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• Microwave power output measurement is made with

the microwave oven supplied at its rated voltage and
operated at its maximum microwave power setting with
a load of (1000 ± 5)g potable water.

• The water is contained in a cylindrical borosilicate

glass vessel having a maximum material thickness of
3 mm and an outside diameter of approximately 190
mm.

• The oven and the empty vessel are at ambient

temperature prior to the start of the test.

• The initial temperature (±1) of the water is (10±2)°C. It

is measured immediately before the water is added to
the vessel. After addition of the water to the vessel, the
load is immediately placed on the center of the shelf
which is in the lowest position and the microwave
power switched on.

• The time T for the temperature of the water to rise by a

value 

∆

T of (10±2)°K is measured, where T is the time

in seconds and 

∆

T is the temperature rise. The initial

and final water temperatures are selected so that the
maximum difference between the final water
temperature and the ambient temperature is 5°K.

1) Disconnect power supply cord from the outlet.
2) Remove the screws from the rear and side section. 

The out case must be moved backward to the lifted off.

1) Remove the out case.
2) Disconnect two terminals from the noise filter assy

and remove one screw of the earth terminal.

CAUTION: DISCHARGE HIGH VOLTAGE

CAPACITOR BEFORE SERVICING
(refer to page 5)

1) Disconnect the leadwire from the PCB SUB ASM.

2) Remove the screws for the earth and securing  the

control panel.

3) Lift control panel assembly from the oven by the tab

unhooked.

• The microwave power output P in watts is calculated

from the following formula:

P =

is measured while the microwave generator is
operating at full power. Magnetron filament heat-up
time is not included.

• The water is stirred, to equalize temperature

throughout the vessel, prior to measuring the final
water temperature.

• Stirring devices and measuring instruments are

selected in order to minimize addition or removal of
heat.

4) Remove three screws securing the PCB SUB ASM

from the control panel.

5) Remove the digitron window.

NOTE : Remove the leadwire and connector VERY

CAREFULLY. Be sure to grasp the connector
and not the wires.

5-3

Water Load

Turn Table

4187 X (

∆

T) + 0.88 X (T

2 

- T

0

) X M

T

• T

2

: Temperature after heating

• T

0

: Temperature of bowl

• M: Weight of bowl

1) Open the door.

2) Remove the choke cover cap very carefully with a flat-

blade screwdriver.

3) Lift up and push the door.

1. After replacing the door, be sure to check that the

primary switch, monitor switch, and secondary switch
operate normally.

2. After replacing the door, check for microwave energy

leakage with a survey meter. Microwave energy must be
below the limit of 4 mW/cm

2

. (with a 275 ml water load)

3. When mounting the door assembly to the oven

assembly, be sure to adjust the door assembly parallel to
the chassis. Also adjust so the door has no play between
the inner door surface and oven frame assembly. If the
door assembly is not mounted properly, microwaves may
leak from the clearance between the door and the oven.

5-4

Door seal plate

Remove the choke cover cap

Remove door

1) Disconnect the leadwire from high voltage

transformer and high voltage capacitor.

2) Carefully remove the mounting screws holding the

magnetron and the waveguide.

3) Remove the magnetron assembly until the tube is

clear from the waveguide.

1. When removing the magnetron, make sure its dome

does not hit any adjacent parts, or it may be
damaged.

2. When replacing the magnetron, be sure to install the

magnetron gasket in the correct position and be sure
that the gasket is in good condition.

3. After replacing the magnetron, check for microwave

energy leakage with a survey meter around the
magnetron. Microwave energy must be below the limit
of 5mW/cm

2

. (With a 275 ml. water load).

Make sure that gasket is rigidly attached to the
magnetron. To prevent microwave leakage, tighten
the mounting screws properly making sure there is no
gap between the waveguide and the magnetron.

5-5

Wave Guide

Magnetron

Noise Filter Ass'y

Fan Motor

Guide Suction

H.V Capacitor

H.V.C Bracket

H.V Diode

C. Protector

Air Duct

Oven Lamp

1 ) Disconnect lead wires from the noise filter ass'y and

remove screw securing the noise filter earth wire to
the back plate.

2) Push two hook of the guide suction and lift up the rear

of noise filter ass'y.

3) Disconnect lead wires from H.V. capacitor and

remove screw securing the H.V. diode earth wire to
the back plate.

4) Disconnect each lead wires from the AC relay and the

fan motor.

5) Remove two screws securing the guide suction ass'y

to the back plate and lift up the guide suction ass'y.

6) Remove one screw from H.V. capacitor bracket.

7) Pull H.V. capacitor bracket from the guide suction.

8) Remove the fan from the fan motor.

9) Remove two screws securing the fan motor to the 

guide suction and lift it up.

1) Disconnect the wire leads from oven lamp.

2) Remove one screw securing the Air Duct to the

magnetron.

3) Push hook to Right and Left of Air Duct, with Drive.

4) Lift the oven Lamp up.

1) Disconnect the wire leads from the transformer to the

magnetron, C. Protector ASS'Y assembly.

2) Remove four screws securing the H.V. transformer to

the base plate.

3) Lift the H.V. transformer up.

1) Remove the two screws securing the cover assembly

to the oven cavity.

2) Disconnect the leadwire from the circulation motor

terminal and the sheath heater.

3) Remove the screws of the thermistor, guide assy-

chamber and lift up the guide assy-chamber.

4) Remove a hex nut securing the circulation fan to shaft

of the C-motor.

5) Remove screws securing the motor bracket to the

guide assy-chamber.

6) Remove two hex nuts securing the C-motor to the

motor bracket.

5-6

H.V. Transformer