Sharp R-520LW Checking Control Unit, R1, R2 22Ω ± 1% 1/2W R3 4.3Ω ± 5% 1/4W R4 1MΩ ± 5% 1/4W

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R - 5 2 0 L K

R-520LW

If new sensor dose not operate properly, the problem is with the control unit, and refer to explanation below.

CHECKING CONTROL UNIT

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

(2)Open the door and block it open.

(3)Discharge high voltage capacitor.

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

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

(6)Disconnect the leads to the primary of the power transformer.

(7)Ensure that these leads remain isolated from other components and oven chassis by using insulation tape.

(8)After that procedure, re-connect the power supply cord.

(9)Check the sensor cook operation proceed as follows:

9-1. Open the door. Touch the TIMER/CLOCK pad once and the POWER LEVEL pad twice. Close the door and touch the START pad once. Open the door and touch the number pads 1 once and the number pad 4. Close the door and the touch the START pad.

9-2. The control panel is in the sensor cooking operation.

9-3. After approximately 25 seconds, push plunger of select switch for more than 3 seconds. This condition is same as judgement by AH sensor.

9-4. After approximately 3 seconds, the display shows “ X X . X X “ which is the time for detecting moisture. If the above is not the case, the control unit is probably defective.

If the above is proper, the AH sensor is probably defective.

(10)Disconnect the power supply cord, and then remove outer case.

(11)Open the door and block it open.

(12)Discharge high voltage capacitor.

(13)Disconnect the dummy resistor circuit from the sensor connector of control panel.

(14)Carry out necessary repair.

(15)Reconnect all leads removed from components during testing and repairing.

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

(17)Reconnect the power supply cord after the outer case is installed. Run the oven and check all functions.

(18)Carry out "Water load cooking test" again and ensure that the oven works properly.

R1, R2 : 22Ω ± 1% 1/2W R3 : 4.3Ω ± 5% 1/4W

R4 : 1MΩ ± 5% 1/4W

To connector (F) on Control Unit.

F-1

1

2

F-2

3

 

F-3

 

 

CONNECTOR

Plunger

NC

NO

COM

R1

 

COM

NO

 

 

 

R2

R3

R4

NC

 

Sensor Dummy Resistor Circuit

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Contents Table of Contents 520LWBefore Servicing When the testing is completed Dont Touch Before ServicingRequirements Microwave Measurement ProcedureLeakage test 520LK/R-520LW Sharp PLAZA, MahwahMicrowave Ovens ForewordDescription SpecificationGeneral Information Grounding InstructionsOven Diagram Touch Control PanelDescription of Operating Sequence Power Level P-0 to P-90 CookingOperation OFF ConditionSensor Cooking Condition MicrowaveSchematic Clock Appears on DisplayDescription and Function of Components Troubleshooting Guide Problem Test ProceduresTest Procedure Procedure Component Test Letter Magnetron Assembly TestMicrowave Output Power Procedure Component Test LetterPower Transformer Test Magnetron Temperature Fuse Test Procedure Component Test Letter High Voltage Rectifier TestCavity Temperature Fuse Test High Voltage Capacitor TestRun the oven and check all functions Replace Temperature FusePrimary Interlock Switch Test Secondary Interlock System TestProcedure Component Test Letter Monitor Switch Test Touch Control Panel Assembly TestFigure of all digits flicker KEY Unit TestCompu Defrost Test Relay TestMenu 1ST Stage 2ND Stage 3RD Stage STEAKS/CHOPS Level Time Primary on the PWB, this foil pattern acts as a fuse Steps Occurrence Cause or CorrectionAH Sensor Test Testing Method for AH Sensor AND/OR Control UnitChecking the initial sensor cooking condition R1, R2 22Ω ± 1% 1/2W R3 4.3Ω ± 5% 1/4W R4 1MΩ ± 5% 1/4W Checking Control UnitSensor Dummy Resistor Circuit Power Source Circuit Reset CircuitIndicator Circuit Synchronizing Signal CircuitDescription of LSI LSIPower source voltage Signal similar to ANI3Internal clock oscillation frequency control input setting Key strobe signalConverter power source voltage Converter power source voltage GND0VCommon data signal Operational Principle of Absolute Humidity Sensor Absolute Humidity Sensor CircuitStructure of Absolute Humidity Sensor Detector Circuit of Absolute Humidity Sensor CircuitServicing of Touch Control Panel Other PrecautionsTouch Control Panel Servicing Servicing ToolsOuter Case Removal Component Replacement and Adjustment ProcedureTo prevent an electric shock, take the following pre High Voltage Rectifier and High Voltage Capacitor Removal Power Transformer RemovalRe-install Magnetron RemovalGraphic Sheet and Membrane Switch Replacement Positive Lock Connector NO-CASE Type RemovalControl Panel Assembly Removal Oven Lamp and Lamp Socket RemovalInstallation Turntable Motor RemovalRemoval InstallationCooling FAN Motor Removal Rear ViewDoor Replacement After adjustment, check the followingAfter any service, make sure of the following RE-INSTALLSealer Film Diagram High Voltage ComponentsCircuit Control Unit Figure S-5 . Printed Wiring Board of Power Unit Parts List SCREWS,NUTS and Washers HOW to Order Replacement PartsMiscellaneous Model NumberOven and Cabinet Parts Control Panel Parts Door Parts Miscellaneous Packing and Accessories Copyright 2006 by Sharp Corporation ALL Rights Reserved

R-520LK, R-520LW specifications

The Sharp R-520LW and R-520LK are innovative microwave ovens that combine advanced technology with user-friendly features to enhance cooking experiences. Designed with modern kitchens in mind, these models embody efficiency, precision, and versatility.

One of the defining characteristics of both the R-520LW and R-520LK is their powerful 900-watt output, which allows for speedy cooking and reheating. This high wattage ensures that food is cooked evenly and retains its moisture, preventing the common issue of dry or unevenly heated meals. Furthermore, the inclusion of multiple cooking power levels provides users with flexibility, making it easy to select the ideal setting for various types of food.

Both models feature Sharp's signature Inverter Technology. Unlike traditional microwaves that use a turn-on and turn-off cycling method, inverter technology delivers a steady stream of cooking power. This results in more consistent heating, allowing delicate foods such as fish or custards to be cooked perfectly without overcooking the edges. This technology not only enhances the quality of cooked food but also improves the overall efficiency of the microwave.

The R-520LW and R-520LK come equipped with a variety of auto-cook settings that cater to different culinary needs. From popcorn to frozen vegetables, these pre-programmed settings allow users to prepare meals with just a touch of a button, making cooking uncomplicated for all skill levels. The large, user-friendly control panel features intuitive buttons and a digital display, ensuring effortless operation and visibility.

In terms of design, the R-520LW boasts a sleek white finish, while the R-520LK offers a modern black aesthetic. Both models are compact yet spacious, with a generous interior capacity that can accommodate a range of dish sizes. The turntable feature further enhances cooking efficiency by ensuring even cooking all around.

Cleaning and maintaining the R-520LW and R-520LK is a breeze, thanks to their easy-to-wipe surfaces and the interior's cavity that can be easily accessed. The durable construction of these microwaves means they are designed to withstand the rigors of daily use.

In summary, the Sharp R-520LW and R-520LK microwave ovens stand out with their advanced features, such as inverter technology and pre-programmed cooking settings, making them excellent choices for anyone looking to streamline their kitchen tasks. Their stylish designs and user-friendly interfaces further enhance their appeal, making them valuable additions to any modern home.
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