Sharp R-4A56 Service Manual Download Page 29

Page: 29 / 40

R-4A56

SCHEMATIC

NOTE: CONDITION OF OVEN
1. DOOR CLOSED
2. CLOCK APPEARS ON DISPLAY

Figure O-1. Oven Schematic-OFF Condition (for Australia)

Figure O-1. Oven Schematic-OFF Condition (for New Zealand)

POWER TRANSFORMER

MAGNETRON

H.V. RECTIFIER

ASYMMETRIC

RECTIFIER

CAPACITOR

1.13µF

AC2100V

TURNTABLE MOTOR

FAN MOTOR

OVEN LAMP

STOP

SWITCH

MONITOR SWITCH

CONTROL

UNIT

THERMAL

CUT-OUT

UPPER

LATCH

SWITCH

EARTH

BLU

BRN

240V~50Hz

TTM

N.O.

RY-1

G-Y

COM.

FUSE

M8A

TEMP.

FUSE

RY-2

LOWER

LATCH

SWITCH

MONITOR

RESISTOR

0.8/20W

LIVE

NEUTRAL

BLU/18

BRN/18

G-Y/18

EARTH

/AC250V

FUSE

M8A

NOISE SUPPRESSION COIL

0.0022µ

/250V

THERMAL CUT-OUT

LATCH SWITCH

STOP SWITCH

OVEN LAMP

FAN MOTOR

TURNTABLE MOTOR

POWER TRANSFORMER

MAGNETRON

ASYMMETRIC RECTIFIER

CAPACITOR

AC2100V

230-240V~50Hz

1.13

0.0022µ

/250V

TEMP. FUSE

COM.

RY1

RY2

CONTROL UNIT

MONITOR SWITCH

MONITOR RESISTOR 0.8/20W

H.V. RECTIFIER

TTM

N.O.

LOWER

0.068µ

UPPER

Summary of Contents for R-4A56

Page 1: ... OVEN TABLE OF CONTENTS Page CAUTION MICROWAVE RADIATION 1 WARNING 1 PRODUCT SPECIFICATIONS 2 GENERAL INFORMATION 2 APPEARANCE VIEW 3 OPERATION SEQUENCE 4 FUNCTION OF IMPORTANT COMPONENTS 5 SERVICING 6 TEST PROCEDURE 8 TOUCH CONTROL PANEL 16 COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE 20 MICROWAVE MEASUREMENT 26 WIRING DIAGRAM 27 PICTORIAL DIAGRAM 29 CONTROL PANEL CIRCUIT 31 PRINTED WIRING BOAR...

Page 2: ...R 4A56 ...

Page 3: ...sed 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 WARNING Never oper...

Page 4: ...ng fequency 2450 MHz Case Dimensions Width 550 mm Height 312 mm Depth 420 mm Cooking Cavity Dimensions Width 381 mm Height 210 mm Depth 411 mm Turntable diameter 360mm Control Complement Touch Control System Clock 1 00 12 59 Timer 0 99 minutes 99 seconds Microwave Power for Variable Cooking Repetition Rate HIGH Full power throughout the cooking time MEDIUM HIGH approx 70 of Full Power MEDIUM appro...

Page 5: ...ck time weightorquantityoffood or toselecttheAutocookmenus EASYDEFROSTPAD Presstodefrostmeatbyentering weightonly Reheat Pies Pastries 1 piece 1 2 3 4 5 POWER LEVEL EASY DEFROST LESS MORE 2 X 3 X 4 X AUTOCOOKPAD PresstoselectAutoCookmode AUTOCOOKMENUS POWERLEVELPAD Presstoselectmicrowavepower setting Ifnotpressed HIGHis automaticallyselected 2 3 or4SERVEQUANTITYPAD Tocooktwo three orfourserves pre...

Page 6: ...wing condition CONDITION DURING DOOR OPEN SWITCH CONTACT COOKING NO COOKING Upper latch switches COM NO Closed Open Lower latch switch COM NO Closed Open Monitor switch COM NC Open Closed Stop switch COM NO Closed Open The circuits to the power transformer fan motor and turntable motor are cut off when the upper latch switch lower latch switch and stop switch are made open The oven lamp remains on...

Page 7: ...ch peak reverse voltage goes beyond the each rated peak reverse voltage The process of blowing the fuse M8A 1 The high voltage rectifier is shorted by any causes when microwave cooking 2 The peak reverse voltage of D2 of the rectifier goes beyond the rated peak reverse voltage 1 7 KV in the voltage doubler circuit 3 D2 of the rectifier is shorted 4 The large electric currents flow through the high...

