW ....................................................... approx. 10% of Full Power
HOLD ................................ No power throughout the cooking time
INSTANT COOK/START
AUTO START COOKING
EASY DEFROST COOKING
/ EASY REHEAT COOKING
1 MORE( )/LESS( ) pad
L--- o-n-
/ npprox. LJ KQ
(RD44101
NOTE:’ Numbers and leters shown after sentences such as “RD44101 U” are for factory use only.
2
OVEN DIAGRAM
1. Ventilation openings
2. Oven lamp
3. Oven door with see through window
4. Removable turntable
5. Roller Stay
6. Door latches
7. Door button
open
8. Auto-Touch Control Panel
9. Digital readout
10. Waveguide cover
11. Access cover for oven lamp replacement
Auto-TouchTM Control Panel
r NUMBER PADS
I \I ,
1 ’ 11 EASY REHEAT j
3 l.Dmner plate .._. I-2~lales
2.Chicken......---.,.l-6pcs
3.CassetolelSouP-l-4cups
4,ptZZa ,-Bpcs
5.Eleverage ......... I-4cups
1 7 11n’-LOd I--
r
INSTANT COOK
START
I
12. Door hinges
EASY REHEAT PAD
EASY DEFROST PAD
VARIABLE COOKING CONTROL PADS
MORE I A I. LESS ( ‘I ) PADS
AUTO START/CLOCK PAD ._
TIMER/HOLD PAD
INSTANT COOK/START PAD
STOP/CLEAR PAD
3
-~
R-9380
OPERATION
DESCRIPTION OF OPERATING SEQUENCE
The following is a description of component functions
during oven operation. (RD7!101Ul
OFF CONDITION
Closing the door activates both door latch switches:
upper latch switch and lower latch switch. (In this
condition, the monitor switch contacts are opened.)
The stop switch is activated by the latch head.
When oven is plugged in, 240 volts A.C. is supplied to
the control unit.
But no components in the oven will operate.(Figure
o-1 .)
Note: When the door is opened by pushing the door
open button, the contacts of the relay RY-1 are
closed, then the oven lamp lights.
1. The display will show flashing “88:88”.
To set any program or set the clock, you must
first touch the STOP/CLEAR pad.
The display will clear, and 1:00 will appear and
count up every minute.
COOKING CONDITION
‘HIGH COOKING CONDITION
Program desired cooking time and Variable Cooking
Control by touching the NUMBER pads and the HIGH
pad of the Variable Cooking Control. When the START
pad is touched, the following operations occur:
1. The contacts of relays are closed and components
connected to the relays are turned on as follows.
(For details, refer to Figure O-2)
2.
3.
4.
5.
RELAY
-Fw1
RY-2
CONNECTED COMPONENTS .---.-
oven lampjturntable motor/fan motor
power transformer
240 volts A.C. is supplied to the primary winding
of the power transformer and is converted to about
3.5 volts A.C. output on the filament winding, and
approximately 1900 volts A.C. on the high voltage
winding.
The filament winding voltage heats the magnetron
filament and the H.V. winding voltage is sent to a
voltage doubler circuit.
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.
Upon completion of the cooking time, the power
transformer, oven lamp, etc. are turned off, and the
generation of microwave energy is stopped. The
oven will revert to the OFF condition.
6. When the door is opened during a cook cycle,
monitor switch, upper latch switch and lower latch
switch are activated with the following results. The
circuits to the turntable motor, the cooling fan mo-
tor, and the high voltage components are deener-
gized, 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 mechan-
ically associated with .the door so that it will func-
tion in the following sequence.
(1) When the door opens from a closed position,
the stop switch, upper and lower latch switches
first operate to open 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 stop switch, upper
and lower latch switches close.
In case the upper latch switch fails with its contacts
closed when the door is opened, the monitor switch
will form a short circuit through the fuse M6.3A, and
the upper latch switch, causing the fuse M6.3A to
blow.
MED HIGH, MED, MED LOW (DEFROST), LOW,
