Sharp R-2397 FUSE F6.3A, Asymmetric Rectifier, Exhaust Thermistor, Intake Thermistor

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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