Sharp R-508FS User manual

R-508FS
In the interest of user-safety the oven should be restored to its original condition and only parts identical to those specified
should be used.
WARNINGTOSERVICEPERSONNEL:Microwaveovenscontaincircuitrycapableofproducingveryhighvoltageand
current,contactwithfollowingpartsmayresultinasevere,possiblyfatal,electricalshock.(HighVoltageCapacitor,
High Voltage Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc..)
TABLEOF CONTENTS Page
PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO
AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY.................. INSIDE FRONT COVER
BEFORE SERVICING..................................................................................................... INSIDE FRONT COVER
WARNING TO SERVICE PERSONNEL .............................................................................................................. 1
MICROWAVE MEASUREMENT PROCEDURE .................................................................................................. 2
FOREWORD AND WARNING............................................................................................................................. 3
PRODUCT SPECIFICATIONS............................................................................................................................. 4
GENERAL INFORMATION ................................................................................................................................. 4
TESTPROCEDURE ..............................................................................................................................................6
CPUUNITCIRCUIT ................................................................................................................................................8
PARTSLIST...........................................................................................................................................................9
PACKINGANDACCESSORIES ..........................................................................................................................13
S52M188R508FE
R-508FS
MICROWAVEOVEN
MODEL
SUPPLEMENTALSERVICEMANUAL
SHARP ELECTRONCS CORPORATION This document has been published to be used for after
sales service only.
The contents are subject to change without notice.
Service Headquarters: Sharp Plaza, Mahwah, New Jersey, 07430-2135
R-508FS
This is a supplemental Service Manual for model R-508FS.
This model is quite simular to base models R-510FK/FW (S12M182R510FE).
Use this supplemental manual together with the base model Service Manual for complete operation and service information.

R-508FS
PRECAUTIONS TO BE OBSERVED BEFORE AND
DURING SERVICING TO AVOID POSSIBLE
EXPOSURE TO EXCESSIVE MICROWAVE
ENERGY
(a) Donotoperate or allow theovento be operated withthe door open.
(b) Make the following safety checks on all ovens to be serviced before activating the magnetron or other
microwavesource, andmakerepairs asnecessary: (1)interlock operation,(2)proper doorclosing, (3)
sealand sealingsurfaces(arcing, wear,and otherdamage),(4) damageto orloosening of hingesand
latches,(5) evidence ofdropping or abuse.
(c) Before turningonmicrowave power forany service test orinspection within the microwavegenerating
compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment,
integrity,andconnections.
(d) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation
and transmission systems shall be repaired, replaced, or adjusted by procedures described in this
manualbeforethe oven is releasedtothe owner.
(e) A microwave leakage check to verify compliance with the Federal Performance Standard should be
performedon eachoven priortorelease tothe owner.
BEFORE SERVICING
Before servicing an operative unit, perform a microwave emission check as per the
Microwave Measurement Procedure outlined in this service manual.
If microwave emissions level is in excess of the specified limit, contact SHARP
ELECTRONICSCORPORATIONimmediately @1-800-237-4277.
If the unit operates with the door open, service person should 1) tell the user
not to operate the oven and 2) contact SHARP ELECTRONICS CORPORATION and Food and
Drug Administration's Center for Devices and Radiological Health immediately.
Service personnel should inform SHARP ELECTRONICS CORPORATION of any certified unit
found with emissions in excess of 4mW/cm2. The owner of the unit should be instructed
not to use the unit until the oven has been brought into compliance.