HOLD COOKING
When Variable Cooking Power is programed, the 240
volts A.C. is supplied to the power transformer
intermittently through the contacts of relay( KY-2)
which is operated by the control unit within a 32 sec-
ond time base. Microwave power operation is as fol-
lows:
VARI-MODE ON TIME
HIGH 32 sec.
.__--
OFF TIME
0 sec.
(100% power) __---_-- ~_.-.-
ME0 HIGH 24 sec. 8 sec.
(approx. 70% power)
MED 18 sec. 14 sec.
(approx. 50% power)
_. ~~.~ -_. ~~.~~-.--- ..--.- _-----. ~- .-~.. -. - -- ~~
MED LOW (DEFROST) 12 sec. 20 set
(approx. 30% power)
..Low 6 sec. 26 sec.
(approx. 10% power)
HOLD 0 sec. 32 set
(0% power)
- ___.
Note: The ON/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. (RD71401U)
z YI
Y$$&
Om'Fz
bS"CG pn
z"Z amoCuJ
-aaaag
OE$$nga3
kOoaaot;;o
0 nnvn>v: t-
FZ..
<V-w ti i
I ..
"P
;s
5
R-9380
DESCRIPTION AND FUNCTION OF COMPONENTS
MAGNETRON TEMP. FUSE
The temp. fuse located on the cavity top plate near the
magnetron to prevent damage to the magnetron if an over
heated condition develops in the tube due to cooling fan
failure, obstructed air ducts, dirty or blocked air intake, ect.
Under normal operation, the temp. fuse remains closed.
However, when abormally high temperatures are reached
within the magnetron the fuse will open at 115°C causing
the oven to shut down. This is a fuse and it dose not reset.
OVEN THERMAL CUT-OUT
The oven thermal cut-out is located on the rear side of.steam
duct. If is designed to prevent damege to the oven cavity
is foods in the oven catch fire due to overheating produced
by improper setting of cooking time etc. Under normal
operation, this thermal cut-out remain closed. However,
when abnormally high temperatures are reached within the
steam duct thermal cut-out will open causing the oven to
shut down.
DOOR OPEN MECHANISM
The door can be opened by pushing the open button on the
control panel, refer to Figure D-l. When the open button is
pushed, the open plate on the open device pushes in the door
lever on the door, operating the latch head linkage. The lower
and upper latch heads are moved upward, and released from
the lower and upper latch hooks. Now, the door can be opened.
DOOR
/ASSEMBLY
UPPER
LATCH
HEAD
DOOR
OPEN
BUTTON
Figure D-l. Door Open Mechanism
LOWER AND UPPER LATCH SWITCHES
The lower latch switch is mounted in the lower latch hook and
the upper latch switch is mounted in the upper latch hook. They
are activated by the latch heads on the door. When the door
is opened, the switches interrupt the circuit to all components
except the oven lamp.
A cook cycle cannot take place until the door is firmly closed
therebv activating both interlock switches.
MONITOR SWITCH
The monitor switch, mounted on the upper latch hook, is actl-
vated (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 failes to open when the door
is opened.
Functions:
1. When the door is opened, the monitor switch contacts close
(to ON condition) due to their being normally closed. At this
time the upper latch switch is in the OFF condition (con-
tacts open) due to their being normally open contact
switches.
2. As the door goes to a closed position, the monitor switch
contacts are first opened and then the upper latch switch
contacts close. (On opening the door, each of these
switches operate inversely.)
3. If the door is opened and the upper latch switch contacts
fail to open, the fuse blows simultaneously with the clos-
ing of the monitor switch contacts.
CAUTION: BEFORE REPLACING A BLOWN FUSE, TEST
THE UPPER LATCH SWITCH SWITCH AND
MONITOR SWITCH FOR PROPER OPERATION.
(REFER TO CHAPTER “TEST PROCEDURE”)
UPPER
LATCH
HOOK
MONITOR
SWITCH
UPPER
LATCH
SWITCH
LOWER
LATCH
HOOK
STOP
SWITCH
LOWER
LATCH
SWITCH
,
Figure D-2. Latch Switches and Monitor Switch
s
R-9380
SERVICING
TROUBLESHOOTING GUIDE
When troubleshooting the microwave oven, it is helpful to
