Sharp R-6R50 - Servicing

1ST LATCH SWITCH
Operation is as follows.
1. When the door is closed, the lower latch head
snaps down above the switch lever.
2. When the lower latch head pushes the switch lever.
The switch lever now depresses the plunger of the
switch closing its COM-NO contacts (ON condi-
tion).
3. When the open button is pressed, it pushes the
open lever. The open lever raises the switch lever
raising the Jower latch head.
As that time, the switch lever is released from the
piunger of the, 1st latch switch. The switch lever
is returned to its original position.
Now, the COM-NO contacts of the switch opened
(OFF condition).
2ND LATCH SWITCH
The switch is activated by the upper latch head on the
door,
When the door is opened, the switch interrupts the .
circuit to the magnetron or heating element etc., refer
to Oven Schematic Diagram for details.
STOP SWITCH
The switch is activated by the upper latch head.
The contacts are opened at the door opened and the
contacts are closed at the door closed.
MONITOR SWITCH | .
The monitor switch is activated (the COM-NC contacts
opened) by the lower latch head on the door while the
door is closed. The switch is intended to render the
oven inoperative by means of blowing the fuse(F6.3A)
when the contacts of the 1st latch switch fail to open
when the door is opened.
Function
1. When the door is opened, the monitor switch
COM-NC contacts close {to the ON condition) due ©
to their being normaily closed. At this time the 1st
latch switch 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 COM-NC contacts are first opened and then.
the 1st latch switch contacts close. (On opening
| the door, each of these switches operate inversely.)
3. If the door is opened, and the 1st latch switch
contacts fai] to open, the fuse blows simultane-
ously with closing of the monitor switch COM-NC
contacts.
CAUTION: BEFORE REPLACING A BLOWN FUSE
: TEST THE 7ST LATCH SWITCH AND
MONITOR SWITCH FOR PROPER OP-
ERATION.
(REFER TO CHAPTER “TEST PROCE-
DURE’),
NOISE FILTER UNIT
The- noise filter. unit prevents the radio-frequency: in- -. .
terference. And it has Fuse, refer to Oven Schematic
Diagram for kind of this fuse.
DESCRIPTION AND FUNCTION OF COMPONENTS
SURGE RELAY AND SURGE RESISTOR
Surge relay !s located on the relay mounting plate.
Surge resistor is located on the chassis support.
When the cooking start button is pushed at microwave
cooking or dual cooking condition, at first the surge
relay contacts close and the surge current flows
through the surge resistor. And then the surge relay
contacts open after approx. 200 msec.
The surge resistor puts down the surge current. If the
surge resistor is open or the surge relay does not op-
erate, the home breaker, home fuse, fuse 13A 250V or
fuse F6.3A 250V may break down when the cooking
Start button is pushed at microwave or dual cooking
condition.
ROTISSERIE COOKING SYSTEM .
All the surfaces of the food will be able to be grilled
uniformity by rotating the food which the skewer is
inserted into. ~
ROTISSERIE MOTOR
The rotisserie motor is located on the rotisserie motor
angle assembly which is located on the right side wall
of the oven cavity.
The skewer is rotated by the rotisserie motor through
the rotisserie motor angle assembly.
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Open bution
Figure D-1. Switch Operation
aa CAVITY
GRILL HEATING ELEMENT
FOOD
ROTISSERIE
OTO.
ASSEMBLY
COUPLING
ROLLER STAY ASSEMBLY
Figure D-2. Rottisserie Mechanism
10
R-6R50(V
R-6G50(\
R-6G52(\
R-BR70(V
SERVICING
TROUBLESHOOTING GUIDE
When troubleshooting the oven, it is helpfull to follow
the Sequence of Operation in performing the checks.
Many of the possible causes of trouble will require that
a specific test be performed. These tests are given a
procedure Jetter which will be found in the “Test Pro-
cedure” section.
IMPORTANT: If the oven becomes inoperative be-
cause of a blown fuse (F6.3A) in ist
latch & cook switch - the monitor
switch circuit, check 1st latch & cook
switch and the monitor switch before
replacing the fuse (F6.3A).
PROBLEM | POSSIBLE CAUSE | TEST PROCEDURE OR
CORRECTION
Home fuse blows when power
cord is plugged into wall recepta-
cle.
Fuse(13A 250v) blows when
power cord is plugged into wall
receptacle. (For R-6G50,
R-6G52, R-6R70)
Fuse F6.3A blows when power
cord ts plugged into wall recepta-
cle.
: 88:88 do not appear in diaplay
oa when power supply cord is
plugged into wail outlet.
Display does not operate properly
when (STOP/ CLEAR) pad
is touched.
OFF CONDITION
Shorted’ wire in power cord or wire har- | Replace cord or check wiring.
ness.
Shorted wire in wire harness.
Defective noise filter unit.
Defective monitor switch.
Shorted wire in wire harness. ~
Defective noise filter unit.(R-6R50only)
Defective touch control unit
Defective fuse 13A 250V.(For R-6G50,
R-6G52, R-6R70)
| Defective fuse F6.3A..
Defective magnetron thermal cut-out.
Defective noise filter unit.
Defective touch control unit
Defective stop switch.
Out of adjustment stop switch.
| Oven lamp does not light at door
opened.
No power at outlet.
Open wire in power cord or wire harness.
Blown fuse(F6.3A).
Blown fuse 13A 250V.(For
R-6G52, R-6R70)
Defective noise filter unit.
Defective stop switch.
Defective oven tamp.
Defective oven lamp socket.
Defective touch control unit
N ol an) <=
R-6G50,
Defective magnetron thermal cut-out.
Open or loose wire connection to
the
above components.
Check and repair harness, re-
place fuse(13A 250V).
Procedure M.
Procedure F.
Check and repair harness and
replace the fuse F6.3A. -
Procedure M.
Procedure P.
Check and replace fuse 13A
Procedure N.
Procedure H.
Procedure M.
. Procedure P.
Procedure E.
Adjust the stop switch.
Check wall outlet.
Replace or repair.
Procedure N.
Replace the fuse 13A 250V, ~
rocedure M,
rocedure E,
eplace oven lamp.
eplace oven lamp socket.
rocedure P,
rocedure H.
Replace or repair wiring. —
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