Sharp R-2397 Asymmetric Rectifier, Exhaust Thermistor, Intake Thermistor, Magnetron Thermistor

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R-2397

FUSE F6.3A 250V

1.If the wire harness or electrical components are short- circuited, this fuse blows to prevent an electric shock or fire hazard.

2.The fuse also blows when 1st latch switch remains closed with the oven door open and when the monitor switch closes.

ASYMMETRIC RECTIFIER

The asymmetric rectifier is solid state device that pre- vents current flow is both directions. And it prevents the temperature rise of the high voltage transformer by blowing the weak point when the high voltage rectifier is shorted.

A D2 D1 B

ASYMMETRIC

RECTIFIER

CHIGH VOLTAGE RECTIFIER

The rated peak reverse voltage of D1 of the asymmetric rectifier is 6 KV The rated peak reverse voltage of D2 of the asymmetric rectifier is 1.7 KV. D1 and D2 of the asymmetric rectifier or high voltage rectifier are shorted when the each peak reverse voltage goes beyond the each rated peak reverse voltage.

1.The high voltage rectifier is shorted by some fault when microwave cooking.

2.The peak reverse voltage of D2 of the rectifier goes beyond the rated peak reverse voltage 1.7 KV in the voltage doubler circuit.

3.D2 of the rectifier is shorted.

4.The large electric currents flow through the high voltage winding of the high voltage transformer.

5.The large electric currents flow through the primary winding of the high voltage transformer.

6.The weak point blows by the large electric currents.

7.The power supplying to the high voltage transformer is cut off.

EXHAUST THERMISTOR

The thermistor is a negative temperature coefficient type. The temperature in the exhaust duct is detected through the resistance of the thermistor.

If the temperature is high, the control panel will display “EE7” and the oven will stop to avoid overheating and catching fire.

If the thermistor is open, the control panel will display "EE6" and the oven will stop.

INTAKE THERMISTOR

This thermistor detects ambient air temperature.

MAGNETRON THERMISTOR

The air temperature around the lower magnetron is detected through the resistance of the thermistor.

If the temperature is high, the control panel will display "EE17" and the oven will stop to protect the lower magnetron against overheat.

If the thermistor is open, the control panel will display "EE16" and the oven will stop.

MAGNETRON THERMAL CUT-OUTS 145˚

These thermal cut-outs protect the magnetrons against overheat. If their temperature go up higher than 145˚C because the blower motor is interrupted, the ventilation openings are blocked, the thermal cut-outs will open and the line voltage to the high voltage transformer will be cut off and the operations of the magnetrons will be stopped. The defective thermal cut-out must be replaced with new rated one.

BLOWER MOTOR THERMAL CUT-OUT 115˚C

This thermal cut-out protect the blower motor against overheat. If its temperature goes up higher than 115˚C because the blower motor is locked or the ventilation openings are blocked, the contacts of the thermal cut-out will open and the line voltage to the control unit will be cut off and the operation of the oven will be stopped. The defective thermal cut-out must be replaced with new rated one.

OVEN THERMAL CUT-OUT 115˚C

This thermal cut-out protects the oven against overheat. If the temperature goes up higher than 115˚C because the food catches fire, the contacts of thermal cut-out will open and the line voltage to the control unit will be cut off and the operation of the oven will be stopped. The defective thermal cut-out must be replaced with a new rated one.

BLOWER MOTOR

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

STIRRER MOTOR

The stirrer motor drives a stirrer antenna to stir the microwave radiation from the waveguide.

