Daewoo KOG-261M, Руководство по обслуживанию

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1. High voltage is present at the high voltage terminal of the high voltage transformer during any cook-
ing 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 capacitor (see page 20).
5. Interlock monitor switch
The interlock switch can be checked with an ohmmeter. Isolate the switch and then connect the
meter leads to the common (COM) and normally close (NC) terminals of the switch. The meter
should indicate an open circuit with the door closed and a closed circuit with the door opened.
6. Primary and secondary interlock switch
The primary and secondary interlock switch can be checked with an ohmmeter. Isolate the switch
and connect the meter leads to the common (COM) and normally open (NO) terminals of the
switch.
The meter should indicate an openn circuit with the door opened and a closed circuit with the door
closed. In case improper operation is indicated, make the necessary switch adjustment or replace-
ment.
COMPONENT TEST PROCEDURE
1. High voltage transformer
(A) Remove connections from the transformer
terminals and check continuity.
(B) Normal readings should be as follows:
Secondary winding ..........Approx. 90
Ω
±10%
Filament winding.........................Approx. 0
Ω
Primary winding ..........................Approx. 0
Ω
2. High voltage capacitor
(A) Check continuity of capacitor with meter on
the highest OHM scale.
(B) A normal capacitor will show continuity for a
short time, and then indicate 9M
Ω
once the
capacitor is charged.
(C) A shorted capacitor will show continuous
continuity.
(D) An open capacitor will show constant 9M
Ω
.
(E) Resistance between each terminal and
chassis should be infinite.
3. High voltage diode
(A) Isolate the diode from the circuit by discon-
necting the leads.
(B) With the ohmmeter set on the highest resis-
tance scale, measure the resistance across
the diode terminals.
Reverse the meter leads and again observe
the resistance reading. meter with 6V, 9V or
higher voltage batteries should be used to
check the front-back resistance of the diode,
otherwise an infinite resistance may be read
in both directions. A normal diodes resis-
tance will be infinite in one direction and sev-
eral hundred K
Ω
in the other direction.
4. Magnetron
For complete magnetron diagnosis, refer to
“Measurement of the Microwave Output
Power”. (Page 34) Continuity checks can
only indicate and open filament or a shorted
magnetron. To diagnose for an open fila-
ment or shorted magnetron.
(A) Isolate magnetron from the circuit by dis-
conecting the leads.
(B) A continuity check across magnetron fila-
ment terminals should indicate ohm or less.
(C) A continuity check between each filament
terminal and magnetron case should read