Page 8: ...er the outer case has been removed in this event carry out 3D checks and then disconnect the leads to the primary of the power transformer Ensure that these leads re main isolated from other components and the oven chassis Use insulation tape if necessary When the testing is completed carry out 3D checks and reconnect the leads to the primary of the power transformer REMEMBER TO CHECK 4R 1 Reconne...

Page 9: ...rly when STOP CLEAR pad is touched Oven lamp does not light at door opened Display ap pears Oven does not start when the START pad is touched Dis play appears Oven lamp does not light Dis play appears Fan motor does not operate Display appears Turntablemotorassemblydoes notoperate Displayappears Oven or any electrical parts does not stop when cooking time is 0 or STOP CLEAR pad is touched Oven see...

Page 10: ...ows P x t 4 187 V x T P W 4 187 x V x T t Our condition for water load is as follows Room temperature around 20 C PowersupplyVoltage Ratedvoltage Water load 1000 g Initial temperature 10 2 C Heating time 47 sec P 90 x T Measuring condition 1 Container The water container must be a cylindrical borosilicate glass vessel having a maximum material thickness of 3 mm and an outside diameter of approxima...

Page 11: ...ith V ml rises T C during this microwave heating period the calorie of the water is V x T The formula is as follows P 8330 x T t Our condition for water load is as follows Room temperature 23 2 C Power supply Voltage Rated voltage Water load 2000 ml Initial temperature 23 1 C Heating time 1 min 51sec P 75 x T Measuring method A The two water containers must be prepared The water container must be ...

Page 12: ...e replaced CARRY OUT 4R CHECKS C HIGH VOLTAGE RECTIFIER ASSEMBLY TEST HIGH VOLTAGE RECTIFIER TEST CARRY OUT 3D CHECKS Isolate the high voltage rectifier assembly from the HV circuit The high voltage rectifier can be tested using an ohmmeter set to its highest range Connect the ohmmeter across the terminal B C of the high voltage rectifier and note the reading obtained Reverse the meter leads and n...

Page 13: ...or shows continuity for a short time kick and then a resistance of about 10MΩ after it has been charged D A short circuited capacitor shows continuity all the time E An open capacitor constantly shows a resistance about 10 MΩ because of its internal 10MΩ resistance F When the internal wire is opened in the high voltage capacitor shows an infinite resistance G The resistance across all the terminal...

Page 14: ...d ventilation cooling fan failure or a fault condition within the magnetron or HV circuit An open circuit thermal cut out 145 C OVEN indicates that the foods in the oven may catch fire this may be due to over heating produced by improper setting of the cooking time or failure of the control panel CARRY OUT 3D CHECKS Disconnect the leads from the motor Using an ohmmeter check the resistance between...

Page 15: ...CAUTION ONLY REPLACE FUSE M8A WITH THE CORRECT VALUE REPLACEMENT The touch control panel consists of circuits including semiconductors such as LSI ICs etc Therefore unlike conventional microwave ovens proper maintenance cannot be performed with only a voltmeter and ohmmeter In this service manual the touch control panel assembly is divided into two units Control Unit and Key Unit and troubleshooti...

Page 16: ...ntrol unit or key pad is at fault L KEY UNIT TEST KEY UNIT STOP CLEAR POWER LEVEL G 12 G 11 G 10 G 9 G 8 G 7 G 6 G 5 G 4 G 3 G 2 G 1 LESS MORE 1 2 3 4 5 6 7 8 9 0 AUTO COOK AUTO START CLOCK EASY DEFROST Reheat Beverage Soup INSTANT COOK START Rice Pasta Frozen Dinner 4 X 3 X 2 X Bacon Casseroles Chicken Pieces Reheat Pie Pastries Fish Fillets M RELAY TEST 1 CARRY OUT 3D CHECKS 2 Disconnect the lea...

Page 17: ...e of layer short circuit check primary coil resistance If any abnormal condition is detected replace the defective parts CARRY OUT 4R CHECKS RY2 S1 3 1 US RED CD GRY GE BLK AS BRN D32 TAB1 COM TAB2 H V J1 17 VRS1 T1 D31 H V POWER O L F M T T M CN A RY1 5 7 3 1 a b d c STEPS OCCURANCE CAUSE OR CORRECTION 1 The rated voltage is not applied to POWER Check supply voltage and oven main unit terminal of...