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Contents Table of Contents Commercial Microwave Oven2397 Sharp Corporation OSAKA, Japan Commercial2397 General Important InformationSpecification Product DescriptionGeneral Information DescriptionInstallation Information Display and IndicatorsAppearance View Operating KeysOperation Sequence OFF ConditionMicrowave Cooking Condition Microwave Variable CookingFunction of Important Components Asymmetric Rectifier Exhaust ThermistorIntake Thermistor Magnetron ThermistorTroubleshooting Guide ServicingRemember to Check 3D Remember to Check 4RTest Procedure Possible Cause Defective Parts Plugged into wall outletTemperature of Intake Thermistor is High Test Procedures Procedure Component Test Letter Magnetron TestMicrowave Output Power IEC-705-1988 Around 20 C Power supply Voltage Rated voltageProcedure Letter Component Test High Voltage Transformer TestCarry OUT 3D Checks Carry OUT 4R ChecksProcedure Component Test Letter Switch TestHigh Voltage Capacitor Test Carry OUT 3D Checks Weak Point A018Fuse F6.3A Test Thermal CUT-OUT Test Carry OUT 3D ChecksTable Thermal Cut-out Test Monitor Resistor Test Carry OUT 3D ChecksProcedure Component Test Letter Magnetron Thermistor Test Exhaust Thermistor TestIntake Thermistor Test Motor Winding TestKEY Unit Test Touch Control Panel Assembly TestMin Cx ± 20% Cy ± 20% 5mH Test Procedures Contd To determine if the control unit or key pad is at faultRelay Test CircuityPower Supply Circuit Power Sync Signal Generating CircuitStop Switch Circuit Exhaust Air Temperature Detecting CircuitDescription of LSI LSIIZA646DR Pin No Signal Description Internal clock oscillation frequency setting inputPower source voltage Signal coming from touch keySound Voltage level control terminal Other Precautions ServicingShapes of Electronic Components Servicing of Touch Control PanelProcedure for Entering to IC-2 Practice for checking total service counts eg 234,567 CountsTo check the contents of defrost Flicker / 0.1 sec Buzzer Other Checking and Clearing PRO CedureComponent Replacement and Adjustment Procedure Outer Case RemovalHigh Voltage Components Removal To remove the components, proceed as followsMagnetron Removal High Voltage Transformer RemovalBlower Motor Removal Stirrer Motor Upper RemovalControl Panel Assembly and Control Unit Removal HOW to Release the Positive Lock ConnectorControl Panel Assembly Removal ProcedureAfter adjustment, make sure of the following Power Supply Cord ReplacementRe-install Door Replacement and Adjustment Door ReplacementDoor Adjustment Choke Cover RemovalService Information Preparation for TestingMicrowave Measurement RequirementFigure O-1. Oven SChematic-OFF Condition High Voltage Components Circuit C d eFigure S-3. Printed Wiring Board Parts List Parts marked * are used in voltage more thanElectric Parts Cabinet PartsVCEAB31HW104M Oven Parts Door PartsMiscellaneous SCRE, Nuts and WashersHOW to Order Replacement Parts Model NumberREF. no DescriptionOven and Cabinet Parts Control Panel Parts Door Parts Not replaceable items 2397

R-2397 specifications

The Sharp R-2397 is a high-performance microwave oven that combines advanced technology with user-friendly features, making it a popular choice for modern kitchens. This model stands out due to its sleek design and efficient functionality, catering to both cooking enthusiasts and busy households alike.

One of the most notable features of the Sharp R-2397 is its powerful microwave cooking capabilities. With a wattage rating of 900 watts, it ensures that food is cooked evenly and quickly, allowing users to prepare meals in a fraction of the time compared to conventional ovens. The unit also offers multiple power levels, enabling precise cooking adjustments for various types of food, from defrosting to reheating and everything in between.

Another key characteristic of the R-2397 is its spacious interior. With a generous capacity of 23 liters, this microwave can accommodate larger dishes, making it suitable for families or individuals who enjoy hosting gatherings. The turntable feature promotes even cooking by rotating food continuously, ensuring that every inch is heated uniformly.

Additionally, the Sharp R-2397 is equipped with a range of convenient presets and auto-cook functions. These pre-programmed settings allow users to optimize cooking times for common dishes, such as popcorn, vegetables, and frozen meals, simplifying meal preparation and enhancing user experience. The intuitive control panel is designed to be user-friendly, ensuring that anyone can operate the microwave with ease.

Safety is also a significant consideration in the design of the Sharp R-2397. The unit comes with a child lock function, preventing accidental operation and ensuring that the oven is used safely in households with young children. This feature adds peace of mind for parents while using the appliance in their daily routines.

Moreover, the R-2397 incorporates a modern aesthetic that can fit into various kitchen styles. Its polished exterior and compact design make it both attractive and practical, with the added advantage of easy cleaning and maintenance.

In summary, the Sharp R-2397 is a versatile microwave oven that offers a blend of power, efficiency, and user-centric features. With its high wattage, spacious interior, smart presets, and safety measures, it is an excellent addition to any kitchen, catering to everyday cooking needs and helping to simplify meal times. Whether reheating leftovers or cooking a new recipe, the Sharp R-2397 sets itself apart as a reliable kitchen companion.
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