Component Replacement And Adjustment Procedure - Sharp R-25AM Service Manual

COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE

WARNING: Avoid possible exposure to microwave energy. Please follow the instructions below before
operating the oven.
1. Disconnect the oven from power supply.
2. Make sure that a definite "click" can be heard when the
microwave oven door is unlatched. (Hold the door in a
closed position with one hand, then grip the door
handle and the door lever assembly with the other, this
causes the latch leads to rise, it is then possible to hear
a "click" as the door switches operate.)
3. Visually check the door and cavity face plate for dam-
age (dents, cracks, signs of arcing etc.).
Carry out any remedial work that is necessary before
operating the oven.
Do not operate the oven if any of the following conditions
exist;
Please refer to 'OVEN PARTS, CABINET PARTS, CONTROL PANEL PARTS, DOOR PARTS', when carrying out any
of the following removal procedures:
To prevent an electric shock, take the following
precautions.
1. Before wiring,
1) Disconnect the power supply cord.
2) Open the door and block it open.
3) Discharge the two high voltage capacitors and
wait for 60 seconds.
2. Don't let the wire leads touch to the followiong parts;
1) High voltage parts:
Magnetron, High voltage transformer, High volt-
age capacitor, High voltage rectifier assembly and
High voltage fuse.
2) Hot parts:
Oven lamp, Magnetron, High voltage transformer,
OUTER CASE, REAR CABINET AND POWER SUPPLY CORD REMOVAL
To remove the components, procedure as follows.
1. Disconnect oven from power supply.
2. Open the oven door and wedge it open.
3. Remove the screws from the rear and along side the
edge of the outer case.
4. Slide the case back about 1 inch (3 cm) to free it from
the oven cavity.
5. Lift entire case from the unit.
6. DISCHARGE TWO HIGH VOLTAGE CAPACITORS
BEFORE TOUCHING ANY OVEN COMPONENTS
OR WIRING.
7. Now, outer case is free.
N.B.; Step 1,2 and 9 form the basis of the 3D checks.
CAUTION:DISCHARGE TWO HIGH VOLTAGE CA-
PACITORS BEFORE TOUCHING ANY
OVEN COMPONENTS OR WIRING.
1. CARRY OUT 3D CHECKS.
2. Remove the rear cabinet, too.
3. Disconnect wire lead(s) of high voltage transformer(s)
WARNING FOR WIRING
HIGH VOLTAGE TRANSFORMER(S) REMOVAL
1. Door does not close firmly.
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
and transmission assembly.
7. There is visible damage to the oven.
Do not operate the oven:
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.
and Oven cavity.
3) Sharp edge:
Bottom plate, Oven cavity, Waveguide flange,
Chassis support and other metallic plate.
4) Movable parts (to prevent a fault)
Blower fan blade, Blower fan motor, Switches,
Switch levers, Antenna motors and Sirrer anten-
nas.
3. Do not catch the wire leads in the outer case cabinet.
4. Insert the positive lock connector until its pin is locked
and make sure that the wire leads do not come off
even if the wire leads are pulled.
5. To prevent an error function, connect the wire leads
correctly, referring to the Pictorial Diagram.
To remove rear cabinet and power supply cord:
8. Disconnect the power supply cord from the noise filter.
9. Remove the one (1) screws holding the grounding wire
of power supply cord to the oven cavity.
10.Remove the screws holding the rear cabinet to the
oven cavity and blower motor.
11.Remove the rear cabinet with the power supply cord
from the oven cavity.
12.Loosen the tab of the cord bushing, and remove the
power supply cord with the cord bushing from the rear
cabinet.
13.Remove the cord bushing from the power supply cord,
14.Now, the power supply cord and rear cabinet are free.
from magnetron(s).
4. Remove the wire lead(s) of high voltage transformer(s)
from the wire holder.
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R-25AM