Sharp R-1480, R-1482, R-1481 service manual Description and Function of Components

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R-1480

R-1481

R-1482

DESCRIPTION AND FUNCTION OF COMPONENTS

DOOR OPEN MECHANISM

The door is opened by pulling the door handle, refer to the Figure D-1.

Latch

Hook

Latch

Heads

Door

Sensing

Switch

Monitor

Fuse

Door

Monitor

 

Switch

Secondary

Interlock

Switch

Figure D-1. Door Open Mechanism

CAUTION: BEFORE REPLACING A BLOWN MONITOR FUSE TEST THE DOOR SENSING SWITCH, PRIMARY INTERLOCK RELAY (RY2), SEC- ONDARY INTERLOCK SWITCH AND MONI- TOR SWITCH FOR PROPER OPERATION. (REFER TO CHAPTER "TEST PROCEDURE").

NOTE: MONITOR FUSE AND SWITCH ARE REPLACED AS AN ASSEMBLY

TEMPERATURE FUSE (MG)

The temperature fuse located near the waveguide is designed to prevent damage to the magnetron if an over heated condition develops in the tube due to cooling fan failure, obstructed air guide, dirty or blocked air intake, etc. Under normal operation, the temperature fuse remains closed. However, the temperature fuse will open at 302˚F (150˚C) causing the oven to shut down.

THERMAL CUT-OUT (HOOD )

DOOR SENSING AND SECONDARY INTERLOCK SWITCHES

The secondary interlock switch is mounted in the lower position of the latch hook and the door sensing switch in the primary interlock system is mounted in the upper position of the latch hook. They are activated by the latch heads on the door. When the door is opened, the switches interrupt the circuit to all components. A cook cycle cannot take place until the door is firmly closed thereby activating both inter- lock switches. The primary interlock system consists of the door sensing switch and primary interlock relay located on the control circuit board.

MONITOR SWITCH

The monitor switch is activated (the contacts opened) by the latch head on the door while the door is closed. The switch is intended to render the oven inoperative by means of blowing the monitor fuse when the contacts of the primary interlock relay (RY2) and secondary interlock switch fail to open when the door is opened.

Functions:

1.When the door is opened, the monitor switch contact close (to the ON condition) due to their being normally closed. At this time the primary interlock relay (RY2) and secondary interlock switch are in the OFF condition (contacts open) due to their being normally open contact switches. And the contacts of relay (RY1) are in the ON condition (contacts close).

2.As the door goes to a closed position, the monitor switch contacts are first opened and then the door sensing switch and the secondary interlock switch contacts close. (On opening the door, each of these switches operate inversely.)

3.If the door is opened, and the primary interlock relay (RY2) and secondary interlock switch contacts fail to open, the monitor fuse blows simultaneously with closing of the monitor switch contacts.

This thermal cut-out located on the right base plate. It is designed to automatically turn on the hood fan motor whenever the hot air rising from the conventional range below causes the temperature at the thermal cut-out to rise to 140˚F (60˚C) or higher, thus removing this hot air from around microwave oven. When the temperature around the thermal cut-out drops to 113˚F (45˚C) or lower, the thermal cut-out shuts off the hood fan motor.

THERMAL CUT-OUT (CAVITY )

This thermal cut-out is located on the top of the oven cavity. It is designed to prevent damage to the oven unit if the food in the oven catches fire due to overheating produced by improper setting of cooking time or failure of control unit.

Under normal operation, the thermal cut-out remains closed. However, the thermal cut-out will open at 293˚F (145˚C) causing the oven to shut down.

TURNTABLE MOTOR

The turntable motor rotates the turntable located on the bottom of the oven cavity, so that the foods on the turntable cook evenly during cooking. Turntable will turn in either direction. The turntable motor can be turned off by touching TURNTABLE ON/OFF pad.

COOLING FAN MOTOR

The cooling fan motor drives a blade which draws external cool air. This cool air is directed through the air vanes surrounding the magnetron and cools the magnetron. This air is channelled through the oven cavity to remove steam and vapors given off from the heating foods. It is then exhausted through the exhausting air vents at the oven cavity.

HOOD FAN MOTOR

The hood fan motor is a two-speed, single-phase, double pole induction type, requiring a hood fan capacitor. It is located outside the upper rear part of the oven cavity, is to remove, from around the oven, hot air rising from the conventional electric or gas range over which it is installed.

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Contents Table of Contents Over the Range Microwave OvenBefore Servicing When the testing is completed Dont Touch Before ServicingMicrowave Measurement Procedure RequirementsLeakage test Sharp PLAZA, Mahwah Over the Range Microwave Oven1480 / R-1481 / R-1482 ForewordProduct Specification General InformationDescription Grounding InstructionsOven Diagram Operation Description of Operating SequenceOFF Condition Cooking ConditionPower Level P-0 to P-90 Cooking Compu CookCompu Defrost Cooking Ventilation Methods HOT AIR Exhaust Vertical VentingAIR Flow Horizontal VentingFigure O-1. Oven Schematic-Off Condition Description and Function of Components Troubleshooting Guide Stirrer MotorHood Lamp Possible Case Defective Parts Test Procedures Procedure Letter Component Test Magnetron Assembly TestMicrowave Output Power Power Transformer TestProcedure Letter Component Test Magnetron Temperature Fuse TestHigh Voltage Rectifier Test High Voltage Capacitor TestSecondary Interlock Switch Test Primary Interlock System Test Door Sensing SwitchMonitor Switch Test Primary Interlock Relay RY2Blown Monitor Fuse Test Hood Thermal CUT-OUT TestHood FAN Motor Test Touch Control Panel Assembly Test Before testingWHT 3 KEY Unit Test Procedure Letter Component Test Relay Test Weight 1ST Stage 2ND Stage 3RD Stage 4TH Stage Level TimeFoil Pattern on the Printed Wiring Board Test Compu Defrost TestProcedure Component Test Letter Occurrence Cause or CorrectionSteps Occurrence Cause or Correction Touch Control Panel Assembly Description of LSI LSIIZA876DRSignal to sound buzzer Signal coming from touch keySignal similar to P27 Digit selection signalSegment data signals Segment data signalKey strobe signal Other Precautions ServicingShapes of Electronic Components Servicing of Touch Control PanelComponent Replacement and Adjustment Procedure Hood Exhaust Louver RemovalPower Transformer Removal Re-installOuter Case Removal Hood FAN MOTOR, Hood Duct and Oven Lamp Socket RemovalMagnetron Removal High Voltage Rectifier and High Voltage Capacitor RemovalHood FAN Thermal CUT-OUT Removal Thermal CUT-OUT Cavity RemovalTemperature Fuse Magnetron Removal Cooling FAN Motor RemovalRear View Stirrer Cover and Stirrer FAN Installation Control Panel ASSEMBLY, Control Unit and KEY Unit RemovalTurntable Motor Removal Stirrer Motor RemovalPositive Lock Connector NO-CASE Type Removal Positive lock connectorStep Door Replacement After adjustment, check the followingDoor Assembly Removal Door Assembly RE-INSTALLDoor Disassembly After any servicing, make sure of the followingChoke Cover Door FrameFigure S-1. Pictorial Diagram Circuit DIP BFBParts List Parts marked * are used in voltage more thanElectric Parts Cabinet PartsOven Parts Door PartsHOW to Order Replacement Parts MiscellaneousSCREWS,NUTS and Washers Model NumberOven and Cabinet Parts Control Panel Parts Door Parts Miscellaneous Packing and Accessories Copyright 1998 by Sharp Corporation ALL Rights Reserved

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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