Panasonic NN-G61 AR Microwave Oven User Manual


 
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 Diode
1. Isolate the diode assembly from the circuit by disconnecting
the leads.
2. With the ohmmeter set on the highest resistance 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-to-back resistance of the diode, otherwise
an infinite resistance may be read in both directions. A normal
diodes resistance will be infinite in one direction and several
hundred K; in the order direction.
 Magnetron
Continuity checks can only indicate an open filament or a shorted
magnetron. To diagnose for an open filament or shorted
magnetron.
1. Isolate magnetron from the circuit by disconnecting the leads.
2. A continuity check across magnetron filament terminals should
indicate one ohm or less.
3. A continuity check between each filament terminal and
magnetron case should read open.
 Membrane key board (Membrane switch assembly)
Check continuity between switch terminals, by pressing an
appropriate pad on the key board.
The contacts assignment of the respective pads on the key board
is as shown in the schematic diagram.
 Protector diode
1. Isolate the protector diode assembly from the circuit by
disconnecting its leads.
2. With the ohmmeter set on the highest resistance scale,
measure the resistance across the protector diode terminals.
Reverse the meter leads and again observe the resistance
reading. A normal protector diodes resistance will be infinite in
both directions. It is faulty if it shows continuity in one or both
directions.
COMPONENT TEST PROCEDURE
NN-G61 AR
 High voltage transformer
1. Remove connections from the transformer terminals and check
continuity.
2. Normal (cold) resistance readings should be as follows:
Secondary winding Approx. 80; ~ 120;
Filament winding Approx. 0;
Primary winding (0v ~ 230/240V) Approx. 0; ~ 3;
 High voltage capacitor
2. Check continuity of capacitor with ohmmeter on highest ohm scale.
2. A normal capacitor will show continuity for a short time, and
then indicate 9M; once the capacitor is charged.
3. A shorted capacitor will show continuous continuity.
4. An open capacitor will show constant 9M;.
(Due to internal 9M; resistor)
5. Resistance between each terminal and chassis should be infinite.
CAUTION
1. High voltage is present at the high voltage terminal of
the high voltage transformer 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.