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18

R-2S56

SERVICING

1. Precautions for Handling Electronic Components

This unit uses CMOS LSI in the integral part of the
circuits. When handling these parts, the following pre-
cautions should be strictly followed. CMOS LSI have
extremely high impedance at its input and output termi-
nals. For this reason, it is easily influenced by the
surrounding high voltage power source, static electricity
charge in clothes, etc, and sometimes it is not fully
protected by the built-in protection circuit.
In order to protect CMOS LSI.

1)  When storing and transporting, thoroughly wrap them in

aluminium foil. Also wrap all 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. Shapes of Electronic Components

3. Servicing of Touch Control Panel

We describe the procedures to permit servicing of the
touch control panel of the microwave oven and the
precautions you must take when doing so. To perform
the servicing, power to the touch control panel is avail-
able either from the power line of the oven itself or from
an external power source.

(1) Servicing the touch control panel with power supply

of the oven:
CAUTION:
THE HIGH VOLTAGE TRANSFORMER OF THE MI-
CROWAVE OVEN IS STILL LIVE DURING SERVIC-
ING PRESENTS A HAZARD.
Therefore, when checking the performance of the touch
control panel, put the outer cabinet on the oven to avoid
touching the high voltage transformer, or unplug the
primary terminal (connector) of the high voltage trans-
former to turn it off; the end of such connector must 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 between the

touch control panel and the oven itself is so short that the
two can’t be separated. For those models, check and

approx. 1M ohm

repair all the controls (sensor-related ones included) of
the touch control panel while keeping it connected to the
oven.

B.  On some models, the power supply cord between the

touch control panel and the oven proper is long enough
that they may be separated from each other. For those
models, therefore, it is possible to check and repair the
controls of the touch control panel while keeping it apart
from the oven proper; in this case you must short both
ends of the door sensing switch (on PWB) of the touch
control panel with a jumper, which brings about an
operational state that is equivalent to the oven door
being closed. As for the sensor-related controls of the
touch control panel, checking them is possible if dummy
resistor(s) with resistance equal to that of the controls
are 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 door sensing
switch (on PWB) of the touch control panel,which brings
about an operational state that is equivalent to the oven
door being closed. Connect an external power source to
the power input terminal of the touch control panel, then
it is possible to check and repair the controls of the touch
control panel it is also possible to check the sensor-
related controls of the touch control panel by using the
dummy resistor(s).

4. Servicing Tools

Tools required to service the touch control panel assem-
bly.

1) Soldering iron: 30W

 (It is recommended to use a soldering iron with a
grounding terminal.)

2) Oscilloscope: Single beam, frequency range: DC-10MHz

type or more advanced model.

3) Others: Hand tools

5. Other Precautions
1) Before turning on the power source of the control unit,

remove the aluminium foil applied for preventing static
electricity.

2)   After aluminium foil is removed, be careful that abnormal

voltage due to static electricity etc. is not applied to the
input or output terminals.

3) Attach connectors, electrolytic capacitors, etc. to PWB,

making sure that all connections are tight.

4) Be sure to use specified components where high preci-

sion is required.

E

C

B

E

C B

IC
LM7905CT

Transistor
DTB123EA

Transistor
DTA143ES
DTB143ES
DTD143ES

3

2

1

Summary of Contents for R-2S56

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 7 TEST PROCEDURE 9 TOUCH CONTROL PANEL 16 COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE 19 MICROWAVE MEASUREMENT 25 WIRING DIAGRAM 26 PICTORIAL DIAGRAM 28 CONTROL PANEL CIRCUIT 30 PRINTED WIRING BOAR...

Page 2: ...R 2S56 ...

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: ... Control Complement Touch Control System Timer 0 99 minutes 90 seconds Microwave Power for Variable Cooking Repetition Rate HIGH Full power throughout the cooking time MEDIUM HIGH approx 70 of FULL Power MEDIUM approx 50 of FULL Power MEDIUM LOW approx 30 of FULL Power LOW approx 10 of FULL Power TIME pads AUTO COOK DEFROST pad STOP CLEAR pad POWER LEVEL SERVES pad INSTANT COOK START pad AUTO COOK...

