Operating Sequence; Door Switches - Sharp R-211(W)M Service Manual

OPERATING SEQUENCE

OFF CONDITION
Closing the door activates all door interlock switches (moni-
tored latch switch and latch switch).
IMPORTANT
When the timer knob is at "0" the oven is in the OFF
condition.

DOOR SWITCHES

DOOR OPEN MECHANISM
LATCH HOOK
DOOR
LATCH
HEADS
DOOR OPEN BUTTON
Figure D-1. Door Open Mechanism
SW2: MONITOR
SWITCH
SW1: MONITORED
LATCH SWITCH
SW3: STOP SWITCH
OPEN LEVER
211M -
HIGH, MEDIUM HIGH, MEDIUM, MEDIUM
LOW, LOW COOKING
When the microwave oven is preset for variable cooking
power, the line voltage is supplied to the power transformer
intermittently within a 26-second time base through the
relay contact which is coupled with the current-limiting relay
(RY2). The following levels of microwave power are given.
SETTING
26 sec. ON
HIGH
20 sec. ON
MEDIUM HIGH
14 sec. ON
MEDIUM
8 sec. ON
MEDIUM LOW
4 sec. ON
LOW
NOTE: The ON/OFF time ratio does not exactly correspond
to the percentage of microwave power, because
approx. 3 seconds are needed for heating up the
magnetron filament.
MONITORED LATCH SWITCH (SW1)
STOP SWITCH (SW3)
1. When the oven door is closed, the contacts (COM - NO)
must be closed.
2. When the oven door is opened, the contacts (COM -
NO) must be opened.
MONITOR SWITCH (SW2)
1. When the oven door is closed, the contacts (COM - NC)
must be opened.
2. When the oven door is opened, the contacts (COM -
NC) must be closed.
3. If the oven door is opened and the contacts (COM - NO)
of the monitored latch switch (SW1) fail to open, the fuse
F8A blows simultaneously with closing the contacts
(COM - NC) of the monitor switch (SW2).
CAUTION: BEFORE REPLACING A BLOWN FUSE (F1)
TEST THE MONITORED LATCH SWITCH
(SW1), + MONITOR SWITCH (SW2) FOR
PROPER OPERATION.
4
Approx. 100% = 800 Watts
6 sec. OFF
Approx. 70% = 560 Watts
12 sec. OFF
Approx. 50% = 400 Watts
18 sec. OFF
Approx. 30% = 240 Watts
22 sec. OFF
Approx. 10% = 80 Watts