Sharp r-8580 manual Sensor Dummy Resistor Circuit, Steps Occurance Cause or Correction

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R-8580

TEST PROCEDURES (CONT’D)

PROCEDURE
LETTER	COMPONENT	TEST

CHECKING CONTROL UNIT

(1)Disconnect oven from power supply and remove outer case.

(2)Discharge the high voltage capacitor.

(3)Disconnect the wire leads from the cook relay.

(4)Disconnect the sensor connector that is mounted to lower position of control panel.

(5)Then connect the dummy resistor circuit (see fig.) to the sensor connector of control panel.

(6)Reconnect the oven to the power supply and check the sensor cook operation proceed as follows:

6-1. Touch SENSOR COOK pad and number 0 pad.

6-2. The control panel is in the sensor cooking operation.

6-3. After approximately 20 seconds, push plunger of select switch. This condition is same as judgement by AH sensor.

6-4. After approximately 3 seconds, cooking operation turns off, an audible signal will sound, and the display will then revert to the time of day.

If the above is not the case, the control unit is probably defective. If the above is proper, the AH sensor is probably defective.

				To	Connector	(F)
				on	Control	Untt
						CONNECTOR
Rl, R2	: loon	t	1%	1/2w	F-l -
Rl, R2	: loon	t	1%	1/2w
R3	: 10kR	? 5%		1/4W	F-2..--
R4	: 12kR	*	5%	1/4W	F-3 rc-

R4

R2iNO.

Plunger

0-J

NC

NO

I Switch

-2

Sensor Dummy Resistor Circuit

RPROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING

BOARD(PWB) IS OPEN.

To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on the PWB, and this fine pattern service as a substitute coil. If the foil pattern is open,

follow the troubleshooting guide given below for repair.

_.--

Problem: POWER CJN, indicator does not light up.

STEPS

OCCURANCE

CAUSE OR CORRECTION

1The rated voltage is not applied to POWER terminal Check supply voltage and oven main unit. of CPU connector (CN-A)

2 The rated voltage is applied to primarv side of Dower Power transformer or secondarv circuit defective.

NOTE:* At the time of these repairs, make visual in- spection of the varistor for burning damage and examine the transformer with tester for the presence of layer short-circuit (check primary coil resistance).

If any abnormalcondition is detected, replace the defective parts.

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Contents Sharp Convection Microwave Oven Microwave RadiationSharpcorporatkn OSAKA, Japan 8580Specification Product DescriptionAuto-TouchTM Control Panel OFF Condition OperationDescription of Operating Sequence Cooking ConditionPreheating Condition Convection Cooking ConditionAutomatic MIX Cooking Condition Convection Cooking ConditionEasy Defrost Cooking Sensor Cooking ConditionCompu Cook Cooking SequenceFigure O-l. Oven Schematic-OFF Condition 240V-50Hz G-4Figure O-3. Oven Schematic-Convection Cooking Condition Description and Function of Components Convection Cooking System Convection HeaterDamper OPEN-CLOSE Mechanism Servicing Problem Possible Cause Test Procedure CorrectionOFF Condjtion Problem Possible Cause Test Procedure or Correction Nents Defective Convection Heater Procedure RelayRY4 Unit Test Procedures Letter Component Magnetron Assembly Test Microwave Output PowerSwitch Test Procedure Letter Test Procedures CONT’D Component TestPower Transformer Test High Voltage Rectifier and Rectifier TestTEMP. Fuse Test Test Procedures CONT’D Letter Component Monitor Switch TestBlown Fuse Thermal CUT-OUTThermistor Test Procedure LetterDamper Switch Test Damper Motor TestTest Procedures CONT’O Letter Component Relay Unit Relay Symbol Operational Connected Components VoltageKEY Unit Test Checking the initial sensor cooking condition Testing Method for AH Sensor AND/OR Control UnitWater load cooking test Sensor Dummy Resistor Circuit Steps Occurance Cause or CorrectionOutline of Touch Control Panel Touch Control Panel AssemblyLSI Description of LSJ LSI IZA096DRKev strobe siqnal Seqment Data signalSeqment Data Siqnal Internal clock oscillation frequency input settinqPower source voltage Signal to SoundSignal svnchronized with commercial source frequencv50Hz Magnetron High-voltaae Circuit driving SignalSignal cominq from touch kev Damper motor relav driving signalInput signal which communicates the door open/close Signal coming from touch keyRI4 Temperature measurement input Oven ThermistorSensor Inuut Terminal For Manufacture TestAbsolute Humidity Sensor CircuitShapes of Electronic Components Other PrecautionsServicing Servicing of Touch Control PanelHigh Voltage Capacitor Removal Component Replacement and Adjustment ProcedurePower Transformer Removal Turntable Motor AND/OR Coupling RemovalConvection Motor Removal Magnetron RemovalCooling FAN Motor Removal Damper Upper Latch Switch / Monitor Switch RemovalLower Latch Switch and Stop Switch Removal RemovalControl Panel Assembly and CPU Unit Removal CPU Unit and KEY UnitDoor Replacement Door Replacement and AdjustmentDoor Adjustment Microwave Measurement Preparation for TestingRequirement 11II II II II OIL 8580 Figure S-3. Printed Wiring Board II IParts List AY AK AF AHQ8L RR-DZ561PDREOAT AH FOVN-A090WRYO AG AD 11 AA 13 AA Ii AA Replacement Parts List 8580 Control Panel Parts Door Assembly Miscellaneous ‘Y \‘\Packing and Accessories 8580 8580 Sharp