5
R-2275
R-2285
COMMERCIAL
FREQUENCY
(50HZ)
POWER OUTPUT
BY MAGNETRON 1
POWER OUTPUT
BY MAGNETRON 2
OPERATION OF
MAGNETRON
Figure S-1. High Voltage Circuit
FUNCTION OF IMPORTANT COMPONENTS
DOOR OPEN MECHANISM
1. The door release lever is pulled.
2. The upper latch head is lifted up by the linked door
release lever.
3. The latch lever is lifted up by the door release lever.
4. The joint lever is lifted up by the latch lever.
5. The lower latch head is lifted up by the joint lever.
6. Now both latch heads are lifted up, so they can be
released from the latch hook.
7. Now the door can be opened.
MONITOR SWITCH SW4
The monitor switch is activated (the contacts opened) the
upper latch head and switch lever A while the door is closed.
The switch is intended to render the oven inoperative by
means of blowing the fuse F2 F6.3A when the contacts of the
1st latch switch SW1 fail to open when the door is opened.
Function
1. When the door is opened, the monitor switch SW4
contacts close (to the ON condition) due to their being
normally closed. At this time the 1st latch switch SW1 is
in the OFF condition (contacts open) due to their being
normally open contact switches.
2. As the door goes to a closed position, the monitor switch
contacts are opened and 1st latch switch contacts are
closed (On opening the door, each of these switches
operate inversely.)
3. If the door is opened and the 1st latch switch contacts fail
to open, the fuse F2 F6.3A blows simultaneously with
closing of the monitor switch contacts.
CAUTION: BEFORE REPLACING A BLOWN FUSE F2
F6.3A TEST THE 1ST LATCH SWITCH, MONI-
TOR SWITCH AND MONITOR RESISTOR FOR
PROPER OPERATION. (REFER TO CHAP-
TER “TEST PROCEDURE”).
MONITOR RESISTOR
The monitor resistor prevents the fuse F2 F6.3A 250V
bursting when the fuse F2 F6.3A 250V blows due to the
operation of the monitor switch.
NOISE FILTER
The noise filter assembly prevents radio frequency interfer-
ence that might flow back in the power circuit.
SPECIAL FUSE / WEAK POINT F1
If the wire harness or electrical components are short-
circuited, this special fuse / weak point F1 blows to prevent
an electric shock or fire hazard.
Figure D-1.Door Open Mechanism
1ST LATCH SWITCH SW1, 2ND LATCH SWITCH SW2,
3RD LATCH SWITCH SW3 AND STOP SWITCH SW5
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.
T2: POWER TRANSFORMER
ASYMMETRIC
RECTFIER
D: H.V. RECTIFIER
C2: CAPACITOR
AC 2100V
MG2: MAGNETRON
T1: POWER TRANSFORMER
ASYMMETRIC
RECTFIER
D: H.V. RECTIFIER
C1: CAPACITOR
AC 2100V
MG1: MAGNETRON
Figure S-2. Operation of Magnetron
Door release
lever
Latch head
Latch lever
Joint
lever
Latch head
Monitor switch
3rd. latch switch
Stop switch
Latch hook
1st. latch switch
2nd. latch switch