follow the Sequence of Operation in performing the checks.
Many of the possible causes of trouble will require that a
specific test be performed. These tests are given a procedure
letter which will be found in the “Test Procedures section.”
IMPORTANT: If the oven becomes inoperative because of a
blown fuse in the monitor-upper latch switch
circuit, check the monitor switch and upper
latch switch before replacing the fuse.
PROBLEM POSSIBLE CAUSE TEST PROCEDURE OR
CORRECTION
OFF CONDITION
Home fuse blows when power cord
is plugged into wall receptacle. Shorted wire in power cord or wire harness. Replace cord or check wiring.
Fuse M6.3A blows when power
cord is plugged into wall
receptacle.
Shorted wire in power cord or wire harness. Replace power cord or check
and repair wire harness.
Defective monitor switch. Procedure G.
” 88:88 ” does not appear in display
when power cord is first plugged
into wall outlet.
No power at outlet. Check home fuse.
No power from service entrance. Check wall outlet.
Open wire in power cord or wire harness.
Blown fuse M6.3A.
Defective temp. fuse.
Replace same or repair wiring.
Procedure H.
Procedure F.
Defective thermal cut-out.
Open wire In power cord, wiring harness,
or wrring between control panel assembly
unrts.
Procedure I.
Replace or repair wiring.
Defective control unit. Procedure J.
Display does not operate properly Defective key unrt. Procedure J.
when STOP/CLEAR key is touched. ’
(Buzzer should sound and time of Defective stop switch. Procedure E.
day should appear in display.) Defective control unit. Procedure J.
Oven lamp does not light with Defective oven lamp. -_
door opened. Replace oven lamp.
Defective stop switch. Procedure E.
Defective control unit. Procedure J.
Open or loose wire connection to the above Check wiring.
components.
COOKING CONDITION
Oven lamp does not light in cook
cycle.
(Do light when door is opened.)
Defective relay RY-1 on control unit. Procedure J.
I
I
7
R-9380
TROUBLESHOOTING GUIDE (CONT’D)
PROBLEM POSSIBLE CAUSE TEST PROCEDURE OR
CORRECTION
Oven lamp does not light at all. Burned out bulb.
Cook indicator appears jn display but
turntable motor does not operate.
Oven lamp lights but fan motor
does not operate.
(Turntable motor does operate)
Oven does not go into cook cycle
when INSTANT COOK/START
key 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)
C
Defective magnetron.
Defective relay RY-2 on control unit.
Defective power transformer.,
Defective rectifier.
Defective high voltage capacitor.
Defective control unit.
Open or loose wiring to the above
components.
Turntable motor does not operate.
r
Oven does not cook properly when
cooking control set to LOW, MED
LOW, MED, MED HIGH cooking
powers.
Defective control unit.
(Operates properly on HIGH.)
Defective key unit.
Open or loose wiring between, the above
components.
8
COOKING CONDITION (CONT’D)
Open wiring to oven lamp socket.
Defective relay RY-1 on control unit.
Turntable motor defective.
Open or loose wiring between control
. unit and motor.
Defective fan motor.
Open or loose wiring to fan motor.
Upper and Lower latch switches and stop
switch defective or out of adjustment.
Blown fuse M6.3A.
Defective temp. fuse.
Defective thermal cut-out.
Defective relay RY-1, RY-2 on control unit.
Defective control unit.
Defective key unit.
Open or loose wiring to the above
components.
Replace oven lamp.
Check and repair wiring.
Procedure J.
Replace motor.
Check and repair wiring.
Replace fan motor.
Check and repair wiring.
Procedure E.
Procedure H.
Procedure F.
Procedure I.
Procedure J.
Procedure J.
Procedure J.
Check and repair wiring.
Procedure A.
Procedure J.
Procedure 8.
Procedure C.
Procedure D.
zii?czs
Replace turntable motor.
Procedure J.
R-9380
PROBLEM
EASY DEFROST condition touching
INSTANT COOK/START Pad,
“ERROR” appears.
POSSIBLE CAUSE TEST PROCEDURE OR
CORRECTION ’
