Sharp R-1480, R-1482, R-1481 Shapes of Electronic Components, Servicing of Touch Control Panel

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R-1480

R-1481

R-1482

SERVICING

1.Precautions for Handling Electronic Components This unit uses CMOS LSI in the integral part of the circuits. When handling these parts, the following precautions should be strictly followed. CMOS LSI have extremely high impedance at its input and output terminals. For this reason, it is easily influenced by the surrounding high voltage power source, static electricity charge in clothes, etc, and sometimes it is not fully protected by the built-in protection circuit.

In order to protect CMOS LSI.

1)When storing and transporting, thoroughly wrap them in aluminium foil. Also wrap all PW boards containing them in aluminium foil.

2)When soldering, ground the technician as shown in the figure and use grounded soldering iron and work table.

approx. 1M ohm

2. Shapes of Electronic Components

Transistor

DTA123ES

KRA101M

KRC243M

EC B

3.Servicing of Touch Control Panel

We describe the procedures to permit servicing of the touch control panel of the microwave oven and the precautions you must take when doing so. To perform the servicing, power to the touch control panel is available either from the power line of the oven itself or from an external power source.

(1)Servicing the touch control panel with power supply of the oven:

CAUTION:

THE HIGH VOLTAGE TRANSFORMER OF THE MI- CROWAVE OVEN IS STILL LIVE DURING SERVICING AND PRESENTS A HAZARD.

Therefore, before checking the performance of the touch control panel,

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 leads to the primary of the power transformer.

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

6)After that procedure, re-connect the power supply cord. After checking the performance of the touch control panel,

1)Disconnect the power supply cord.

2)Open the door and block it open.

3)Re-connect the leads to the primary of the power transformer.

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

5)Re-connect the power supply cord after the outer case is installed.

6)Run the oven and check all functions.

A. On some models, the power supply cord between the touch control panel and the oven itself is so short that the two can't be separated.

For those models, check and repair all the controls (sensor-related ones included) of the touch control panel while keeping it connected to the oven.

B. On some models, the power supply cord between the touch control panel and the oven proper is long enough that they may be separated from each other. For those models, it is possible to check and repair the controls of the touch control panel while keeping it apart from the oven proper; in this case you must short both ends of the door sensing switch (on PWB) of the touch control panel with a jumper, which brings about an operational state that is equivalent to the oven door being closed. As for the sensor-related controls of the touch control panel, checking them is possible if dummy resistor(s) with resistance equal to that of the controls are used.

(2)Servicing the touch control panel with power supply from an external power source:

Disconnect the touch control panel completely from the oven proper,and short both ends of the door sensing switch (on PWB) of the touch control panel,which brings about an operational state that is equivalent to the oven door being closed. Connect an external power source to the power input terminal of the touch control panel, then it is possible to check and repair the controls of the touch control panel it is also possible to check the sensor- related controls of the touch control panel by using the dummy resistor(s).

4. Servicing Tools

Tools required to service the touch control panel assembly. 1) Soldering iron: 30W

(It is recommended to use a soldering iron with a grounding terminal.)

2)Oscilloscope: Single beam, frequency range: DC - 10MHz type or more advanced model.

3)Others: Hand tools

5. Other Precautions

1)Before turning on the power source of the control unit, remove the aluminium foil applied for preventing static electricity.

2)Connect the connector of the key unit to the control unit being sure that the lead wires are not twisted.

3)After aluminium foil is removed, be careful that abnormal voltage due to static electricity etc. is not applied to the input or output terminals.

4)Attach connectors, electrolytic capacitors, etc. to PWB, making sure that all connections are tight.

5)Be sure to use specified components where high precision is required.

