Electrolux E30MO65GSSB, Техническое и сервисное руководство

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Operation
2-1
The following is a description of component functions
during oven operation.
OFF CONDITION
Closing the door activates the door sensing switch and
secondary interlock switch. (In this condition, the monitor
switch contacts are opened.) When oven is plugged in,
117 volts AC is supplied to the control unit. (Figure 2-1).
1. The display will show “WELCOME, PRESS CLEAR”.
To set any program or set the clock, you must first
touch the STOP/CLEAR button. The display will
clear, and “ : “ appears.
NOTE: When the door is opened, the oven lamp comes
on.
2. A signal is input to the control unit, energizing the
coil of shut-off relay (RY-4). RY-4 contacts close,
completing a circuit to the damper motor. The
damper motor now operates moving the damper to
the open position, thereby closing the contacts of the
damper switch, which inputs a signal to the control
unit. The coil of relay RY-4 is de-energized, opening
its contacts, thereby turning off the damper motor.
COOKING CONDITION
Program desired cooking time by touching the NUMBER
pads. Program the power level by touching the POWER
LEVEL pad and then a NUMBER pad.
When the START pad is touched, the following operations
occur:
1. The contacts of relays are closed and components
connected to the relays are turned on as follows.
(For details, refer to Figure 2-2)
RELAY CONNECTED COMPONENTS
RY-1 Oven lamp/Turntable motor
RY-2 Power transformer
RY-3 Heating element
RY-4 Damper motor
RY-5 Convevtion motor
RY-6 Fan motor
2. 117 volts AC is supplied to the primary winding of
the power transformer and is converted to about
3.0 volts AC output on the filament winding, and
approximately 2360 volts AC on the high voltage
winding.
3. The filament winding voltage heats the magnetron
filament and the H.V. winding voltage is sent to a
voltage doubler circuit.
4. The microwave energy produced by the magnetron
is channeled through the waveguide into the cavity
feedbox, and then into the cavity where the food
is placed to be cooked.
5. Upon completion of the cooking time, the third
transformer, oven lamp, etc. are turned off, and the
generation of microwave energy is stopped. The
oven will revert to the OFF condition.
6. When the door is opened during a cook cycle, the
third door switch, monitor switch, door sensing switch,
secondary interlock relay and primary interlock switch
are activated with the following results. The circuits
to the turntable motor, the cooling fan motor, and the
high voltage components are de-energized, the oven
lamp remains on, and the digital read-out displays the
time still remaining in the cook cycle when the door
was opened.
7. The monitor switch is electrically monitoring the
operation of the relay (RY1) and the primary interlock
switch and is mechanically associated with the door
so that it will function in the following sequence.
(1) When the door opens from a closed position, the
door sensing switch and the primary interlock
switch open their contacts, and then the
monitor switch contacts close and then the third
door switch contacts open.
(2) When the door is closed from the open position,
the monitor switch contacts open and the
third door switch contacts close first, and then the
contacts of the primary interlock switch and the
and the door sensing switch close.
If the relay (RY1) and the primary interlock switch fail
with their contacts closed when the door is opened, the
closing of the monitor switch contacts will form a short
circuit through the monitor fuse, the relay (RY1) and
the primary interlock switch, causing the monitor fuse to
blow.
Operating Sequence Description