GE 240, Техническое обслуживание руководство

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Check the high voltage transformer windings for
approximate resistance value between:
Red to white (primary) - .5
Ω
Red/Black to chassis ground (secondary) - 87
Ω
Magnetron harness (
fi
lament high voltage) - .2
Ω
ELECTRICAL TERMINAL
RELEASE/LOCKING TAB
When disconnecting the primary and secondary
wire connections, note the wire locations. The wire
connectors use releasing locking tabs.
Transformer
High Voltage Transformer
WARNING:
Always be certain the capacitor
is discharged before servicing. (See
Capacitor
and Diode
.
) Use electrician's discharge pliers
and electrician's gloves under Kevlar gloves or
equivalent protective gloves when discharging the
capacitor.
Note:
The capacitor has an internal discharge
resistor that automatically discharges the capacitor
when the oven turns OFF. Under normal operation,
the capacitor should fully discharge within 30
seconds.
The transformer steps up 120 VAC line voltage to
high voltage, which is then changed to an even
higher DC voltage by the capacitor and diode.
The oven must be removed to access the high
voltage transformer. (See
Oven Removal / Partial
Removal
.
) The high voltage transformer is located
behind the top access cover. The top access cover is
held in place by 2 Phillips-head screws.
The transformer is held in place with 4 Phillips-head
screws. Two of the screws are recessed from the
top of the outer cover. Access holes are provided. A
magnetic screwdriver is necessary to capture these
screws.
Capacitor and Diode
WARNING:
Always be certain the capacitor is
discharged before servicing. Use electrician's
discharge pliers and electrician's gloves under
Kevlar gloves or equivalent protective gloves when
discharging the capacitor. Place the pliers between
the diode connection of the capacitor and the oven
chassis ground.
Note:
The capacitor has an internal discharge
resistor that automatically discharges the capacitor
when the oven turns OFF. Under normal operation,
capacitor should fully discharge within 30 seconds.
The diode works along with the capacitor to
effectively double the already-high voltage that is
provided by the power transformer. This voltage,
approximately 3000 - 5000 VDC , is applied to
the magnetron tube, causing it to produce the
microwave energy that cooks the food.
(
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)
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