Page 5: ... not pressed 100 is automatically selected Press to enter serves after selecting AUTO COOK DEFROST menu d STOP CLEAR PAD Press to clear during programming Pressoncetostopoperationofovenduringcooking press twice to cancel cooking programme e INSTANT COOK START PAD Pressoncetocookfor1minuteat100 orincrease by 1 minute multiples each time this pad is pressed during cooking Press to start oven after s...

Page 6: ...G NOCOOKING 1st latch switches COM NO Closed Open 2nd 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 1st latch switch 2nd latch switch and stop switch are made open The oven lamp remains on even if the oven door is opened after the cooking cycle has been interr...

Page 7: ...r or high voltage rectifier are shorted when the each peak reverse voltage goes beyond the each rated peak reverse voltage The process of blowing the fuse 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 Th...

Page 8: ...in TURNTABLE MOTOR The turntable motor drives the roller stay to rotate the turntable FAN MOTOR FM The fan motor drives a blade which draws external cool air This cool air is directed through the air vanes surrounding the magnetron and cools the magnetron This air is chan nelled through the oven cavity to remove steam and va pours given off from the heating foods It is then exhausted through the e...

Page 9: ...ry out 3D checks and reconnect the leads to the primary of the power transformer REMEMBER TO CHECK 4R 1 Reconnectallleadsremovedfromcomponentsduring testing 2 Replace the outer case cabinet 3 Reconnect the supply 4 Run the oven Check all functions Microwave ovens should not be run empty To test for the presence of microwave energy within a cavity place a cup of cold water on the oven turntable clo...

Page 10: ...ate prop erly when STOP CLEAR pad is touched Oven lamp does not light at door opened Display appears Oven does not start when the START pad is touched Display appears Oven lamp does not light Display appears Fan motor does not operate Dis play appears Turntable motor assembly does not operate Display appears Oven or any electrical parts does not stop when cooking time is 0 or STOP CLEAR pad is tou...

Page 11: ...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 60 sec P 70 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 12: ...s T C during this microwave heating period the calorie of the water is V x T The formula is as follows P x t 4 2 V x T P W 4 2 x V x T t Our condition for water load is as follows Room temperature around 23 2 C Power supply Voltage Rated voltage Water load 2000 ml Initial temperature 23 1 C Heating time 2 min 20sec P 60 x T Measuring method A The two water containers must be prepared The water con...

Page 13: ...d should be 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 l...

Page 14: ...ich is set to the highest resistance range C A normal capacitor 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...

Page 15: ...cavity has overheated this may be due to no load operation An open circuit thermal cut out 95 C indicates that the fan motor winding has overheated this may be due to resisted ventilation or locked cooling fan CARRY OUT 3D CHECKS Disconnect the leads from the motor Using an ohmmeter check the resistance between the two terminals as described in the table below H MOTOR WINDING TEST If incorrect rea...

Page 16: ...problems caused by defective control unit a Buzzer does not sound or continues to sound b Cooking is not possible K TACT SWITCH TEST If the display fails to clear when the STOP CLEAR tact switch is depressed first verify that the door sensing switch stop switch operates properly that is the contacts are closed when the door is closed and open when the door is open If the door sensing switch stop s...

Page 17: ...attern is open follow the troubleshooting guide given below for repair Problem POWER ON indicator does not light up CARRY OUT 3D CHECKS N NOISE FILTER TEST CARRY OUT 3D CHECKS Disconnect the leads from the terminals of the noise filter Using an ohmmeter check between the terminals as described in the following table If incorrect readings are obtained replace the noise filter unit CARRY OUT 4R CHEC...

Page 18: ...SI through R81 R83 to perform the function that was requested 2 LSI This LSI controls the key strobe signal relay driving signal for oven function and indicator signal 3 Power Source Circuit This circuit generates voltages necessary in the control unit Symbol Voltage Application VC 5V LSI IC1 DESCRIPTION OF LSI LSI IZA582DR The I O signal of the LSI IZA582DR is detailed in the following table Pin ...

