Samsung CE287ASTR, Service Manual

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1-2 Special Servicing Precautions (Continued)

17. When checking the continuity of the witches or 

transformer, always make sure that the power is 

OFF, and one of the lead wires is disconnected.

18. Components that are critical for safety are  

indicated in the circuit diagram by shading,         

        or         .

19. Use replacement components that have the 

same ratings, especially for flame resistance and 

dielectric strength specifications. A replacement 

part that does not have the same safety charac-

teristics as the original might create shock, fire or 

other hazards.

NOTE

 : Connect the oven to a 20A. When  

connecting the oven to a 15A, make sure 

that circuit breaker can operate. 

1. High Voltage Warning Do not attempt to measure 

any of the high voltages --this includes the fila-

ment voltage of the magnetron. High voltage is 

present during any cook cycle. 

Before touching any components or wiring, always 

unplug the oven and discharge the high voltage 

capacitor (See Figure 1-1)

2. The high-voltage capacitor remains charged about 

30 seconds after disconnection. Short the nega-

tive terminal of the high-voltage capacitor to to the 

oven chassis. (Use a screwdriver.)

3. High voltage is maintained within specified limits 

by close-tolerance, safety-related components 

and adjustments. If the high voltage exceeds the 

specified limits, check each of the special compo-

nents.

H. V. Diode

Short

H. V. Capacitor

Fig. 1-1 Discharging High Voltage Capacitor

Touch chassis ground first then short to the high voltage 

capacitor terminal by using screwdriver or jumper wire.

PRECAUTION

There exists HIGH VOLTAGE ELECTRICITY with 

high current capabilities in the circuits of the HIGH 

VOLTAGE TRANSFORMER secondary and fila-

ment terminals. It is extremely dangerous to work 

on or near these circuits with the oven energized.
DO NOT measure the voltage in the high voltage 

circuit including filament voltage of magnetron.

PRECAUTION

Never touch any circuit wiring with your hand nor 

with uninsulated tool during operation.

PRECAUTION

Servicemen should remove their watches when-

ever working close to or replacing the magnetron.

1-3 Special High Voltage Precautions