R-641AM - Sharp Home Appliance Service Manual (repair manual). Page 4

4

R-641M -

Closing the door activates all door interlock switches
(Monitored latch switch, and stop switch.)

When the microwave oven is preset for variable cooking
power, the 240 volts is supplied to the high voltage
transformer intermittently within a 32-second time base
through the relay contact which is coupled with the
current-limiting relay RY3. The following levels of micro-
wave power are given.

SETTING

32 sec. ON

24 sec. ON

18 sec. ON

12 sec. ON

6 sec. ON

8 sec. OFF

14 sec. OFF

20 sec. OFF

28 sec. OFF

HIGH

MEDIUM
 HIGH

MEDIUM

MEDIUM 
LOW

LOW

Approx. 70%

Approx. 50%

Approx. 30%

Approx. 10%

Note:

The On/Off time ratio does not exactly corre-
spond to the percentage of microwave power,
because  approx. 2 seconds  are needed for
heating up the magnetron filament.

100%

26 sec. OFF

LATCH HOOK

STOP SWITCH

MONITORED
LATCH SWITCH

MONITOR SWITCH

LATCH
HEADS

OPEN LEVER

DOOR OPEN BUTTON

DOOR

The door can be opened by pushing the open button on
the control panel. When the open button is pushed, the
open lever pushes lower latch head on the door upward.
The latch head is linked with the lower latch head, so now,
the door can be opened.