Page 19: ...touched 18 R62 OUT Segment data signal Signal similar to R50 Switch strobe signal Signal applied to tact switch section A pulse signal is input to R81 R83 terminal while one of dioide D93 line switches on switch matrix is touched 19 R63 OUT Segment data signal Signal similar to R50 20 INT2 IN Signal synchronized with commercial source frequency 50Hz This is basic timing for time processing of LSI ...

Page 20: ... panel while keeping it connected to the oven B On some models the power supply cord between the touch control panel and the oven proper is long enough that they may be separated from each other For those models therefore it is possible to check and repair the controls of the touch control panel while keeping it apart from the oven proper in this case you must short both ends of the door sensing s...

Page 21: ...NENTS REMOVAL HIGH VOLTAGE CAPACITOR AND HIGH VOLTAGE RECTIFIER ASSEMBLY 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 2 and 6 form the basis of the 3D checks To remove the components proceed as follows 1 CARRY OUT 3D CHECKS 2 Lift up the HVC cover 3 DisconnecttheH V wireoftheH V rectifierassembly from the power ...

Page 22: ...eces do not enter the gap between the rotor and the stator of the fan motor Because the rotor is easy to be shaven by pliers and metal pieces may be produced Do not touch the pliers to the coil of the fan motor because the coil may be cut or injured Donottransformthebracketbytouchingwiththe pliers 2 Remove the fan blade assembly from the shaft of the fan motor by pulling and rotating the fan blade...

Page 23: ...e lock so that the lever face you Service engineers Terminal Push Pull down 1 2 Lever Positive lock connector Figure C 2 Positive lock connector TURNTABLE MOTOR REPLACEMENT Removal 1 Disconnect the oven from the power supply 2 Remove the turntable and roller stay from the oven cavity 3 Turn the oven over 4 Cutthefour 4 bridgesholdingtheturntablemotorcover to the bottom plate L with the cutting pli...

Page 24: ...rom the fuse holder referring to the Figure C 5 a 4 Cut away the connector 5 Release the power supply cord from the rear cabinet referring to the Figure C 5 b 6 Now the power supply cord is free POWER SUPPLY CORD OVEN CAVITY BACK PLATE GREEN YELLOW WIRE BROWN WIRE OVEN CAVITY BLUE WIRE SCREW CONNECTOR FUSE HOLDER Figure C 5 a Power Supply Cord Replacement for Australia Re install 1 Insert the moul...

Page 25: ...the following adjustment should be made 1 CARRY OUT 3D CHECKS 2 Loosen the two 2 screws holding the latch hook to the oven cavity front flange 3 With door closed adjust the latch hook by moving it back and forward In and out play of the door allowed by the latch hook should be less than 0 5 mm The horizontal position of the latch hook should be placed where the monitor switch and the stop switch h...

Page 26: ... face depressed toward the cavity face plate 4 Reinstall outer case and check for microwave leakage around the door with an approved microwave survey meter Refer to Microwave Measure ment Procedure UPPER OVEN HINGE DOOR ASSEMBLY LATCH HEADS RE INSTALL RE INSTALL LOWER OVEN HINGE SCREW SCREW Figure C 9 Door Assembly Replacement and Adjustment CHOKE COVER REMOVAL 1 Insertanironplate thicknessofabout...

Page 27: ...owave 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 center 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 ...

Page 28: ...250V 0 0022µ AC250V RESISTOR 10M 0 5W THERMAL CUT OUT 95 C TEMP FUSE 150 C OVEN TEMP FUSE 150 C MG STOP SWITCH H V RECTIFIER CAPACITOR 0 94µ AC2000V A5 L N POWER TRANSFORMER MAGNETRON H V RECTIFIER ASYMMETRIC RECTIFIER CAPACITOR 0 94µ AC2000V TURNTABLE MOTOR FAN MOTOR OVEN LAMP STOP SWITCH MONITOR SWITCH CONTROL UNIT TEMP FUSE 150 C OVEN 2ND LATCH SWITCH B1 B2 A5 A3 EARTH BLU 18 BRN 18 OL FM TTM N...

