View Sharp R-8740 (serv.man10) Service Manual online
2. Make sure that a definite” click” can be heard when the
closed position with one hand, then push the door open
button with the other, this causes the latch leads to rise,
it is then possible to hear a “click’ as the door switches
ating the oven.
Do not operate the oven if any of the following conditions
2. Door hinge, support or latch hook is damaged.
3. The door gasket or seal is damaged.
4. The door is bent or warped.
5. There are defective parts in the door interlock system.
6. There are defective parts in the microwave generating
1. Without the RF gasket (Magnetron).
2. If the wave guide or oven cavity are not intact.
3. If the door is not closed.
4. If the outer case (cabinet) is not fitted.
1. Disconnect oven from power supply.
2. Open the oven door and wedge it open.
3. Remove backplate.
4. Remove the screws from rear and along the side edge of
2. Remove outer wrap.
3. Disconnect wiring panel.
2. Disconnect the filament leads of high voltage transformer
7. Now the high voltage transformer is free.
N.B.; Step 1, 2 and 6 form the basis of the 3D checks.
1. CARRY OUT 3D CHECKS
2. Disconnect all the leads and terminals of high voltage
THE CATHODE (EARTH) CONNECTION IS
SECURELY FIXED TO THE CAPACITOR
HOLDER WITH AN EARTHING SCREW.
7. Now high voltage rectifier assembly and capacitor should
around the antenna.
2. Disconnect the H.V. wire B and filament lead of the
5. Carefully remove four (4) screws holding magnetron to
magnetron to prevent it from falling.
to the oven cavity back plate.
oven cavity back plate.
the following procedure.
1) Hold the edge of the rotor of the fan motor by using
• Make sure that no swarf from the rotor enters
• Do not reuse the removed fan blade as the
of the fan motor on the flat table.
the fan blade with a small, light weight, ball peen
hammer or rubber mallet.
because the bracket may be deformed.
one (1) screw.
with the one (1) screw.
support with the one (1) screw.
AND THE MAGNETRON MOUNTING
SCREWS ARE TIGHTENED SECURELY.
where should be pinched
2. Remove wire leads as positive lock connector
3. Lift up the oven lamp from its retaining clips.
4. Now, the oven lamp is free.
2. Pushing the lever of positive lock
NECT THE POSITIVE LOCK
7. Remove the one (1) nut holding the convection fan,
10. Remove the two (2) screws holding the convection motor
2. Remove the two (2) screws holding the back plate to oven
4. Remove the two (2) screws holding the convection fan
1. CARRY OUT 3D CHECKS.
2. Remove the one (1) screw holding the green/yellow wire
5. Now, the power supply cord is free.
1. Insert the moulding cord stopper of power supply cord
Figure C-4 (b).
2. Disconnect the wire leads to the grill heating element.
3. Remove the two(2) screws holding the exhaust duct
2. Remove the control panel assembly referring to
4. Remove the two (2) screws holding the latch hook to the
6. Push the retaining tab slightly and remove the switch.
operate properly due to a mis-adjustment, the following
of (COM.- NO.) open and contacts of (COM.- NC.) close
when the door is opened.
meter. (Refer to Microwave Measurement Procedure.)
1. CARRY OUT 3D CHECKS
2. Loosen the two (2) screw holding the latch hook to the
allowed by the latch hook should be less than 0.5 mm.
The horizontal position of the latch hook should be placed
where the latch head has pushed the plungers of the
monitor switch with the door closed. The vertical position
of the latch hook should be placed where the latch head
has pushed the plungers of the monitored latch switch
and stop switch with the door closed.
5. Make sure all of the switches operate. If the latch head
door closed, adjust the latch hook position.
At that time, the latch head should have pushed the
plungers of the monitored latch switch and stop switch. If
the latch head has not pushed the plungers of the
monitored latch switch and stop switch with door closed,
loose the two (2) screws holding latch hook to the oven
cavity front flange and adjust the latch hook position.
1. In and out play of door remains less than 0.5 mm when
and pulling upper portion of door toward the oven face.
Then check the lower latch hook position, pushing and
pulling lower portion of door toward the oven face. Both
results (plays of the door) should be less than 0.5mm.
2. Remove the fan duct from the oven cavity, referring to
at the oven cavity left wall.