Sharp r-8580 manual Test Procedures CONT’D Letter Component Monitor Switch Test, Blown Fuse

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R-8580

TEST

PROCEDURES

(CONT’D)

PROCEDURE

 

 

 

LETTER

COMPONENT

TEST

 

MONITOR

SWITCH TEST

Before performing this test, disconnect oven from power supply and make sure that the upper latch switch is operating properly referring to the above Switch Test Procedure.

Disconnect the wire lead from the monitor switch (NC) terminal. Check the monitor switch operation by using the ohmmeter as follows. When the door is open, the meter should indicate a closed circuit.

When the monitor switch actuater is pushed by a screw driver through the upper latch hole on the front plate of the oven cavity with the door opened (in this condition the plunger of the monitor switch is pushed in), the meter should indicate an open circuit.

If improper operation is indicated, replace the defective switch..

After testing the monitor switch, re-connect the wire lead to the monitor switch (NC) terminal.

SCREW.

\

UPPER ’

LACCH

HOLE

G

BLOWN FUSE

If the fuse in the upper latch-monitor switch circuit is blown when the door is opened, check the upper latch switch and monitor switch according to the Test Procedure for those switches, before replacing the blown fuse.

If the fuse is replaced, the monitor switch should be replaced at the same time.

If the fuse is blown by improper switch operation, adjust or replace the defective switch, fuse at the same time.

Replace the fuse and monitor switch, even if the switches operate normally

CAUTION; REPLACEMENT FUSE MUST BE THE LISTED FUSE IN PARTS LIST.

H

TEMP. FUSE TEST

I

.

A continuity check across the temp. fuse terminals should indicate a closed circuit.

If the temperature of the magnetron reaches 142 ‘C, the temp. fuse opens. If the temp. fuse has opened, replace the fuse. An open temp. fuse indicates overheating of the magnetron assembly. Check for restricted air flow to the magnetron through the opening in the chassis, especially the cooling duct and tolling fan.

THERMAL CUT-OUT

A continuity check across the thermal cut-out terminals should indicate a closed circuit unless the temperature of the thermal cut-out reaches approximately 140 “C. The termal cut-out resets automatically at approximately 115 “C.

If the thermal cut-out has opened under the normal condition, replace the same one is parts list. An open thermal cut-out indicates overheating of the heater unit. Check for restricted air flow to the heater unit through the vent holes of the oven cavity, especially the heater duct and con- vection fan

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Contents Sharp Sharpcorporatkn OSAKA, Japan Microwave RadiationConvection Microwave Oven 8580Product Description SpecificationAuto-TouchTM Control Panel Description of Operating Sequence OperationOFF Condition Cooking ConditionAutomatic MIX Cooking Condition Convection Cooking ConditionPreheating Condition Convection Cooking ConditionCompu Cook Sensor Cooking ConditionEasy Defrost Cooking Cooking Sequence240V-50Hz G-4 Figure O-l. Oven Schematic-OFF ConditionFigure O-3. Oven Schematic-Convection Cooking Condition Description and Function of Components Damper OPEN-CLOSE Mechanism Convection HeaterConvection Cooking System OFF Condjtion Problem Possible Cause Test Procedure CorrectionServicing Problem Possible Cause Test Procedure or Correction Nents Defective Convection Heater Procedure RelayRY4 Unit Microwave Output Power Test Procedures Letter Component Magnetron Assembly TestPower Transformer Test Procedure Letter Test Procedures CONT’D Component TestSwitch Test High Voltage Rectifier and Rectifier TestBlown Fuse Test Procedures CONT’D Letter Component Monitor Switch TestTEMP. Fuse Test Thermal CUT-OUTDamper Switch Test Procedure LetterThermistor Test Damper Motor TestRelay Symbol Operational Connected Components Voltage Test Procedures CONT’O Letter Component Relay UnitKEY Unit Test Water load cooking test Testing Method for AH Sensor AND/OR Control UnitChecking the initial sensor cooking condition Steps Occurance Cause or Correction Sensor Dummy Resistor CircuitLSI Touch Control Panel AssemblyOutline of Touch Control Panel LSI IZA096DR Description of LSJSeqment Data Siqnal Seqment Data signalKev strobe siqnal Internal clock oscillation frequency input settinqSignal svnchronized with commercial source frequencv50Hz Signal to SoundPower source voltage Magnetron High-voltaae Circuit driving SignalInput signal which communicates the door open/close Damper motor relav driving signalSignal cominq from touch kev Signal coming from touch keySensor Inuut Temperature measurement input Oven ThermistorRI4 Terminal For Manufacture TestSensor Circuit Absolute HumidityServicing Other PrecautionsShapes of Electronic Components Servicing of Touch Control PanelPower Transformer Removal Component Replacement and Adjustment ProcedureHigh Voltage Capacitor Removal Turntable Motor AND/OR Coupling RemovalCooling FAN Motor Removal Magnetron RemovalConvection Motor Removal Lower Latch Switch and Stop Switch Removal Upper Latch Switch / Monitor Switch RemovalDamper RemovalCPU Unit and KEY Unit Control Panel Assembly and CPU Unit RemovalDoor Adjustment Door Replacement and AdjustmentDoor Replacement Requirement Preparation for TestingMicrowave Measurement 11II II II II OIL 8580 II I Figure S-3. Printed Wiring BoardAY AK AF AH Parts ListRR-DZ561PDREO Q8LAT AH FOVN-A090WRYO AG AD 11 AA 13 AA Ii AA Replacement Parts List 8580 ‘Y \‘\ Control Panel Parts Door Assembly MiscellaneousPacking and Accessories 8580 8580 Sharp
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