Samsung CM1929, Service Manual

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15
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:
Terminal Resistance
Secondary Approx . 98 Ω
Filament Approx . 0 Ω
Primary Approx . 1 .3 Ω
(Room temperature = 20°C)
Primary
Terminals
Secondary
Terminal
5-2 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
5-3 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.