Page 18: ...lament serves as cathode The Fluorescent Display has 6 digits 13 segments are used for displaying figures The touch control section consists of the following unit as shown in the touch control panel circuit 1 Key Unit 2 Control Unit The principal functions of these units and the signals com municated among them are explained below Key Unit The key unit is composed of a matrix signals generated in ...

Page 19: ...30 R32 terminal while one of G2 line keys on key matrix is touched 7 R02 OUT Segment data signal Signal similar to D11 Key strobe signal Signal applied to touch key section A pulse signal is input to R23 R30 R32 terminal while one of G3 line keys on key matrix is touched 8 R03 OUT Segment data signal Signal similar to D11 Key strobe signal Signal applied to touch key section A pulse signal is inpu...

Page 20: ...to VC 28 RESET IN Auto clear terminal Signal is input to reset the LSI to the initial state when power is supplied Temporarily set to H level the moment power is supplied at this time the LSI is set Thereafter set at L level 29 TEST IN Connected to GND 30 OSC1 IN Internal clock oscillation frequency input setting The internal clock frequency is set by inserting the ceramic filter oscillation circu...

Page 21: ...onnected to the oven B On some models the power supply cord between the touch control panel and the oven proper is long enough that they may be separated from each other For those models therefore it is possible to check and repair the controls of the touch control panel while keeping it apart from the oven proper in this case you must short both ends of the door sensing switch on PWB of the touch...

Page 22: ...ct oven from power supply 2 Open the oven door and wedge it open 3 Remove the screws from rear and along the side edge of case 4 Slide the entire case back about 1 inch 3 cm to free it from retaining clips on the cavity face plate 5 Lift the entire case from the oven 6 Discharge the H V capacitor before carrying out any further work 7 Do not operate the oven with the outer case removed N B Step 1 ...

Page 23: ...e tab holding the oven lamp socket 5 Remove the oven lamp socket 6 Pull the wire leads from the oven lamp socket by pushing the terminal hole of the oven lamp socket with the flat type small screw driver 7 Now the oven lamp socket is free Oven lamp socket Terminal Wire lead Flat type small screw driver Terminal hole Figure C 1 Oven lamp socket 5 Remove the two 2 screws holding the turntable motor ...

Page 24: ... POSITIVE LOCK CONNECTOR REMOVAL 1 Pushing the lever of positive lock connector 2 Pull down the connector from the terminal 3 Now the connector is free Note If the positive lock has a insulation sleeve first remove it If you do not so you can not push the lever of positive lock CAUTION THE POSITIVE LOCK TERMINAL CAN NOT BE DISCONNECTED BY ONLY PULLING BECAUSE ONCE YOU SERVICE PER SONAL HAVE CONNEC...

Page 25: ...e two 2 screws holding the latch hook to the oven cavity 6 Remove the latch hook 7 Push the retaining tab slightly and remove the switch UPPER LATCH SWITCH LOWER LATCH SWITCH STOP SWITCH AND MONITOR SWITCH REMOVAL Tab Lower latch switch Tab Tab Tab Stop switch Upper latch switch Monitor switch Figure C 6 Switches 5 CARRY OUT 4R CHECKS Note Step 5 above is important and it must be done after replac...

Page 26: ...pproved microwave survey meter Refer to Microwave Measurement Procedure MONITOR SWITCH UPPER LATCH SWITCH STOP SWITCH LOWER LATCH SWITCH LATCH LEVER PLUNGER SWICTH LATCH HEAD DOOR OPEN BUTTON LATCH HEAD LATCH HOOK DOOR Figure C 7 Latch Switches Adjustment DOOR REPLACEMENT AND ADJUSTMENT 1 Adjustdoorlatchheadsatapositionwheretheysmoothly catch the latch hook through the latch holes Refer to latch s...

Page 27: ...panel as shown in Figure C 9 2 Catch the other ring of the latch spring on the tab of the latch head 3 Install the latch head to the holes in the door panel Tab of the latch head Ring Latch spring Ring Tab of the door panel Door Panel Latch head 1 2 Figure C 9 Latch head removal and re install DOOR FRAME REMOVAL Remove the door assembly refer to DOOR REPLACE MENT 1 Place the door assembly on a sof...

Page 28: ...crowave ovens must be used for testing Recommended instruments are NARDA 8100 NARDA 8200 HOLADAY HI 1500 SIMPSON 380M 2 Place the oven tray into the oven cavity 3 Place the load of 275 15ml 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 suc...

