Alignment And Adjustments - Samsung M1874NR 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:
Secondary Approx. 121 Ω
Filament Approx. 0 Ω
Primary Approx. 1.7 Ω
(Room temperature = 20∞ C)
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.
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.
PRECAUTION
Primary
Terminals
Terminals
1~2(Input)
3~4(Output 2.9V)
5~6(Output13V)
Magnetron Antenna
Cooling Fins
- 9 -
Filament Terminals
Secondary
Terminal
Resistance
Ω
1,000. .
Ω
3.947. ..
Ω
2.117. .
Gasket Plate