Programmed incorrectly EASY DEFROST will only operate
on a specific weight.
Range for each food category.
See steps for Easy Defrost is
Operation Manual.
Defective control unit. Procedure J.
R-9380
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
A MAGNETRON ASSEMBLY TEST
DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPO-
NENTS 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
Microwave 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;
Pxt/4.2=;Vx LIT
P (W) = 4.2 x V x AT I t
Our condition for the water load is as follows:
Water load .. 2000 ml, Heating time ...I 20 seconds
P-70x 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 120 seconds
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 satis-
factory, execute the measurement several times and judge the result from the synthetic point
of view. Microwave output power should be within + 15% of the nominal one.
Calculation of output power;
Microwave output po\iver ...P (W) = 70 x AT ( “C)
AT = ( ATL + ATR) / 2 : average temperature rise
ATL = (TL2 - TLI), ATR = (TR2 - TRl)
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 mer-
cury thermometer is recommended.
IO
TEST PROCEDURES (CONT’D)
PROCEDURE
LETTER COMPONENT TEST
3. Water container should be one (1) litre beaker made of Pyrex glass and its diameter approxi-
mately 12 cm.
B
4. Room temperature should be around 20 “C.
5. Power supply voltage should be specification voltage.
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 1.66 ohms and the resistance of the high voltage coil
should b approximately 84 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 COMPO-
NENTS 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 di-
rections, the rectifier is probably defective and should be replaced. ~RD62501 U)
D 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 approximately IOM R once the capacitor is
charged. If the above is not the case, check the capacitor with an ohmmeter to see if it is shorted
between the terminals. If it is shorted, replace the capacitor.
E
(RD82603U)
SWITCH TEST
Isolate the switch and check the contacts by using an ohmmeter using the following table
If improper operation is indicated, make the necessary switch adjustment or replacement.
Plunger released
Closed circuit ----_-.-L ._.._..___._ _ _~ ~~~_..._
Open circuit
11
R-9380
TEST PROCEDURES (CONT’D)
PROCEDURE
LETTER COMPONENT TEST
F TEMP. FUSE TEST
A continuity check across the temp. fuse terminals should indicate a closed circuit unless the
temperature of the temp. fuse reaches approximately 115 “C.
An open magnetron temp. fuse indicates overheating of the magnetron assembly. If the temp.
fuse indicates a open circuit, replace the temp. fuse and check for restricted air flow to the
magnetron through the opening in the chassis, especially the air duct and fan motor.
G MONITOR SWITCH TEST
Desconnect oven from power supply cord. Before performing this test, make sure that the upper
latch switch and lower latch switch are operating properly referring to the above Switch Test
Procedure.
Disconnect the wire lead from the upper latch switch (NO) terminal.
Check the monitor switch operation by using the ohmmeter as follows.
When the door is open, the meter should indicate a closed circuit.
When the monitor switch actuater is pushed by a screw driver through the lower 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, the switch may be defective.
After testing the monitor switch, re-connect the wire lead to the upper latch switch (NO) termi-
nal.
POWER TRANSFORMER
OHMMETER
MONITOR
SWITCH
H BLOWN OVEN FUSE
If the oven fuse in the upper latch switch-monitor switch circuit is blown when the door is
opened, check the upper latch switch and monitor switch before replacing the blown fuse.
If the oven fuse is blown by improper switch operation, replace the defective switch and oven
fuse at the same time.
