Circuit Description - Panasonic NE-7910 Service Manual

CIRCUIT DESCRIPTION
Refer to the schematic diagram on page 11.
1.
{A}
(B)
{C)
(A)
(B)
(C)
(A)
(B)
(C)
(A)
(B)
{C)
(D)
(E)
When the food is placed inside the oven and door is closed.
The low voltage transformer supplies the necessary voltage to the digital programmer circuit when power cord is
plugged in. se
The contacts of the short switch open. This switch creates short circuit to blow 15 A fuse and stop magnetron oscilla-
tion when door is opened during operation under abaornial condition, {i.e. both the contacts of latch switch A and B
do not open the circuit to stop oscillation.)
The door keyes are caught by the door hooks, the contacts of latch switch A and B close the primary circuit.
When cooking power and cooking time are set by tapping the power pad (button) and the desired
numerical pads (buttons).
Power indicator light turns on to indicate that power has been set.
The time you set appears in the display window.
The digital programmer circuit memorizes the functions set.
When auto sensor cooking is set by tapping the auto sensor contro! pad.
Auto indicator light turns on.
The selected auto program appears in the display window.
The digital programmer circuit memorizes the information that the auto sensor cooking has been set.
When the start pad (button) is tapped.
115V A.C. is applied to the high voltage transformer through power relay which is energized by the digital programmer
circuit.
Fan motor starts rotating and cools the magnetron by blowing the air coming from the intake on the back panel over
the magnetron fins. Also the fan motor drives the turntable by means of gears, belts and pulleys for uniform cooking.
(See fig. 8)
Fan motor
MAGNET POLARITY
Turntable Magnet
Ee
Pulley D
Oven bottom wail
(Fig. 8)
The oven lamp turns on.
Power (or defrost, auto indicator) indicator light selected starts blinking to indicate magnetron oscillation.
20V A.C. is supplied to the digital programmer circuit from the high voltage transformer.
=12—