1
R-508FS
WARNING TO SERVICE PERSONNEL
Microwave ovens contain circuitry capable of pro-
ducing very high voltage and current, contact with
following parts
may result in a severe, possibly
fatal, electrical shock.
(Example)
HighVoltageCapacitor,HighVoltagePowerTrans-
former,Magnetron,HighVoltageRectifierAssem-
bly, High Voltage Harness etc..
Read the Service Manual carefully and follow all
instructions.
Before Servicing
1. Disconnect the power supply cord , and then
remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
WARNING:RISK OF ELECTRIC SHOCK.
DISCHARGE THE HIGH-VOLTAGE
CAPACITOR BEFORE SERVICING.
The high-voltage capacitor remains charged about 60
secondsaftertheovenhasbeenswitchedoff.Waitfor60
secondsandthenshort-circuittheconnectionofthehigh-
voltagecapacitor (thatis theconnecting leadof thehigh-
voltage rectifier) against the chassis with the use of an
insulated screwdriver.
Whenever troubleshooting is performed the power supply
mustbedisconnected.Itmay,in somecases,benecessary
to connect the power supply after the outer case has been
removed, in this event:
1. Disconnect the power supply cord, and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the leads to the primary of the power
transformer.
5. Ensure that the leads remain isolated from other
components and oven chassis by using insulation tape.
6. After that procedure, reconnect the power supply cord.
When the testing is completed,
1. Disconnect the power supply cord, and then remove
outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Reconnect the leads to the primary of the power
transformer.
5. Reinstall the outer case (cabinet).
6. Reconnectthe power supplycord aftertheouter caseis
installed.
7. Run the oven and check all functions.
After repairing
1. Reconnect all leads removed from components during
testing.
2. Reinstall the outer case (cabinet).
3. Reconnectthe power supplycord aftertheouter caseis
installed.
4. Run the oven and check all functions.
Microwaveovensshouldnot beoperatedempty.To testfor
the presence of microwave energy within a cavity, place a
cup of cold water on the oven turntable, close the door and
set the power to HIGH and set the microwave timer for two
(2) minutes. When the two minutes has elapsed (timer at
zero) carefully check that the water is now hot. If the water
remainscoldcarryoutBeforeServicing procedureandre-
examine the connections to the component being tested.
When all service work is completed and the oven is fully
assembled,themicrowavepoweroutputshouldbechecked
and a microwave leakage test should be carried out.
Don't Touch !
Danger High Voltag
e

2
R-508FS
MICROWAVE MEASUREMENT PROCEDURE
A. Requirements:
1) Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a microwave oven
shouldnotexceed1mW/cm2atanypoint5cmormorefromtheexternalsurfaceoftheoven,measuredpriortoacquisition
byapurchaser,andthereafter (throughtheusefullifeof theoven),5 mW/cm2atany point5cmormorefrom theexternal
surface of the oven.
2) Safety interlock switches:
Primary interlock relay switch shall prevent microwave radiation emission in excess of the requirement as above
mentioned. Secondary interlock relay and door sensing switch shall prevent microwave radiation emission in excess of
5 mW/cm2 at any point 5cm or more from the external surface of the oven.
B.Preparationfortesting:
Beforebeginningtheactualmeasurementof leakage,proceedasfollows:
1) Make sure that the actual instrument is operating normally as specified in its instruction booklet.
Important:
Survey instruments that comply with the requirement for instrumentation as prescribed by the performance standard for
microwave ovens, 21 CFR 1030.10(c)(3)(i), must be used for testing.
2) Place the oven tray in the oven cavity.
3) Place the load of 275±15 ml (9.8 oz) of tap water initially at 20±5O C (68OF) in the center of the oven cavity.
Thewatercontainer shallbealowformof600ml(20oz)beakerwithaninsidediameterofapprox. 8.5cm(3-1/2 in.)and
made of an electrically nonconductive material such as glass or plastic.
Theplacingof thisstandardload in theoven is importantnot only toprotectthe oven, butalso to insurethat any leakage
is measured accurately.
4) Set the cooking control on Full Power Cooking Mode.
5) Closethedoorandselectacookcycleofseveralminutes.Ifthewaterbeginstoboilbeforethesurveyiscompleted,replace
it with 275 ml of cool water.
C. Leakage test:
Closed-door leakage test (microwave measurement):
1) Grasptheprobeofthesurveyinstrumentandholditperpendiculartothegapbetweenthedoorandthebodyoftheoven.
2) Movetheprobeslowly,notfasterthan1in./sec.(2.5cm/sec.)alongthegap,watchingforthemaximumindicationonthe
meter.
3) Checkforleakageatthedoorscreen,sheetmetalseamsandotheraccessiblepositionswherethecontinuityofthemetal
has been breached (eg., around the switches, indicator, and vents).
Whiletestingforleakagearoundthedoor,pullthedoorawayfromthefrontoftheovenasfarasispermittedbytheclosed
latch assembly.
4) Measurecarefullyatthepointofhighestleakageandmakesurethatthehighestleakageisnogreaterthan4mW/cm2,and
that the primary interlock switch/secondary interlock relay does turn the oven OFF before any door movement.
NOTE: After servicing, record data on service invoice and microwave leakage report.