Replace just the oven fuse if the switches operate normally.
CAUTION; REPLACEMENT FUSE MUST BE THE LISTED FUSE IN PARTS LIST.
I THERMAL CUT-OUT TEST
A continuity check across the thermal cut-out terminals should indicate a closed circuit. If the
temperature of the steam duct reaches approximately 115 “C the thermal cut-out opens.
The termal cut-out resets automatically at below -20 “C.
An open thermal cut-out indicates overheating of the oven cavity. Check for restricted air flow
to the magnetron through the opening in the chassis, especially the cooling duct and fan.
CAUTION; IF THE THERMAL CUT-OUT INDICATES OPEN CIRCUIT, REPLACE THE THER-
MAL CUT-OUT.
12
R-9380
TEST PROCEDURES (CONT’D)
PROCEDURE
LETTER COMPONENT TEST
J 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 two units Control Unit and Key Unit and troubleshooting by unit replacement is de-
scribed according to the symptoms indicated.
I. Key Unit.
The following symptoms indicate a defective key unit. Replace the key unit.
a) When touching the pads, a certain pad produces no signal at all.
b) When touching a number pad, two figures or more are displayed.
c) When touching the pads, sometimes a pad produces no signal.
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 a signal.
2-2 In connection with indicators
a) At a certain digit, all or some segments do not light up.
b) At a certain digit, brightness is low.
c) Only one indicator does not light 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 ficker.
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.
13
R-9380
TEST PROCEDURES (CONT’D)
PROCEDURE
LETTER COMPONENT TEST
K PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING
BOARD(PWB) IS OPEN.
To protect the electronic circuits, this model is provided with a fine foil pattern added to the
primary on the PWB, and this fine pattern service as a substitute coil. If the foil pattern is open,
follow the troubleshooting guide given below for repair.
Problem: POWER ON, indicator does not light up.
ISTEPS I OCCURANCE CAUSE OR CORRECTION
1 The rated voltage is not applied to POWER terminal Check supply voltage and oven main unit.
of CPU connector (CN-A)
2 The rated voltage.is applied to primary side of power Power transformer or secondary circuit defective.
transformer. Check and repair.
3 Only pattern at “a” is broken. ‘Insert jumper wire 31 and solder.
4 Pattern at “a” and “b” are broken. *Insert the coil RCILF2003YAZZ between “c” and
“d”.
NOTE:* At the time of these repairs, make visual in-
spection of the varistor for burning damage
and examine the transformer with tester for the
presence of layer short-circuit (check primary
coil resistance).
If any abnormal condition is detected, replace
the defective parts.
*; _-” :‘ i
.:, ‘I ^ x ^,
&u+$ ,‘i
*; _, L.,, I :, rLlr
‘** ,.^ ,;‘;’ ‘-1: >:; G&, :p;e
.‘?,‘.,I:, “I ;,, :“\ @ N _ A VRS$
i_ ,,
,<:g;;; 3 P
,&:?;,:,g,I ‘,px*&;&; 2a=,,,,-*;$‘;
.,,, _,’
:
(RD8: KO4U)
14
TOUCH CONTROL PANEL ASSEMBLY
OUTLINE OF TOUCH CONTROL PANEL
The touch control section consists of the following
units as shown in the touch control panel circuit.
(1) Key Unit
(2) Control Unit
The principal functions of these units and the signals
communicated among them are explained below.
(RD91 lA3U)
Key Unit
The key unit is composed of a matrix, signals generated
in the LSI are sent to the key unit through P62, P63
and P70- P73.
-..-. .- -
When a key pad is touched, a signal is completed
through the key unit and passed back to the LSI
through PIO-PI3 to perform the function that was re-
quested.
Control Unit
Control unit consists of LSI, power source circuit,
synchronizing signal circuit, ACL circuit, buzzer circuit
and indicator circuit. (RD915BlU)
1)
2)
3)
LSI
This LSI controls the key strobe signal, relay driving
signal for oven function and indicator signal.
(RD916Al U)
Power Source Circuit
