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5. Alignment and Adjustments
PRECAUTION
1.
High voltage is present at the high voltage terminals during any cook cycle .
2.
It is neither necessary nor advisable to attempt measurement of the high voltage .
3.
Before touching any oven components or wiring, always unplug the oven from its power source and
discharge the high voltage capacitor .
5-1 High Voltage Transformer
1.
Remove connectors from the transformer terminals and
check continuity .
2.
Normal resistance readings are as follows:
Secondary
Approx. 90Ω
Filament
Approx. 0Ω
Primary
Approx. 1.2Ω
(Room temperature = 20°C)
Filament Terminals
Primary
Terminals
Secondary
Terminal
5-2 Low Voltage Transformer
1.
The low voltage transformer is located on the control
circuit board .
2.
Remove the low voltage transformer from the PCB
Ass’y and check continuity .
3.
Normal resistor reading is shown in the table .
Terminals
Resistance
1~2(Input)
1,713Ω
3~4(Output 2 .9V)
4.32Ω
5~6(Output 13V)
39.1Ω
5-3 Magnetron
1.
Continuity checks can indicate only an open filament or
a shorted magnetron. To diagnose an open filament or
shorted magnetron .
2.
Isolate the magnetron from the circuit by disconnecting its
leads .
3.
A continuity check across the magnetron filament terminals
should indicate one ohm or less .
4.
A continuity check between each filament terminal and
magnetron case should read open .
Cooling Fins
Magnetron Antenna
Gasket Plate
5-4 High Voltage Capacitor
1.
Check continuity of the capacitor with the meter set at the highest resistance scale .
2.
Once the capacitor is charged, a normal capacitor shows continuity for a short time, and then indicates 9MΩ.
3.
A shorted capacitor will show continuous continuity .
4.
An open capacitor will show constant 9MΩ.
5.
Resistance between each terminal and chassis should read infinite.