Page 29: ...TEMP FUSE 150 C MG FM BLU 18 BRN 18 G Y 18 EARTH NOISE SUPPRESSION COIL 1ST LATCH SWITCH 2ND LATCH SWITCH OVEN LAMP FAN MOTOR TURNTABLE MOTOR POWER TRANSFORMER MAGNETRON ASYMMETRIC RECTIFIER OL A1 B2 B1 A3 COM RY1 RY2 CONTROL UNIT MONITOR SWITCH MONITOR RESISTOR 0 8 20W TTM N O 240V 50Hz FUSE M6 3A RESISTOR 1 5M 0 5W LINE CROSS CAPACITOR 0 068µ AC250V LINE BYPASS CAPACITOR 0 0022µ AC250V 0 0022µ A...

Page 30: ...N LAMP GRY STOP SWITCH MONITOR RESISTOR R E D R E D TEMP FUSE 150 C MG W H T G R Y ORG GRN RED 2 1 BLK BLK RED GRN GRN TOUCH CONTROL PANEL CN B RY2 COM CN A NO 2 1 T1 1 5 RY2 RY2 RED CN A CN B THERMAL CUT OUT 95 C RED GRY ORG ORG GRY RED POWER SUPPLY CORD OVEN CAVITY BACK PLATE SCREW GREEN YELLOW WIRE WHT NO COM NC COM NO COM COM NO ORG 1 2 4 BLK 5 GRY 3 R E D W H T WHT WHT COM NO GRN 3 SP40 RY2 C...

Page 31: ... OVEN LAMP GRY STOP SWITCH MONITOR RESISTOR R E D R E D TEMP FUSE 150 C MG W H T G R Y ORG GRN RED 2 1 BLK BLK RED GRN GRN TOUCH CONTROL PANEL CN B RY2 COM CN A NO 2 1 T1 1 5 RY2 RY2 RED CN A CN B THERMAL CUT OUT 95 C RED GRY ORG ORG GRY RED POWER SUPPLY CORD OVEN CAVITY BACK PLATE SCREW GREEN YELLOW WIRE BLUE WIRE BROWN WIRE NOISE FILTER WHT NO COM NC COM NO COM COM NO ORG 1 2 4 BLK 5 GRY 3 R E D...

Page 32: ...K S0 R90 R83 R82 R81 INT2 R63 R62 R61 R60 R53 XOUT XIN R70 R71 R72 R40 R41 R42 R43 R50 R51 R52 VSS 13 14 13 14 a b c d e f g h 11 10 8 6 5 12 7 9 16 15 3 2 1 18 17 4 R77 R76 R78 R75 R74 R73 R72 R71 D93 D92 D91 SWITCH UNIT MAIN UNIT 150 x 8 LED71 LED72 ANODE C SW1 10 MIN SW2 1 MIN SW3 10 SEC SW4 NOTE IF NOT SPECIFIED 1 4W 5 IF NOT SPECIFIED 1SS270A IF NOT SPECIFIED 0 01µF 16V Figure S 2 Control Pan...

Page 33: ... D93 SW1 R91 R93 R92 R2 SW2 SW3 D92 Q74 B E Q73 B E 1 14 15 28 IC1 R72 CF1 R10 C10 R73 R71 SW4 E B Q10 ZD10 C4 B E B E Q71 Q72 SW6 SW7 SW5 B E Q40 C20 C3 C50 R81 C80 R20 C1 C2 Q1 D81 RY1 R51 R50 D50 D51 B Q80 B E E Q82 SP40 R40 F1 J2 D1 D2 D3 VRS1 CN A J1 E B Q3 T1 RY2 F OL TTM FAN M POWER 1 5 ZD3 R6 J3 B E Q81 R80 C5 C6 D82 Q20 B E C81 DOOR SW 2 1 CN B ...

