Sharp MMD24S, MMD24B manual Danger, Bridge Gate Dr Diamond Bar, CA, Service Manual

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SERVICE MANUAL

SERVICE MANUAL

MICROWAVE DRAWER

MMD24S / MMD24B

FOREWORD

This Manual has been prepared to provide Dacor Service Personnel with Operation and Service Information for the DACOR MICROWAVE DRAWER.

It is recommended that service personnel carefully study the entire text of this manual so that they will be qualified to render satisfactory customer service.

Check the interlock switches and the door seal carefully. Special attention should be given to avoid electrical shock and microwave radiation hazard.

WARNING

Never operate the oven until the following points are ensured.

(A)The door is tightly closed.

(B)The door brackets and hinges are not defective.

(C)The door packing is not damaged.

(D)The door is not deformed or warped.

(E)There is no other visible damage with the oven.

Servicing and repair work must be carried out only by trained service personnel.

DANGER

Certain initial parts are intentionally not grounded and present a risk of electrical shock only during servicing. Service personnel - Do not contact the following parts while the ap- pliance is energized;

Inverter unit that includes High Voltage Capacitor, High Volt- age PowerTransformer, HighVoltage Rectifier, Heat sink, etc., and Magnetron, High Voltage Harness etc.;

If provided, Vent Hood, Fan assembly, Cooling Fan Motor.

All the parts marked “*” on parts list are used at voltages more than 250V.

Removal of the outer wrapper gives access to voltage above 250V.

All the parts marked “” on parts list may cause undue microwave exposure, by themselves, or when they are damaged, loosened or removed.

1440 Bridge Gate Dr.

Diamond Bar, CA 91765

MMD24S

MMD24B

PRODUCT DESCRIPTION

SCHEMATICS

TEST PROCEDURE

TOUCH CONTROL PANEL

MICROWAVE DRAWER

DISSASSEMBLY AND ADJUSTMENT PROCEDURE

WIRING DIAGRAM

PARTS LIST

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Contents WARNING TO SERVICE PERSONNEL TABLE OF CONTENTSWARNING TO SERVICE PERSONNEL MICROWAVE MEASUREMENT PROCEDUREBEFORE SERVICING After repairing WARNING TO SERVICE PERSONNELBefore Servicing When the testing is completedB. Preparation for testing MICROWAVE MEASUREMENT PROCEDUREA. Requirements C. Leakage test1440 Bridge Gate Dr Diamond Bar, CA DANGERSERVICE MANUAL If provided, Vent Hood, Fan assembly, Cooling Fan MotorDESCRIPTION MICROWAVE DRAWER SPECIFICATIONGROUNDING INSTRUCTIONS GENERAL INFORMATIONOPERATION POWER LEVEL P-0 TO P-90 COOKINGDESCRIPTION OF OPERATING SEQUENCE OFF CONDITIONMICROWAVE SENSOR COOKING CONDITIONCooking Sequence DOOR SCHEMATIC OFF CONDITIONCLOSED, COOK OFF CONDITTION PROCEDURE TEST PROCEDURESA TOUCH CONTROL PANEL ASSEMBLY TEST Before testingC RELAY TEST COMPONENT TESTB KEY UNIT TEST DEFROST TEST Check supply voltage and oven power cordSTEPS The rated AC voltage is not present betweenWater load cooking test TESTING METHOD FOR AH SENSOR AND/OR CONTROL UNITF AH SENSOR TEST Checking the initial sensor cooking condition R1, R2 22Ω ± 1% 1/2W R3 4.3kΩ ± 5% 1/4W R4 1MΩ ± 5% 1/4W CHECKING CONTROL UNITG MAGNETRON ASSEMBLY TEST Refer to the disassembly instructions found on PageMICROWAVE OUTPUT POWER H THERMAL CUT-OUT TESTK MONITOR SWITCH TEST I SECONDARY INTERLOCK SWITCH TESTJ STOP SWITCH TEST L BLOWN MONITOR FUSE TEST M POWER TRANSFORMER TESTControl Unit and Power Unit TOUCH CONTROL PANEL ASSEMBLY4 Reset Circuit 5 Indicator CircuitPower source voltage 0V GND DESCRIPTION OF LSI IC-1Internal clock oscillation frequency setting input Power source voltage +5VSegment data signal SignalSignal coming from touch key Signal similar to P23Common relay driving signal. Square Waveform 60Hz Magnetron high-voltage circuit driving signalSignal to sound buzzer Signal to synchronize LSI with commercial power source frequencyventilation opening for sensing HUMIDITY SENSOR CIRCUIT1 Structure of Humidity Sensor 2 Operational Principle of Humidity Sensor1 Servicing the touch control panel with power supply of the oven TOUCH CONTROL PANEL SERVICING4. Other Precautions 2. Servicing of Touch Control Panel2. Using lead-free wire solder PRECAUTIONS FOR USING LEAD-FREE SOLDER1. Employing lead-free solder 3. SolderingWARNING FOR WIRING COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDUREWARNING AGAINST HIGH VOLTAGE To prevent an electric shock, take the following pre- cautionsMICROWAVE DRAWER DISASSEMBLY Un-hook/Attach Black AC Wire to Top Terminal POWER CORD REPLACEMENTUn-hook/Attach White AC Wire to Bottom Terminal Un-hook/Attach Ground to metal Tab on Back PlateSTOP SWITCH, SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH ADJUSTMENT STOP SWITCH, SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH REMOVALRe-install After adjustment, check the followingDRAWER SUPPORT ANGLE REMOVAL DRAWER ASSEMBLY AND CHOKE REMOVALDRAWER/SLIDE RAIL REMOVAL 1. Follow the Microwave Drawer disassembly as previouslySWITCH ANGLE REMOVAL SWITCH ANGLE REMOVAL/ADJUSTMENTACTUATOR REMOVAL/ADJUSTMENT Actuator adjustmentBottom cover AUTO DRAWER GEAR REMOVAL/INSTALLATIONRACK GEAR REMOVAL Installationto Back Plate HIGH VOLTAGE COMPONENTSMICRO Figure S-2. Power Unit CircuitFM A CN-ACONTROL UNITUNIT F G HA B C D E F G H Figure S-4. Printed Wiring Board of Power Unit2.5A UnitControlof 5.PrintedWiringBoardCOPYRIGHT 2008 BY DACOR, INC ALL RIGHTS RESERVED