Daewoo KOR-145M0P, Руководство по обслуживанию

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1. High voltage is present at the high voltage terminal of the high voltage transformer during any cooking 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
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. 100
Ω
± 10%
Filament winding . . . . . . . . . . . . . . .Approx. 0
Ω
Primary winding . . . . . . . . . . . . . . . .Approx. 1.5
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 10M
Ω
once the capacitor is
charged.
(C) A shorted capacitor will show continuous continuity.
(D) An open capacitor will show constant 10M
Ω
.
(E) Resistance between each terminal and chassis should
be infinite.
3. High voltage diode
(A) Isolate the diode from the circuit by disconnecting the
leads.
(B) With the ohmmeter set on the highest resistance
scale, measure the resistance across the diode
terminals.
Reverse the meter leads and again observe the resis-
tance reading. Meter with 6V, 9V or higher voltage
batteries should be used to check the frontback resis-
tance of the diode, otherwise an infinite resistance may
be read in both directions. A normal diode resistance
will be infinite in one direction and several hundred K
Ω
in the other direction.
4. Magnetron
For complete magnetron diagnosis, refer to “Measure-
ment of the Microwave Output Power”.
Continuity checks can only indicate and open filament
or a shorted magnetron.
To diagnose for an open filament or shorted , magnetron.
(A) Isolate magnetron from the circuit by disconnecting
the leads.
(B) A continuity check across magnetron filament
terminals should indicate 0.1ohm or less.
(C) A continuity check between each filament terminal
and magnetron case should read open.
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 open 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 replacement.