Page 34: ... B 1 AB C1 VCEAB31CW477M Capacitor 470uF 16V 1 AB C2 RC KZA087DRE0 Capacitor 0 1uF 50V 1 AB C3 VCEAB31CW476M Capacitor 47uF 16V 1 AA C4 VCKYD11CY103N Capacitor 0 01uF 16V 1 AH C5 6 VCEAB31VW107M Capacitor 100uF 35V 2 AB C10 VCKYD11CY103N Capacitor 0 01uF 16V 1 AH C20 VCTYF31HF103Z Capacitor 0 01uF 50V 1 AB C50 VCKYD11CY103N Capacitor 0 01uF 16V 1 AH C80 VCEAB31HW104M Capacitor 0 1uF 50V 1 AM C81 V...

Page 35: ... lever 1 AL 4 16 PCOVPA276WRE0 Waveguide cover 1 AL 4 17 PCOVPA277WRF0 HVC cover 1 AL 4 18 PCUSUA193WRP0 Cushion 1 AB 4 19 PCUSUA235WRP0 Exhaust Cushion 1 AF 4 20 PCUSUA376WRP0 Cushion 2 AG 4 21 PFILWA041WRE0 Lamp filter 1 AF 4 22 PPACGA097WRE0 O Ring 1 AG 4 23 LANG A044WRW0 Air guide 1 AL 4 24 PCUSGA208WRP0 Cushion 1 AC 4 25 PCUSGA389WRP0 Cushion 1 AG 4 26 LX WZA028WRE0 Washer 1 AB DOOR PARTS 5 D...

Page 36: ... 2 AA 7 8 LX EZA045WRE0 Special screw 5 AA 7 9 XFPSD40P08K00 Screw 4mm X 8mm 2 AA 7 10 XFPSD40P08000 Screw 4mm X 8mm 7 AA 7 11 XOTSD40P12RV0 Screw 4mm X 12mm 13 AA 7 12 XOTSE40P08000 Screw 4mm X 8mm 4 AA 7 13 XEPSD30P06000 Screw 3mm X 6mm 4 AA 7 15 XWHNZ40 10080 Washer 4mm X 1mm 1 AB 7 16 XFPSD30P10000 Screw 3mm X 10mm for Australia 1 AA HOW TO ORDER REPLACEMENT PARTS To have your order filled pro...

Page 37: ...7 8 7 10 4 3 4 19 7 12 1 8 7 5 7 5 7 11 7 10 4 16 4 1 4 22 7 9 1 18 7 3 7 5 7 6 4 4 7 4 1 7 4 5 1 15 7 3 4 17 7 5 7 5 4 13 7 2 1 5 4 8 4 12 2 2 4 9 7 11 2 4 7 5 7 8 7 11 7 5 2 4 7 11 2 3 4 11 7 11 4 2 4 18 6 4 7 8 7 5 4 10 7 11 1 16 1 14 6 5 4 6 1 11 1 17 1 12 4 26 4 15 1 1 4 25 4 24 7 15 7 7 7 1 7 10 1 13 7 9 1 20 1 6 6 8 for New Zealand 6 10 1 21 7 16 1 4 for Australia ...

Page 38: ...36 R 2S56 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 5 4 5 5 1 5 2 5 3 5 7 5 5 5 6 7 13 7 13 DOOR PARTS 3 2 3 3 3 4 3 6 3 5 x 10 3 1 3 7 6 6 3 2 1 ...

Page 39: ...ems Actual wire harness may be different than illustration 6 2 COOK BOOK TRAY PAD ASSY CPADBA172WRK0 6 3 PAD HOLDER SPAKFA012WRE0 80 5 PACKING CASE DOOR PROTECTION SHEET SPADPA204WRE0 MICROWAVE OVEN PACKING PAD KIT CPADBA165WRK0 POLYETHYLENG BAG SSAKHA014WRE0 PACKING AND ACCESSORIES SPAKCC382WRE0 Australia Model SPAKCC383WRE0 New Zealand Model 6 9 MISCELLANEOUS ...

Page 40: ...38 R 2S56 94SHARP CORP 07K0 920E Printed in Australia ...

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