Page 29: ...UPPER LATCH SWITCH B1 B2 A5 A3 EARTH BLU BRN 240V 50Hz OL FM TTM N O RY 1 G Y COM FUSE M8A A1 TEMP FUSE RY 2 LOWER LATCH SWITCH MONITOR RESISTOR 0 8 20W LIVE NEUTRAL FM BLU 18 BRN 18 G Y 18 EARTH AC250V FUSE M8A NOISE SUPPRESSION COIL N L 0 0022µ 250V THERMAL CUT OUT LATCH SWITCH LATCH SWITCH STOP SWITCH OVEN LAMP FAN MOTOR TURNTABLE MOTOR POWER TRANSFORMER MAGNETRON ASYMMETRIC RECTIFIER CAPACITOR...

Page 30: ...LE MOTOR POWER TRANSFORMER MAGNETRON ASYMMETRIC RECTIFIER CAPACITOR AC2100V µ 230 240V 50Hz OL 1 13 0 0022µ 250V TEMP FUSE A1 B2 B1 A3 A5 COM RY1 RY2 CONTROL UNIT MONITOR SWITCH MONITOR RESISTOR 0 8 20W H V RECTIFIER TTM N O 0 068µ LOWER UPPER POWER TRANSFORMER MAGNETRON H V RECTIFIER ASYMMETRIC RECTIFIER CAPACITOR 1 13µF AC2100V TURNTABLE MOTOR FAN MOTOR OVEN LAMP STOP SWITCH MONITOR SWITCH CONTR...

Page 31: ...VEN LAMP OL RED WHT RED RED WHT RED RED RED WHT RED RED MONITOR SWITCH NC COM SW3 WHT RED 5 4 3 2 1 GRN RED 2 1 BRN ORG WHT R E D G R N W H T W H T W H T RED RED CONTROL PANEL CN B RY2 COM CN A 1 3 5 NO 2 1 CN B RY2 CN A RY2 COM NO P P P P P THERMAL CUT OUT TC 145 C OVEN P P P P P P FAN MOTOR FM HIGH VOLTAGE WIRE A HIGH VOLTAGE CAPACITOR ASYMMETRIC RECTIFIER H V RECTIFIER NOTE The marked connector...

Page 32: ...AMP OL RED WHT RED RED WHT RED RED RED WHT RED RED MONITOR SWITCH NC COM SW3 WHT RED 5 4 3 2 1 GRN RED 2 1 BRN ORG WHT R E D G R N W H T W H T W H T RED RED CONTROL PANEL CN B RY2 COM CN A 1 3 5 NO 2 1 CN B RY2 CN A RY2 COM NO P P P P P THERMAL CUT OUT TC 145 C OVEN P P P P P P FAN MOTOR FM HIGH VOLTAGE WIRE A HIGH VOLTAGE CAPACITOR ASYMMETRIC RECTIFIER H V RECTIFIER NOTE The marked connector is t...

Page 33: ...2 AN3 AVSS TEST OSC1 OSC2 VCC D0 D1 D2 D3 D4 D5 D6 D7 D8 D9 GND INT1 R3 2 R3 1 R3 0 R2 3 R2 2 R2 1 R2 0 R1 3 R1 2 R1 1 R1 0 R0 3 R0 2 R0 1 R0 0 Vdisp TG1 D11 D10 R100 1M CF100 CST4 00MGW C80 330pF x 4 R80 100K x 4 R67 VC VC D41 D40 R40 100 C40 R30 15K VC Q32 DTD143ES R41 5 1K DOOR SENSING SWITCH R69 R68 R71 R70 3 3K x 4 AVCC J7 J5 J4 3 3K x 8 D67 4 G 10 G 11 G 12 G 7 R66 D66 R65 D65 R64 D64 R63 D6...

Page 34: ...0 ZD2 R41 VC C31 SP20 D20 R20 R21 CN G 1 12 1 5 10 15 21 42 35 30 25 22 B Q50 8 VP R2 ZD1 C11 B Q10 C10 VF1 R1 C8 E C1 C2 J2 J3 C3 Q30 B E C30 R31 BC 12 E BC Q33 9 R3 10 GND R40 C40 E J11 Q32 D40 J33 R33 13 VF2 TEMP DOOR SW D41 4 3 2 1 D33 J34 R34 RED BLK TAB4 TAB3 14 D2 D1 D4 15 D3 B C E Q31 J32 R32 VRS2 RY3 RY2 S2 S1 P 6 5 4 3 2 1 US BLK CD WHT GE RED AS ORG US RED CD GRY GE BLK AS BRN D32 TAB1 ...

