Goldstar MA-2005ST 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

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

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

P =

4187 x (ÆT)

T

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 the lowest position and the

microwave power switched on.

¥ The time T for the temperature of the water to rise by a

value Æ T of (10±2)¡K is measured, where T is the time

in seconds and ÆT 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.

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 leadwire from RELAY (RY2) of the

PCB SUB ASSÕY.

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

PCB SUB ASSÕY.

4)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

Lift up and pull out control panel

5-3

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Contents Microwave Oven Safety Precautions How a Microwave Oven Works Function & Type 1/2Type of Microwave Oven Grill Cooking Function & Type 2/2Installation Installation & Utensils 1/2Cooking Utensils Installation & Utensils 2/2History of dielectric heating What’s the microwave? 1/2Principle of dielectric heating What’s the microwave? 2/2 Safety of microwave ovenDefinition of electric wave Conventional heating Conventional heating vs. dielectric heatingCavity Construction of microwave ovenDoor ControllerHow does the microwave oven operate? Input Senondary Winding AT Microwave generation systemMagnetron 1/2 Microwave generation systemMagnetron 2/2 Testing Magnetron TubeMultiwave system What is Multi-WaveWhat’s the infrared sensor? Infrared sensorWhat’s does move automatically? Auto moving heaterConventional Heater LG’s Auto Moving HeaterSpecifications Control Panel FeaturesOperating Sequence Schematic Circuit Description Microwave Leakage Test Tools and Measuring InstrumentsNecessary Tools Necessary Measuring InstrumentsMeasurement with a Fully Assembled Oven Measurement with Outer Case RemovedRecord Keeping and Notification After Measurement Disassembly and Adjustment Measurement of Microwave Power OutputPower Supply Cord Control Panel AssemblyDoor Main Assembly Removal PCB Assembly RemovalMagnetron Removal AIR Duct Assembly RemovalRemoving the Turntable Motor High Voltage Transformer Removal FAN Motor Assembly RemovalHigh Voltage Capacitor and Diode Removal Interlock SystemSecondary Interlock Switch Test Primary Interlock Switch TestMonitor Switch Test Interlock Continuity TestComponents Test Procedure Component Test ProcedureComponents Test Procedure Results Relay Condition Cause Remedy Trouble ShootingResult Result Condition Check Defective PCB assembly Defective high voltage transformer Introduction Exploded ViewDoor Parts Controller Parts Oven Cavity Parts Latch Board Parts Interior Parts Base Plate Parts Schematic Diagram of P.C.B Printed Circuit Board