Frigidaire LCRT2010ST Measurement of Microwave Power Output, Disassembly and Adjustment

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MEASUREMENT OF MICROWAVE POWER OUTPUT

Microwave power output measurement is made with the microwave oven supplied at its rated voltage and operated at its maximum microwave power setting with a load of (1000±5) g of potable water.

The water is contained in a cylindrical borosilicate glass vessel having a maximum material thickness of 3 mm and an outside diameter of approximately 190mm.

The oven and the empty vessel are at ambient temperature prior to the start of the test.

The initial temperature (T1) of the water is (10±2)°C. It is measured immediately before the water is added to the vessel. After addition of the water to the vessel, the load is immediately placed on the center of the turntable which is in thd lowest position and the microwave power switched on.

The time T for the temperature of the water to rise by a value T of (10±2)°K is measured, where T is the time in seconds and T is the temperature rise. The initial and final water temperatures are selected so that the maximum difference between the final water temperature and the ambient temperature is 5°K.

The microwave power output P in watts is calculated from the following formula :

4187 x (T) + 0.55 X (T2 - T0 ) X M

P =

T

T2: Temperature after heating

T0: Temperature of bowl

M: Weight of bowl

is measured while the microwave generator is operating at full power. Magnetron filament heat-up time is not included. (about 3 sec)

The water is stirred to equalize temperature throughout the vessel, prior to measuring the final water temperature.

Stirring devices and measuring instruments are selected in order to minimize addition or removal of heat.

WATER LOAD

TURNTABLE

DISASSEMBLY AND ADJUSTMENT

A. OUTER CASE REMOVAL

1)Disconnect the power supply cord from the outlet.

2)Remove the screws from the rear of the case.

The outer case must be moved backward to be lifted off.

B. POWER SUPPLY CORD

1)Remove the outer case.

2)Disconnect two terminals and remove one screw of the ground terminal.

C.CONTROL PANEL ASSEMBLY

1)Open the door.

2)Disconnect the lead wire from RELAY (RY2) of the

PCB SUB ASSEMBLY.

3)Disconnect the leadwire from connector (CN1) of the

PCB SUB ASSEMBLY.

4)Remove screw which hold the controller assembly to the cavity.

5)Lift up and pull out control panel assembly carefully from the cavity.

CAUTION: DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE SERVICING (refer to page 2-1)

Remove the screw

ground

screw

securing

screw

Lift up and pull out control panel

5-3

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Contents Microwave Oven Microwave Radiation Safety PrecautionsContents Description SpecificationsAntenna Microwave RadiationInstalling InstallationsGrounding Instructions Operating Instructions FeaturesControl Panel Operating Sequence Schematic Diagram General Details Circuit DescriptionTools and Measuring Instruments Service InformationMicrowave Leakage Test Special TIP Record Keeping and Notification After MeasurementDisassembly and Adjustment Measurement of Microwave Power OutputPower Supply Cord Control Panel AssemblyDoor Main Assembly / Removal PCB Assembly RemovalMagnetron Removal AIR Duct Assembly / RemovalRemoving Sensor Removing the Turntable Motor FAN Motor Assembly RemovalHigh Voltage Transformer Removal High Voltage Capacitor and Diode RemovalInterlock Mechanism Interlock SystemSecondary Interlock Switch Test Primary Interlock Switch TestMonitor Switch Test Components Test Procedure ResultsComponents Test Procedure Component Test ProcedureFilament Winding Primary Terminal MagnetronCapacitor High VoltageDiode Relay PowerLevel FAN MotorCondition Cause Remedy Trouble ShootingCheck Result Cause ConditionCondition Check Result Cause Remedy Malfunction of secondary switchSetting time does not count down when touching Start pad Check Result Introduction Exploded ViewDoor Parts Controller Parts Oven Cavity Parts Latch Board Parts 50FZZA Interior PartsBase Plate Parts Sensor Parts