Page 35: ... 3 1 CPWBFA498WRK0 Control unit New zealand only 1 BF 3 1A QCNCMA234DRE0 3 pin connector A 1 AC 3 1B QCNCMA275DRE0 2 pin connector B 1 AB 3 1C QCNCWA030DRE0 12 pin connector G 1 AF 3 1D RV KXA037DRE0 Fluorescent display tube 1 AU C1 RC KZA087DRE0 Capacitor 0 1µF 50V 1 AB C2 VCEAB31VW477M Capacitor 470µF 35V 1 AC C3 VCEAB31HW335M Capacitor 3 3µF 50V 1 AA C4 VCEAB31CW476M Capacitor 47µF 16V 1 AA C5 ...

Page 36: ...0WRT0 Oven cavity 1 BK 4 10 PCUSUA368WRP0 Cushion 1 AK 4 11 MLEVPA166WRF0 Latch lever 1 AE 4 12 FROLPA047WRK0 Roller stay 1 AW 4 13 NTNT A036WRE0 Turntable 1 AX 4 14 GFTA A008WRW0 Oven lamp access cover 1 AF 4 15 NCPL A015WRF0 Turntable coupling 1 AD 4 16 PSPA A084WRE0 Foot washer 1 AB 4 17 PCOVPA212WRE0 Waveguide cover 1 AF 4 18 PCUSUA157WRP0 Cushion 1 AC 4 19 PCUSUA300WRP0 Cushion 1 AH 4 20 PPAC...

Page 37: ... zinc plated steel for Australia 1 AB 7 2 XOTSD40P12RV0 Screw M4 x 12 9 AB 7 3 XOTSD40P12000 Screw M4 x 12 7 AA 7 5 XFTSD40P30000 Screw M4 x 30 zinc plated steel 1 AA 7 6 LX CZ0052WRE0 Special screw 2 AA 7 7 LX EZA036WRE0 Special screw 2 AA 7 8 XOTSE40P08000 Screw M4 x 8 4 AB 7 9 XFPSD30P06000 Screw M3 x 6 zinc plated steel 1 AA 7 10 XFPSD40P08K00 Screw M4 x 8 zinc plated steel for Australia 2 AA ...

Page 38: ... 7 2 7 2 4 18 1 9 6 9 7 10 1 16 1 13 7 7 4 10 4 6 1 17 1 18 1 4 1 3 4 5 4 2 1 10 7 22 1 12 4 31 7 23 4 30 1 7 7 12 4 23 1 8 4 1 1 14 4 28 7 8 4 13 4 12 2 3 7 2 x 2 4 19 6 6 1 5 4 7 1 1 7 9 7 8 2 5 7 3 4 9 7 5 1 6 4 3 4 14 7 12 7 14 7 11 7 6 7 12 7 12 4 29 4 29 2 2 4 8 7 10 4 24 7 10 4 25 1 2 1 11 7 12 7 3 4 26 4 27 7 2 7 2 2 5 for New Zealand 1 11 7 1 1 19 for Australia 4 4 4 16 6 15 ...

Page 39: ...37 R 4A56 6 4 5 1 2 3 6 4 5 1 2 3 A B C D E F G H A B C D E F G H CONTROL PANEL PARTS DOOR PARTS 3 2 3 2 1 3 3 3 4 3 1 3 5 6 10 5 4 5 3 5 2 5 1 5 6 5 5 5 7 21 7 21 5 7 ...

Page 40: ...240 mm 6 12 6 4 6 7 6 14 6 13 PACKING AND ACCESSORIES TRAY HOLDER SPADFA208WRE0 TURNTABLE TRAY INSTRUCTION BOOK COOK BOOK ROLLER STAY TRAY PAD SPADFA207WRE0 DOOR PROTECTOR SPADPA178WRE0 DOOR PAD SPADFA061WRE0 CABINET COVER R 4X55B SPAKHA003WRE0 TOP PAD SPADBA524WRE0 PLASTIC BAG SSAKHA032WRE0 PACKING ADD KIT CPADBA113WRK0 PACKING CASE SPAKCC388WRE0 Australia SPAKCC390WRE0 New Zealand Not replacemen...

Search results

Summary of Contents for R-4A56

Reviews:

Related manuals for R-4A56

Brands by name

Popular brands

Sharp R-4A56, Service Manual

Search results

Summary of Contents for R-4A56

Reviews:

Related manuals for R-4A56

Brands by name

Popular brands