This circuit generates voltage necessary in the
control unit.
Svmbol Voltaae Aoolication
VDD -12v LSI (ICI ), ACL circuit
VREF -6.15V LSI (ICI)
VP -26.5V Fluorescent display tube : Grid
and anode voltage
VF+ -15.2V F$rrent of fluorescent display
VF- (VF+ to VF- voltage: AC 3.5V)
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
4) ACL Circuit
A circuit to generate a signal which resets the LSI
to the initial state when power is supplied. (RDSl SAl U)
5) Buzzer Circuit
The buzzer is responsive to signals from the LSI
to emit noticing sounds (key touch sound and
completion sound).
6) Stop Switch
A switch to “tell” the LSI if the door is open or
closed. (RD91 BA2U)
7) Relay Circuit
To drive the magnetron, fan motor, turntable motor
and light the oven lamp.
8) Indicator Circuit
(RD91 AA1 U)
(RD91 CB2U)
Indicator element is a Fluorescent Display.
Basically, 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 6-digits, 13-segments are
used for displaying figures. (RD91 DA1 U)
I
I
on commercial frequency. (RD918Al U)
15
R-9380
DESCRIPTION OF LSI
LSI(IZA135DR)
The I/O signal of the LSI(IZA135DR) is detailed in the following table. (RD93101 U)
I
.PINNO~~~.i1~~~~~..-~--.-_--~.__l~SIGIUAL_i~~~~3~--_
I I/O
- j OUT
Segment data siqnals.
Refer to the touch control panel circuit for the relationship between signals and indicators.
Normally, one pulse is output in every synchronized signal period, and input to the anode of the fluorescent drsplax.
(RD939Al )
PIN NO. ’ 5
----i-- -~~
Auto clear terminal..
SIGNAL j ACL 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. (RD93MAZU)
PIN NO. / 6 SIGNAL ) CL1 1 I/O
/-- / IN
~-- .-
Internal clock oscillation frequencv input settina.
The internal clock frequency is set by inserting the ceramic filter oscillation circuit with respect to CL2 terminal.
(RD93EA2U)
PIN NO. 1 7 1 SIGNAL j CL2
------?-- --~ --
Internal clock oscillation frequencv control output.
Output to control oscillation input of CL1
I I/O 1 OUT
(RD93EAl U)
PIN NO. 1 8
~--.--
Segment data siqnal.
Signal similar to P30.
SIGNAL / P40 I I/O I
I OUT
(RD939A2U)
PIN NO. 1 9
__l. ~~~-~~_. ._~~~~~.~_.___ SIGNAL ’ TEST
~~~---... --1--- --.--..-. ~~~--
Terminal not used. Connected to VDD. I I/O 1 IN
(RD93KA4U)
PIN NO. j IO-13
Segment-bata signal.
Signal similar to P30.
SIGNAL / P41 -P43,P50 I I/O OUT
(RD939A2U)
PIN NO. 1 14
~~~ --!- - .~ SIGNAL 1 P5l
-----L- ~-~~~- .._~ ._________._ I/O 1 IN ___- -
Terminal to change functions according to the model.
Signal in accordance with the model in operation is applied to set up its function. (Rd93JAl U)
PIN NO. I 15
Terminal not used.
SIGNAL ; P52 ---~~-...---...~~--
-~--~
(RD93KA2U)
16
R-9380
PIN NO. / 16 1 SIGNAL / P53 I I/O j IN
e.-i_----- ~.-.--~_~~. -..-~
Terminal for manufacture test.
Normally terminal not used. (FiD931A3U)
PIN NO. 1 17,16 1 SIGNAL j P6o,P61 I/O j IN
---
Terminal not used. (RD93KA2U)
PINNO. 119 1 SIGNAL / P62 I/O : OUT
--___- _yi-----.---.
Kev strobe siqnal.
Signal applied to touch-key section.
A pulse signal is input to Pl O-P1 3 terminal while one of D-l line keys on key matrix is touched. CRD93EAl U)
PIN NO. 1 20
Kev strobe signal.
1 SIGNAL j P63 I/O 1 OUT
-./ -.
Signal applied to touch-key section.
A pulse signal is input to PIO-PI3 terminal while one of D-2 line keys on key matrix is touched. (RD93BAl U)
PIN NO. j 21 1 SIGNAL / P70 I l/O I OUT
Kev strobe signal.
Signal applied to touch-key section.
A pulse signal is input to PlO-P13 terminal while one of D-3 line keys on key matrix is touched. (RD93BAl U)
PIN NO. 1 22 1 SIGNAL 1 P71 I I/O : OUT
Kev strobe signal.
Signal applied to touch-key section.
A pulse signal is input to PIO-PI3 terminal while one of D-4 line keys on key matrix is touched. / RD93BAl Ub
PIN NO. / 23 1 SIGNAL / P72 I I/O ! OUT
Kev strobe siQnal.
Signal applied to touch-key section.