3
R-508FS
SHARP ELECTRONICS CORPORATION
SHARP PLAZA, MAHWAH,
NEW JERSEY 07430-2135
SUPPLEMENTAL
SERVICE MANUAL
MICROWAVEOVEN
R-508FS
FOREWORD
ThisManualhasbeenpreparedtoprovideSharpElectronicsCorp.Service
Personnel with Operation and Service Information for the SHARP
MICROWAVEOVEN,R-508FS.
The model R-508FS is quite similar to base models R-510FK/FW
(Ref.# S12M188R508FE)
Itisrecommendedthatservicepersonnelcarefullystudytheentiretextof
this manual so that they will be qualified to render satisfactory customer
service.
Checktheinterlockswitchesandthedoorsealcarefully.Specialattention
shouldbegiventoavoidelectricalshockandmicrowaveradiationhazard.
WARNING
Never operate the oven until the following points are ensured:
(A) The door is tightly closed.
(B) The door brackets and hinges are not defective.
(C) The door packing is not damaged.
(D) The door is not deformed or warped.
(E) There is no other visible damage with the oven.
Servicing and repair work must be carried out only by trained service
personnel. DANGER
Certain initial parts are intentionally not grounded and present
ariskofelectrical shock only duringservicing.Serviceperson-
nel - Do not contact the following parts while the appliance is
energized;
High Voltage Capacitor, Power Transformer, Magnetron, High
Voltage Rectifier Assembly, High Voltage Harness;
If provided, Vent Hood, Fan assembly, Cooling Fan Motor.
All the parts marked “*” on parts list are used at voltages more than
250V.
Removal of the outer wrap gives access to voltage above 250V.
All the parts marked “∆” on parts list may cause undue microwave
exposure, by themselves, or when they are damaged, loosened or
removed.
PRODUCTDESCRIPTION
GENERALINFORMATION
OPERATION
TROUBLESHOOTINGGUIDEAND
TESTPROCEDURE
PARTS LIST

4
R-508FS
GENERAL INFORMATION
GROUNDING INSTRUCTIONS
This oven is equipped with a three prong grounding plug. It must be plugged into a wall receptacle that is properly installed
and grounded in accordance with the National Electrical Code and local codes and ordinances.
Intheeventofanelectricalshortcircuit,groundingreducestheriskofelectricshockbyprovidinganescapewirefortheelectric
current.
WARNING: Improper use of the grounding plug can result in a risk of electric shock.
ElectricalRequirements
The electrical requirements are a 120 volt 60 Hz, AC only,
15or20amp.fusedelectricalsupply.Itisrecommendedthataseparatecircuitservingonlythisappliancebeprovided.When
installing this appliance, observe all applicable codes and ordinances.
A short power-supply cord is provided to reduce risks of becoming entangled in or tripping over a longer cord.
Whereatwo-prongedwall-receptacleisencountered,itisthepersonalresponsibilityandobligationofthecustomertocontact
SPECIFICATION
ITEM DESCRIPTION
PowerRequirements 120 Volts
14.3Amperes, 1700 watts
60Hertz
Singlephase,3wiregrounded
PowerOutput 1200watts(IEC705 TESTPROCEDURE)
Operatingfrequencyof2450MHz
CaseDimensions Width 24"
Height 13-3/8"
Depth 19-1/8"
CookingCavityDimensions Width 17-3/8"
Height 10-1/2"
2.0 Cubic Feet Depth 18-5/8"
ControlComplement TouchControl System
Clock ( 1:00 - 12:59 )
Timer (0 - 99 min. 99 seconds)
MicrowavePowerforVariableCooking
Repetition Rate;
P-HI .................................................. Fullpowerthroughoutthe cookingtime
P-90 ....................................................................approx. 90% of Full Power
P-80 ....................................................................approx. 80% of Full Power
P-70 ....................................................................approx. 70% of Full Power
P-60 ....................................................................approx. 60% of Full Power
P-50 ....................................................................approx. 50% of Full Power
P-40 ....................................................................approx. 40% of Full Power
P-30 ....................................................................approx. 30% of Full Power
P-20 ....................................................................approx. 20% of Full Power
P-10 ....................................................................approx. 10% of Full Power
P-0 ......................................................Nopowerthroughoutthecookingtime
MINUTE PLUS pad, Cook center pads, Defrost center pads, Number selection
pads,PowerLevel pad,Timer/Clockpad,Stop/Clearpad, START pad,Keep
warm,HotWater,ReheatandPopcorn.
Oven Cavity Light Yes
SafetyStandard UL Listed FCC Authorized
DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J

