Alignment And Adjustments - Samsung CM-1819 Service Manual

5. Alignment and Adjustments

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
Secondary
Filament
Primary
(Room temperature = 20˚C)
5-2 Low Voltage Transformer
1. The low voltage transformer is located on the
base plate.
2. Remove the low voltage transformer from the
base plate and check continuity.
3. Normal resistor reading is shown in the table.
5-3 Magnetron
Continuity checks can indicate only an open
filament or a short magnetron. To diagnose an
open filament or short magnetron :
1. Isolate the magnetron from the circuit by
disconnecting its leads.
2. A continuity check across the magnetron filament
terminals should indicate one ohm or less.
3. A continuity check between each filament terminal
and magnetron case should read open.
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.
Samsung Electronics
PRECAUTION
Resistance
Approx. 98Ω
Approx. 0Ω
Approx. 1.3Ω
Primary
Terminals
Terminals
1~2(input)
3~4(output 20V)
5~6(output 3.2V)
Magnetron Antenna
Filament Terminals
Secondary
Terminal
Resistance Wire
Approx. 296Ω WHT
Approx. 5.1Ω RED
Approx. 1.1Ω YEL
Gasket
Plate
Cooling Fins
19