A pulse signal is input to PIO-P13 terminal while one of D-5 line keys on key matrix is touched. (RD93BAl U)
PIN NO. j 24 SIGNAL I P73 I/O 1 OUT
jam~--.~.~~~~~. ~~~
___._~
Kev strobe signal.
Signal applied to touch-key section.
A pulse signal is input to PIO-PI3 terminal while one of D-6 line keys on key matrix is touched. (RD93BAl U)
PIN NO. i 25
Terminal not used.
._
SIGNAL i KT I/O ’ IN
iRD93KA2IJ)
PIN NO. / 26 1 SIGNAL / KI 1 I/O IN
_----.-----. -...--.~_ -~ --~ _ ~~-. .-. -.
Siclnal svnchronized with commercial source frequencv(50Hz).
This is the basic timing for time processing of LSI. !RD93FEl U:
17
R -9380
I
PIN NO. 1 27 SIGNAL 1 SO I I/O j OUT
Sinnal to sound buzzer.
A: Key touch sound (0.12 sec.).
B: Completion sound (2.4 sec.j. (RD93LAl U)
PIN NO. / 28
__-__ 1 SIGNAL j NC I I/O /NC
Terminal not used. (RD93KAZU)
PIN NO. / 29 SIGNAL / VDD I I/O
- / IN
Power source voltaoe: -12V.
VDD voltage of power source circuit input. (RD93GAl U)
PIN NO. / 30 ---__ I -SIGNAL / ~80 I/O i OUT
Terminal not used. (RD93KA2U)
PIN NO. 31
Terminal not used.
SIGNAL I P81 I l/O 1 IN
(RD93KA2U)
PIN NO. 1 32 1 SIGNAL ! GND I I/O / IN
Connected to GND. (RD93KAl U)
-PINNo. i .33--.-.-...----__.~~~~~--.-sl!L p82
Terminal not used. Connected to GND. I l/O / OUT
(RD93KA5U)
PIN NO. I 34 SIGNAL i P83
__-
Terminal not used. Connected to GND. I l/O 1 OUT
(RD93KA5U)
PIN NO. 135-38 SIGNAL j P90-P93
--
Terminal not used. Connected to GND. I I/O 1 OUT
(RD93KA5U)
PIN NO. 1 SIGNAL 1 PO0j 39
Terminal not used. Connected to GND. I I/O / IN
(RD93KAW)
..‘NNO.i_~~--~---lSIGNAL I po1 I/O 1 IN
Terminal to chanqe functions according to the model.
By using the A/D converter contained in the LSI. DC voltage in accordance with the model in operation is applied
to set up its function. (Rd93JA2U)
pt.~~N0,-.i~41-..--~--- .____ -- .SIGAL i po2
Terminal not used. Connected to GND. I I/O IN
(RD93KA5U)
18
PIN NO. j 42 1 SIGNAL / PO3 I I/O / IN
Terminal to chanqe functions accordinq to the model.
By using the A/D converter contained in the LSI. DC voltage in accordance with the model in operation is applied
to set up its function. (Rd93JAZU)
PIN NO. / 43 1 SIGNAL 1 PI0 I/O j IN
_-__ ~~~_ ~~~~~.I~~-~~~-----~~ _.._ ~_
Siqnal cominq from touch key.
When either one of D-l 1 line keys on key matrix is touched, a corresponding signal out of P70-P73,P63 and P62
will be input into PIO.
When no key is touched, the signal is held at “L” level. (RD93CAl U)
PIN NO. 1 44 1 SIGNAL / PI1 I/O / IN
Siqnal cominq from touch key.
When either one of D-l 0 line keys on key matrix is touched, a corresponding signal will be input into PI lI;UgsCAZ,,j
PIN NO. j 45 1 SIGNAL / PI2 I/O
- i IN
Siqnal cominq from touch kev.
When either one of D-9 line keys on key matrix is touched, a corresponding signal will be input into PI 2.
(RD53CAZU)
PIN NO. 1 46 1 SIGNAL 1 PI3 ~~m~mL.--!/o..-.-.iIN____.~~~~~~~_.. .._
Siqnal cominq from touch ,kev.
When either one of D-8 line. keys on key matrix is touched, a corresponding signal will be input into PI 3.
(RD93CAZU)
PIN NO. / 47
Connected to GN D.
/
SIGNAL j AGND l/O ! IN
_~- i -.~-~-~.~._.--~.- .--. .-~ ---.. I
(RD93KAl U)
PIN NO. / 48-53
Diqit selection siqnal.
1 SIGNAL ; PA9-PA4 I .---- L-~~~
l/O I OUT
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 fluorescenti$~;$qj
PIN NO. j 54 1 SIGNAL / PA3 L-.-. ----
l/O OUT
I. -..- --. ...-1 -. ~~_. ~~
Oven lamp, turntable motor and coolinq fan motor drivinq signal. (Square Waveform: 50Hz)
To turn on and off the control relay.
The pulse signal (50Hz) is delivered to the control relay driving circuit and cook relay control circuit. cRDY32El U)
PIN NO. /55 SIGNAL ; PA2
Magnetron Hinh-voltane circuit drivinn sinnal.
To turn on and off the cook relay.
I/O OUT
In HGH operation, the signals holds “H” level during microwave cooking and “L” 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. 1,RD933Al ii)
19

