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[1] Before Servicing
CHAPTER 1. WARNING TO SERVICE PERSONNEL
Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may result in a
severe, possibly fatal, electrical shock.
(Example)
High Voltage Capacitor, High Voltage Power Transformer, Magnetron, High Voltage Recti
fi
er Assembly, High Voltage Harness etc..
Read the Service Manual carefully and follow all instructions.
Don't Touch !
Danger High Voltage
1. Disconnect the power supply cord , and then remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
WARNING:
RISK OF ELECTRIC SHOCK. DISCHARGE THE
HIGH VOLTAGE CAPACITOR BEFORE SERVICING.
The high-voltage capacitor remains charged about 60
seconds after the oven has been switched off. Wait for 60
seconds and then short-circuit the connection of the high-
voltage capacitor (that is the connecting lead of the high-
voltage rectifier) against the chassis with the use of an
insulated screwdriver.
Whenever troubleshooting is performed the power supply must
be disconnected. It may, in some cases, be necessary to con-
nect the power supply after the outer case has been removed,
in this event,
1) Disconnect the power supply cord, and then remove outer case.
2) Open the door and block it open.
3) Discharge high voltage capacitor.
4) Disconnect the leads to the primary of the power transformer.
5) Ensure that the leads remain isolated from other components
and oven chassis by using insulation tape.
6) After that procedure, reconnect the power supply cord.
[2] When the testing is completed
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Reconnect the leads to the primary of the power transformer.
5. Reinstall the outer case (cabinet).
6. Reconnect the power supply cord after the outer case is installed.
7. Run the oven and check all functions.
[3] After repairing
1. Reconnect all leads removed from components during testing.
2. Reinstall the outer case (cabinet).
3. Reconnect the power supply cord after the outer case is installed.
4. Run the oven and check all functions.
Microwave ovens should not be run empty. To test for the pres-
ence of microwave energy within a cavity, place a cup of cold
water on the oven turntable, close the door and set the power
to HIGH and set the microwave timer for two (2) minutes. When
the two minutes has elapsed (timer at zero) carefully check that
the water is now hot. If the water remains cold carry out
Before
Servicing
procedure and re-examine the connections to the
component being tested.
When all service work is completed and the oven is fully as-
sembled, the microwave power output should be checked and
microwave leakage test should be carried out.
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6/26/09 6:30:47 PM
6/26/09 6:30:47 PM
