Sharp MMD24B, MMD24S manual Test Procedures, Component Test, Letter, Water load cooking test

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FAH SENSOR TEST

MMD24S

MMD24B

TEST PROCEDURES

PROCEDURE

COMPONENT TEST

LETTER

 

11)Discharge high voltage capacitor.

12)Reconnect all leads removed from components during testing.

13)Re-install the outer case (cabinet).

14)Reconnect the power supply cord after the outer case is installed.

15)Run the oven and check all functions.

FAH SENSOR TEST

Checking the initial sensor cooking condition

WARNING : The oven should be fully assembled before following procedure.

(1)The oven should be plugged in at least two minutes before sensor cooking.

(2)Room temperature should not exceed 95οF (35οC).

(3)The unit should not be installed in any area where heat and steam are generated. The unit should not be installed, for example, next to a conventional surface unit. Refer to the “INSTALLATION INSTRUCTIONS” of the operation manual.

(4)Exhaust vents are provided on the back of the unit for proper cooling and air flow in the cavity. To permit adequate ventilation, be sure to install so as not to block these vents. There should be some space for air circulation.

(5)Be sure the exterior of the cooking container and the interior of the oven are dry. Wipe off any moisture with a dry cloth or paper towel.

(6)The Sensor works with food at normal storage temperature. For example, chicken pieces would be at refrigerator temperature and canned soup at room temperature.

(7)Avoid using aerosol sprays or cleaning solvents near the oven while using Sensor settings. The sensor will detect the vapor given of by the spray and turn off before food is properly cooked.

(8)If the sensor has not detected the vapor of the food, ERROR will appear and the oven will shut off.

Water load cooking test

WARNING : The oven should be fully assembled before following procedure.

Make sure the oven has been plugged in at least two minutes before checking sensor cook operation. The cabinet should be installed and screws tightened.

(1)Fill approximately 200 milliliters (7.2 oz) of tap water in a 1000 milliliter measuring cup.

(2)Place the container on the center of tray in the oven cavity.

(3)Close the drawer.

(4)Touch the TIMER/CLOCK pad once, the POWER LEVEL pad twice and the START pad once. And touch the number pads 1 once and the number pad 4 once. Now, the oven is in the sensor cooking condition, and "AH20" and "ON" will appear in the display.

(5)The oven will operate for the first 16 seconds, without generating microwave energy.

NOTE: ERROR will appear if the door is opened or STOP/CLEAR pad is touched during first stage of sensor cooking.

(6) After approximately 16 seconds, microwave energy is produced.

If ERROR is displayed or the oven does not turn off, replace the AH sensor or check the control unit, refer to explanation below. If the oven stops after 5 minutes and no ERROR code is displayed, then the AH sensor is normal. Check other parts except the AH sensor.

TESTING METHOD FOR AH SENSOR AND/OR CONTROL UNIT

To determine if the sensor is defective, the simplest method is to replace it with a new replacement

sensor.

(1)Disconnect the power supply cord, and then disassemble as per "MICROWAVE DRAWER DISASSEMBLY" page 27.

(2)Open the drawer and block it open.

(3)Discharge high voltage capacitor.

(4)Remove the AH sensor.

(5)Install the new AH sensor.

(6)Reconnect all leads removed from components during testing.

(7)Re-install the covers.

(8)Reconnect the power supply cord after the covers are installed.

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

9-1. Fill approximately 200 milliliters (7.2 oz) of tap water in a 1000 milliliter measuring cup.