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Contents Over the Range Microwave Oven Table of ContentsBefore Servicing Dont Touch Before Servicing When the testing is completedMicrowave Measurement Procedure RequirementsLeakage test Foreword Sharp PLAZA, MahwahOver the Range Microwave Oven 1480 / R-1481 / R-1482Grounding Instructions Product SpecificationGeneral Information DescriptionOven Diagram Cooking Condition OperationDescription of Operating Sequence OFF ConditionPower Level P-0 to P-90 Cooking Compu CookCompu Defrost Cooking Horizontal Venting Ventilation Methods HOT AIR ExhaustVertical Venting AIR FlowFigure O-1. Oven Schematic-Off Condition Description and Function of Components Troubleshooting Guide Stirrer MotorHood Lamp Possible Case Defective Parts Power Transformer Test Test ProceduresProcedure Letter Component Test Magnetron Assembly Test Microwave Output PowerHigh Voltage Capacitor Test Procedure Letter Component TestMagnetron Temperature Fuse Test High Voltage Rectifier TestPrimary Interlock Relay RY2 Secondary Interlock Switch TestPrimary Interlock System Test Door Sensing Switch Monitor Switch TestBlown Monitor Fuse Test Hood Thermal CUT-OUT TestHood FAN Motor Test Touch Control Panel Assembly Test Before testingWHT 3 KEY Unit Test Compu Defrost Test Procedure Letter Component Test Relay TestWeight 1ST Stage 2ND Stage 3RD Stage 4TH Stage Level Time Foil Pattern on the Printed Wiring Board TestProcedure Component Test Letter Occurrence Cause or CorrectionSteps Occurrence Cause or Correction Touch Control Panel Assembly LSIIZA876DR Description of LSIDigit selection signal Signal to sound buzzerSignal coming from touch key Signal similar to P27Segment data signals Segment data signalKey strobe signal Servicing of Touch Control Panel Other PrecautionsServicing Shapes of Electronic ComponentsHood Exhaust Louver Removal Component Replacement and Adjustment ProcedureHood FAN MOTOR, Hood Duct and Oven Lamp Socket Removal Power Transformer RemovalRe-install Outer Case RemovalThermal CUT-OUT Cavity Removal Magnetron RemovalHigh Voltage Rectifier and High Voltage Capacitor Removal Hood FAN Thermal CUT-OUT RemovalTemperature Fuse Magnetron Removal Cooling FAN Motor RemovalRear View Stirrer Motor Removal Stirrer Cover and Stirrer FAN InstallationControl Panel ASSEMBLY, Control Unit and KEY Unit Removal Turntable Motor RemovalPositive Lock Connector NO-CASE Type Removal Positive lock connectorStep Door Assembly RE-INSTALL Door ReplacementAfter adjustment, check the following Door Assembly RemovalDoor Frame Door DisassemblyAfter any servicing, make sure of the following Choke CoverFigure S-1. Pictorial Diagram Circuit BFB DIPCabinet Parts Parts ListParts marked * are used in voltage more than Electric PartsDoor Parts Oven PartsModel Number HOW to Order Replacement PartsMiscellaneous SCREWS,NUTS and WashersOven and Cabinet Parts Control Panel Parts Door Parts Miscellaneous Copyright 1998 by Sharp Corporation ALL Rights Reserved Packing and Accessories

R-1481, R-1482, R-1480 specifications

Sharp R-1480, R-1481, and R-1482 are popular countertop microwave ovens that exemplify innovation in home cooking technology. These models are designed to cater to modern culinary needs, combining functionality, efficiency, and user-friendly features.

The Sharp R-1480 stands out with its powerful 900 watts of cooking power, ensuring that meals are cooked evenly and thoroughly. This model includes a spacious 1.5 cubic feet capacity, allowing users to cook larger dishes without hassle. One of the most striking features of the R-1480 is its advanced Sensor Cooking technology. This intelligent feature automatically adjusts cooking time and power levels based on the type of food being prepared, delivering optimal results with minimal effort.

The R-1481 model shares many similarities with the R-1480 but introduces additional features that enhance convenience and usability. It also boasts a 900-watt power output and a 1.5 cubic feet interior. What sets the R-1481 apart is its impressive variety of pre-programmed settings. These settings simplify cooking tasks, giving users one-touch access to options for popular foods such as popcorn, pizza, and frozen vegetables. The auto defrost function is another advantage, allowing for quick thawing of meats and seafood based on weight.

Meanwhile, the Sharp R-1482 takes the features of the R-1481 a step further, adding a few unique characteristics. This model incorporates both microwave and grill functionality, allowing for versatile cooking options. Users can enjoy the benefits of grilling their favorite dishes for a perfect finish and flavor infusion. The R-1482 also includes a user-friendly control panel with a large LCD display, ensuring easy navigation through the cooking process.

Across these models, Sharp emphasizes safety and ease of use. The child lock feature provides peace of mind for families, while the easy-to-clean stainless steel interior promotes hygiene and longevity. All models include a turntable for even cooking and reheating, making it easier to prepare meals uniformly.

In conclusion, the Sharp R-1480, R-1481, and R-1482 microwave ovens combine advanced technology with practical features, catering to a diverse range of cooking needs. These models stand as a testament to Sharp’s commitment to quality and innovation in the kitchen, making them excellent choices for anyone seeking efficiency and versatility in their cooking appliances.
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