5
R-508FS
a qualified electrician and have it replaced with a properly grounded
three-pronged wall receptacle or have a grounding adapter properly
groundedandpolarized.Iftheextensioncordmustbeused,itshouldbe
a 3-wire, 15 amp. or higher rated cord. Do not drape over a countertop
ortablewhereitcanbepulledonbychildrenortrippedoveraccidentally.
CAUTION: DO NOT UNDER ANY CIRCUMSTANCES CUT OR RE-
MOVE THE ROUND GROUNDING PRONG FROM THIS
PLUG.
OVEN DIAGRAM
1. One touch door open button.
Push to open door.
2. Door latches.
The oven will not operate unless the
door is securely closed.
3. Removable turntable support.
4. Removable turntable.
The turntable will rotate clockwise or
counterclockwise.
5. Oven lamp.
It will light when oven is operating or
door is opened.
6. Oven door with see-through window.
7. Ventilation openings. (Rear)
8. Auto-Touch control panel.
9. Time display: Digital display, 99
minutes 99 seconds.
10.Wave guide cover.
11.Power supply cord
TOUCH CONTROL PANEL
3-Pronged
Plug
Grounded
Receptacle Box
Grounding Pin
3-Pronged Receptacle
NOTE:
The directed features are disa-
bled after one minute when the
ovenisnotin use.Thesefeatures
are automatically enabled when
the door is opened and closed or
theSTOP/CLEARpadispressed.
R-508FS
1
65
4
210
11
9
7
8
3

6
R-508FS
Key Unit
TEST PROCEDURES
PROCEDURE
LETTER COMPONENTTEST
JKEYUNITTEST
1.Disconnectthe power supplycord,and then removeoutercase.
2. Open the door and block it open.
3.Dischargehighvoltagecapacitor.
4. Isolate the key unit with the control panel frame to be tested.
5. Using an ohmmeter and referring to the key unit matrix indicated on the control unit circuit, check the
circuit between the pins of the key unit that correspond to the STOP/CLEAR pad. When the pad is
pressed,theohmmetershouldindicateshortcircuit.Whenthepadisreleased,theohmmetershould
indicateopencircuit.Ifincorrectreadingsareobtained,thekeyunitisfaultyandmustbereplaced.About
theother pads, theabovemethod may beused
6. Reconnect all leads removed from components during testing.
7. Re-install the outer case (cabinet).
8. Reconnect the power supply cord after the outer case is installed.
9. Run the oven and check all functions.
8
POPCORN
DE FR OS T
START
POWER
LE VE L
MINUT E
PLUS
TIMER
CLOCK
1
4
7
5
2
8
0
9
3
6
COOK
REHEAT
7 6 5 4 3 2 1
91011121314
STOP
CLEAR

7
R-508FS
WARNING : The oven should be fully assembled before following procedure.
(1) Place one cup of water in the center of the turntable tray in the oven cavity.
(2) Close the door, touch the “ DEFROST “ pad once.
(3) Touch the number pad “ 2 “ and then touch the number pad “ 5 “.
(4) Touch the start pad.
(5) TheovenisinCompuDefrostcookingcondition.
(6)Theovenwilloperate asfollows.(incaseof Steak/Chops0.5lb)
WEIGHT 1ST STAGE 2ND STAGE
0.5lb LEVEL TIME LEVEL TIME
60% 57sec. 40% 22sec.
(7)If improperoperation isindicated,the controlunit isprobably defectiveandshould bechecked.
TEST PROCEDURES
PROCEDURE
LETTER COMPONENT TEST
1. Disconnectthepowersupplycord andthen removeouter case.
2. Open the door and block it open.
3. Dischargehighvoltagecapacitor.
4. Disconnectthe leadsto the primaryof thepower transformer.
5. Ensurethattheseleadsremainisolatedfromothercomponentsandovenchassisbyusinginsulation
tape.
6. Afterthat procedure,re-connect thepower supplycord.
7.RemovetheoutercaseandcheckvoltagebetweenthenormalopenterminaloftherelayRY1andthe
normal open terminal of the relay RY2 on the control unit with an A.C. voltmeter.The meter should
indicate 120 volts, if not check oven circuit.
RY1 and RY2 Relay Test
Theserelaysare operated byD.C.voltage
Check voltage at the relay coil with a D.C. voltmeter during the microwave 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 OPERATIONAL VOLTAGE CONNECTED COMPONENTS
RY1 Approx. 12.0V D.C. Oven lamp / Turntable motor / Cooling fan motor
RY2 Approx. 11.0V D.C. Power transformer
8. Disconnect the power supply cord, and then remove outer case.
9. Open the door and block it open.
10. Discharge high voltage capacitor.
11. Reconnect all leads removed from components during testing.
12. Re-install the outer case (cabinet).
13. Reconnect the power supply cord after the outer case is installed.
14. Run the oven and check all functions.
LCOMPU DEFROST TEST
KRELAY TEST

