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19

R-4A56

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

from the oven proper:
CAUTION:
THE HIGH VOLTAGE TRANSFORMER OF THE MI-
CROWAVE OVEN IS STILL ALIVE TO GIVE YOU
DANGER  DURING SERVICING:
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

E

C B

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)  Connect the connector of the key unit to the control unit

being sure that the lead wires are not twisted.

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

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

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

making sure that all connections are tight.

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

sion is required.

Transistor
DTA114ES
DTA143ES
DTC143ES
DTD143ES

Содержание R-4A56

Страница 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...

Страница 2: ...R 4A56 ...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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 ...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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 ...

Страница 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...

Страница 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...

Страница 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...

Страница 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 ...

Страница 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 ...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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...

Страница 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 ...

Страница 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 ...

Страница 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...

Страница 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 ...

Страница 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 ...

Страница 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 ...

Страница 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...

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