Sharp R-21JCA-F service manual Component Replacement and Adjustment Procedure, Outer Case Removal

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R-21JCA-F

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE

WARNING AGAINST HIGH VOLTAGE:

Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may result in severe, possibly fatal, electric shock.

(Example)

High Voltage Capacitor, Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc..

WARNING: Avoid possible exposure to microwave energy. Please follow the instructions below before operating the oven.

1.Disconnect the power supply cord.

2.Visually check the door and cavity face plate for damage (dents, cracks, signs of arcing etc.).

Carry out any remedial work that is necessary before operat- ing the oven.

Do not operate the oven if any of the following conditions exist;

1.Door does not close firmly.

2.Door hinge, support or latch hook is damaged.

3.The door gasket or seal is damaged.

4.The door is bent or warped.

5.There are defective parts in the door interlock system.

6.There are defective parts in the microwave generating and transmission assembly.

7.There is visible damage to the oven.

Do not operate the oven:

1.Without the RF gasket (Magnetron).

2.If the wave guide or oven cavity are not intact.

3.If the door is not closed.

4.If the outer case (cabinet) is not fitted.

WARNING FOR WIRING

To prevent an electric shock, take the following precau- tions.

1.Before wiring,

1)Disconnect the power supply cord.

2)Open the door and block it open.

3)Discharge the high voltage capacitor and wait for 60 seconds.

2.Don’t let the wire leads touch to the followiong parts;

1)High voltage parts:

Magnetron, High voltage transformer, High voltage capacitor and High voltage rectifier assembly.

2)Hot parts:

Oven lamp, Magnetron, High voltage transformer, and Oven cavity.

3)Sharp edge:

Bottom plate, Oven cavity, Waveguide flange, Chassis support and other metallic plate.

4)Movable parts (to prevent a fault)

Fan blade, Fan motor, Switch, Switch lever and antenna motor.

3.Do not catch the wire leads in the outer case cabinet.

4.Insert the positive lock connector until its pin is locked and make sure that the wire leads do not come off even if the wire leads are pulled.

5.To prevent an error function, connect the wire leads correctly, referring to the Pictorial Diagram.

Please refer to ‘OVEN PARTS, CABINET PARTS, CONTROL PANEL PARTS, DOOR PARTS’, when carrying out any of the following removal procedures:

OUTER CASE REMOVAL

To remove the outer case, proceed as follows.

1.Disconnect the power supply cord.

2.Open the oven door and block it open.

3.Remove the five (5) screws from rear and along the side edge of case.

4.Slide the entire case back about 3cm 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.

CAUTION: 1. DISCONNECT OVEN FROM POWER SUP PLY BEFORE REMOVING OUTER CASE.

2.DISCHARGE THE HIGH VOLTAGE CAPACI- TOR BEFORE TOUCHING ANY OVEN COM- PONENTS OR WIRING.

POWER TRANSFORMER REMOVAL

1.Disconnect the power supply cord and then remove outer case.

2.Open the oven door and block it open.

3.Discharge high voltage capacitor.

4.Disconnect the filament leads of power transformer from high voltage capacitor and the magnetron.

5.Disconnect the H.V. wire from the power transformer.

6.Disconnect the main wire harness from the power transformer.

7.Remove the two (2) screws and two (2) VCP caps holding the transformer to base plate.

8.Remove the transformer.

9.Now the power transformer is free.

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Contents Model R-21JCA-F Before Servicing When the testing is completed Dont Touch Before ServicingRequirements Microwave Measurement ProcedureLeakage test Light Duty Commercial Microwave Oven 21JCA-F Foreword Sharp Electronics CorporationMaximum width, depth and height SpecificationGeneral Information Actual capacity for holding food is lessOven Diagram 10 6OFF Condition OperationDescription of Operating Sequence Cooking ConditionFigure O-1 Oven Schematic-OFF Condition FM AMDescription and Function of Components Test Procedure Possible Case Defective Parts Troubleshooting GuideProblem Microwave Output Power Power Transformer TestThermal CUT-OUT Test 125˚C Oven High Voltage Capacitor TestThermal CUT-OUT Test 145˚C Magnetron Primary Interlock System Test Door Sensing SwitchMonitor Switch Test Primary Interlock Relay RY1Before testing Control Panel Assembly TestNoise Filter Test Test Procedures Letter Component Test Relay TestSteps Occurrence Cause or Correction Touch Control Panel Assembly Description of LSIInternal clock oscillation frequency input setting Pin No Signal Description Auto clear terminalPower source voltage Power source voltage +5VServicing of Touch Control Panel Other PrecautionsTouch Control Panel Servicing Servicing ToolsEmploying lead-free solder Precautions for Using LEAD-FREE SolderUsing lead-free wire solder SolderingPower Transformer Removal Component Replacement and Adjustment ProcedureOuter Case Removal Magnetron Removal Control Panel Assembly RemovalOven Lamp and Lamp Socket Removal Cooling FAN Motor Removal Positive Lock Connector NO-CASE Type RemovalAntenna Motor Removal Rear ViewRe-install Power Supply Cord ReplacementRemoval Door Parts Removal After any service, make sure of the following Antenna Motor Shaft ReplacementRemoval Installation of Ceramic Shelf Figure C-10. Stirrer Antenna Assembly InstallationPictorialDiagram HighvoltagecomponentsCN-A3 Pin5mm Pitch Figure S-3. Printed Wiring Board Cabinet Parts Parts ListElectric Parts Control Panel PartsMiscellaneous HOW to Order Replacement PartsDoor Parts SCREWS,NUTS and WashersOven and Cabinet Parts Control Panel Parts Packing and Accessories Copyright 2005 by Sharp Corporation ALL Rights Reserved