Other Sharp Microwave Oven manuals

Sharp R-551ZS User manual

Sharp

Sharp R-551ZS User manual

Sharp Carousel R-340R User manual

Sharp

Sharp Carousel R-340R User manual

Sharp R-342H User manual

Sharp

Sharp R-342H User manual

Sharp R-939 User manual

Sharp

Sharp R-939 User manual

Sharp Carousel R-930CS User manual

Sharp

Sharp Carousel R-930CS User manual

Sharp R-450B User manual

Sharp

Sharp R-450B User manual

Sharp Carousel RK56S27 User manual

Sharp

Sharp Carousel RK56S27 User manual

Sharp R-580D User manual

Sharp

Sharp R-580D User manual

Sharp R652BK User manual

Sharp

Sharp R652BK User manual

Sharp R-8740M User manual

Sharp

Sharp R-8740M User manual

Sharp Carousel R1874TY User manual

Sharp

Sharp Carousel R1874TY User manual

Sharp R-85STM-A User manual

Sharp

Sharp R-85STM-A User manual

Sharp R-320DK User manual

Sharp

Sharp R-320DK User manual

Sharp R-26ST-A User manual

Sharp

Sharp R-26ST-A User manual

Sharp R-204 User manual

Sharp

Sharp R-204 User manual

Sharp R-899P User manual

Sharp

Sharp R-899P User manual

Sharp R-8000G User manual

Sharp

Sharp R-8000G User manual

Sharp YC-PC254A User manual

Sharp

Sharp YC-PC254A User manual

Sharp R-209BW User manual

Sharp

Sharp R-209BW User manual

Sharp SMC1842CS-CR User manual

Sharp

Sharp SMC1842CS-CR User manual

Sharp R-239 Instruction Manual

Sharp

Sharp R-239 Instruction Manual

Sharp R-890E W Installation manual

Sharp

Sharp R-890E W Installation manual

Sharp R-420CK User manual

Sharp

Sharp R-420CK User manual

Sharp YC-MS252A User manual

Sharp

Sharp YC-MS252A User manual

Popular Microwave Oven manuals by other brands

Frigidaire PLMV178HC Service manual

Frigidaire

Frigidaire PLMV178HC Service manual

Whirlpool MW7500XW Use and care guide

Whirlpool

Whirlpool MW7500XW Use and care guide

GE PEM31 owner's manual

GE

GE PEM31 owner's manual

AEG KM8403001 user manual

AEG

AEG KM8403001 user manual

GE JES0736 manual

GE

GE JES0736 manual

Goldstar MV-1401W Owner's manual & cooking guide

Goldstar

Goldstar MV-1401W Owner's manual & cooking guide

Panasonic NN-963WF Service manual

Panasonic

Panasonic NN-963WF Service manual

Dacor DMO2420B Use and Installation Instructions

Dacor

Dacor DMO2420B Use and Installation Instructions

Samung GE731K user manual

Samung

Samung GE731K user manual

Westinghouse WCM14110SSGZ user manual

Westinghouse

Westinghouse WCM14110SSGZ user manual

Goldstar MV-1725B Owner's manual & cooking guide

Goldstar

Goldstar MV-1725B Owner's manual & cooking guide

Kuppersberg TMW 200 X manual

Kuppersberg

Kuppersberg TMW 200 X manual

Whirlpool AMW 732 Installation, quick start

Whirlpool

Whirlpool AMW 732 Installation, quick start

Proline CB200 operating instructions

Proline

Proline CB200 operating instructions

Vitek Crystal VT-1653 Manual instruction

Vitek

Vitek Crystal VT-1653 Manual instruction

Saturn ST-MW7159GR K manual

Saturn

Saturn ST-MW7159GR K manual

Whirlpool AMW 712 Installation, quick start

Whirlpool

Whirlpool AMW 712 Installation, quick start

Miele M 635 EG operating instructions

Miele

Miele M 635 EG operating instructions

manuals.online logo
manuals.online logoBrands
  • About & Mission
  • Contact us
  • Privacy Policy
  • Terms and Conditions

Copyright 2025 Manuals.Online. All Rights Reserved.