Component Replacement And Adjustment Procedure - Sharp R-937 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 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 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
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
manners.
1. Before wiring,
1) Disconnect the power supply.
2) Open the door and wedge the door open.
3) Discharge the high voltage capacitor and wait for
60 seconds.
2. Don't let the wire leads touch to the following parts;
1) High voltage parts:
Magnetron, High voltage transformer, High volt-
age capacitor and High voltage rectifier assem-
bly.
2) Hot parts:
Grill heating element, Convection heating ele-
To remove the outer case proceed as follows.
1. Disconnect oven from power supply.
2. Open the oven door and wedge it open.
3. Remove the one (1) screw holding the air to the oven
cavity rear plate.
4. Remove the air duct.
5. Remove the nine (9) screws from rear and along the
side edge of case.
6. Slide the entire case back about 3 cm to free it from
retaining clips on the cavity face plate.
(HIGH VOLTAGE CAPACITOR AND HIGH VOLTAGE RECTIFIER ASSEMBLY)
To remove the components, proceed as follows.
1. CARRY OUT 3D CHECKS.
2. Disconnect the filament lead of the high voltage trans-
former and the high voltage wire of the high voltage
transformer from the high voltage capacitor.
3. Disconnect the high voltage wire B from the high
voltage capacitor.
4. Remove one (1) screw holding earth side terminal of
the high voltage rectifier assembly to the base plate
through the capacitor holder.
5. Release the capacitor holder from the base plate.
8. Remove the high voltage capacitor from the capacitor
WARNING FOR WIRING
OUTER CASE REMOVAL
HIGH VOLTAGE COMPONENTS REMOVAL
1. Door does not close firmly.
2. Door hinge, support or latch hook is damaged.
3. The door gasket or seal or 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.
ment, Oven lamp, Magnetron, High voltage trans-
former and Oven cavity.
3) Sharp edge:
Bottom plate, Oven cavity, Weveguide flange,
Chassis support and other metallic plate.
4) Movable parts (to prevent a fault)
Fan blade, Fan motor, Switch, Turntable motor,
Convection motor, convection fan and colling fan.
3. Do not catch the wire leads in the outer case cabinet.
4. Insert the positive lock connector certainly until its pin
is locked. And make sure that the wire leads should
not come off even if the wire leads is pulled.
5. To prevent an error function, connect the wire leads
correctly, referring to the Pictorial Diagram.
7. Lift the entire case from the oven.
8. Discharge the H.V. capacitor before carrying out any
further work.
9. Do not operate the oven with the outer case removed.
N.B.; Step 1, 2 and 8 form the basis of the 3D checks.
CAUTION: DISCHARGE HIGH VOLTAGE CAPACI-
TOR BEFORE TOUCHING ANY OVEN
COMPONENT OR WIRING.
holder.
7. Disconnect the high voltage rectifier assembly from the
high voltage capacitor.
8. Now, the high voltage rectifier assembly and the high
voltage capacitor should be free.
CAUTION: WHEN REPLACING HIGH VOLTAGE
RECTIFIER ASSEMBLY, ENSURE THAT
THE CATHODE (EARTH) CONNECTION
IS SECURELY FIXED TO THE BASE
PLATE THROUGH THE CAPACITOR
HOLDER WITH AN EARTHING SCREW.
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