8
R-508FS
6
45
123
6
45
1
2
3
A
B
C D E F
G H
A
B
C D E F
G H
Figure S-3. CPU Unit Circuit
8
POPCORN
DE F R OS T
START
POWER
LEVE L
MINUTE
PLUS
TIMER
CLOCK
1
4
7
5
2
8
0
9
3
6
COOK
REHEAT
7 6 5
45
40
42
44
46
47
48
49
43
54
4 3 2 1
91011121314
39
COM0 COM1 COM2 COM3
AVS S
VRE F
VCC
SEG0 SEG1 SEG2 SEG3 SEG4
SEG8
P06
P07
VL2
1
5
10
15
20 45
50
55
60
24
64
25 40
80 65
70 75
30 35
41
VL1
AN7
AN6
AN5
AN4
P63
AN2
AN1
AN0
P57
P56
P55
IC1
CNTR0
P53
P52
P51
P50
P47
P46
P45
P44
P43
INT0
P10
P11
P12
P13
P14
P15
P16
P17
SEG9
SEG10
SEG11
SEG12
SEG13
SEG14
SEG15
SEG16
SEG17
SEG18
SEG19
SEG20
SEG21
SEG5 SEG6 SEG7
VL3
P41 P71 P70
XIN
XOUT
VSS
P27 P26 P25 P24 P23 P22 P21 P20 P40
RESET
SEG1 SEG2 SEG3 SEG4 SEG5 SEG6 SEG7 SEG8 SEG9
SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22
COM3 COM2
C0M1
38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15
STOP
CLEAR
53
52
51
50
41
PRESET
LED
GND
VC
INT
AN7
AN6
AN5
AN4
B UZZE R
VR
MIC R O
D20
OVEN LAMP
FAN MOTOR
TURNTABLE
MOTOR
DOOR
SENSING
SWITCH
NOTE
: IF NOT SPCIFIE D, 1/16W ± 5%
C4 0.1µ/50v
C11 0.01µ/25v C5 0.01µ/25v
C6 0.01µ/25v
R2 82
R3 4.7k
R6 1k
R 7 15k
R8 4.7kR9 4.7kR 10 4. 7k
R11 15k
R80 1M
R30 3.3k
R 40 4. 7k
R66 15k R65 15k R64 15k R63 15k R62 15k R61 15k R60 15k R67 15k
R 78 270k R 77 270k R 76 270k R 75 270k R 74 270k
C65 330p/50v C64 330p/50v C63 330p/50v C62 330p/50v C61 330p/50v C60 330p/50v
R 79 270k
C10 0.1µ/50v
C40 0.01µ /25 v
C20
0.1µ/50v
Q1
2S A1037AK
Q2
2S A1037AK
Q10
DTA143E K A
Q30
DTA143E K A
Q20
DTA143E K A
Q22
DTA123JKA
CF1
FCR4.0MC5M3
R4 4.7k
R41 15k
R68 15k
R90 15k
R69 15k
R70 15k
R71 15k
R72 15k
R73 15k
GND
LIQUID CRYSTAL DISPLAY
COOK
KGOZ.
CUPS
LBS .
NO.
DE F R OS T S E NS OR AUT O %
LS I UNIT
KEY UNIT