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Contents WARNING TO SERVICE PERSONNEL TABLE OF CONTENTSWARNING TO SERVICE PERSONNEL MICROWAVE MEASUREMENT PROCEDUREBEFORE SERVICING Before Servicing WARNING TO SERVICE PERSONNELAfter repairing When the testing is completedA. Requirements MICROWAVE MEASUREMENT PROCEDUREB. Preparation for testing C. Leakage testSERVICE MANUAL DANGER1440 Bridge Gate Dr Diamond Bar, CA If provided, Vent Hood, Fan assembly, Cooling Fan MotorMICROWAVE DRAWER SPECIFICATION DESCRIPTIONGENERAL INFORMATION GROUNDING INSTRUCTIONSDESCRIPTION OF OPERATING SEQUENCE POWER LEVEL P-0 TO P-90 COOKINGOPERATION OFF CONDITIONMICROWAVE SENSOR COOKING CONDITIONCooking Sequence DOOR SCHEMATIC OFF CONDITIONCLOSED, COOK OFF CONDITTION A TOUCH CONTROL PANEL ASSEMBLY TEST TEST PROCEDURESPROCEDURE Before testingC RELAY TEST COMPONENT TESTB KEY UNIT TEST STEPS Check supply voltage and oven power cordDEFROST TEST 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 CHECKING CONTROL UNIT R1, R2 22Ω ± 1% 1/2W R3 4.3kΩ ± 5% 1/4W R4 1MΩ ± 5% 1/4WMICROWAVE OUTPUT POWER Refer to the disassembly instructions found on PageG MAGNETRON ASSEMBLY TEST H THERMAL CUT-OUT TESTK MONITOR SWITCH TEST I SECONDARY INTERLOCK SWITCH TESTJ STOP SWITCH TEST M POWER TRANSFORMER TEST L BLOWN MONITOR FUSE TEST4 Reset Circuit TOUCH CONTROL PANEL ASSEMBLYControl Unit and Power Unit 5 Indicator CircuitInternal clock oscillation frequency setting input DESCRIPTION OF LSI IC-1Power source voltage 0V GND Power source voltage +5VSignal coming from touch key SignalSegment data signal Signal similar to P23Signal to sound buzzer Magnetron high-voltage circuit driving signalCommon relay driving signal. Square Waveform 60Hz Signal to synchronize LSI with commercial power source frequency1 Structure of Humidity Sensor HUMIDITY SENSOR CIRCUITventilation opening for sensing 2 Operational Principle of Humidity Sensor4. Other Precautions TOUCH CONTROL PANEL SERVICING1 Servicing the touch control panel with power supply of the oven 2. Servicing of Touch Control Panel1. Employing lead-free solder PRECAUTIONS FOR USING LEAD-FREE SOLDER2. Using lead-free wire solder 3. SolderingWARNING AGAINST HIGH VOLTAGE COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDUREWARNING FOR WIRING To prevent an electric shock, take the following pre- cautionsMICROWAVE DRAWER DISASSEMBLY Un-hook/Attach White AC Wire to Bottom Terminal POWER CORD REPLACEMENTUn-hook/Attach Black AC Wire to Top Terminal Un-hook/Attach Ground to metal Tab on Back PlateRe-install STOP SWITCH, SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH REMOVALSTOP SWITCH, SECONDARY INTERLOCK SWITCH AND MONITOR SWITCH ADJUSTMENT After adjustment, check the followingDRAWER/SLIDE RAIL REMOVAL DRAWER ASSEMBLY AND CHOKE REMOVALDRAWER SUPPORT ANGLE REMOVAL 1. Follow the Microwave Drawer disassembly as previouslyACTUATOR REMOVAL/ADJUSTMENT SWITCH ANGLE REMOVAL/ADJUSTMENTSWITCH ANGLE REMOVAL Actuator adjustmentRACK GEAR REMOVAL AUTO DRAWER GEAR REMOVAL/INSTALLATIONBottom cover InstallationHIGH VOLTAGE COMPONENTS to Back PlateFM A Figure S-2. Power Unit CircuitMICRO CN-AUNIT UNITCONTROL F G HA B C D E F G H Figure S-4. Printed Wiring Board of Power Unit2.5A 5.PrintedWiringBoard UnitControlofCOPYRIGHT 2008 BY DACOR, INC ALL RIGHTS RESERVED