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19

Gap

Rotor

Bracket

Stator

Groove joint pliers

Coil

Shaft

Axis

Stator

Rotor

These are the positions 
that should be pinched 
with pliers.

Shaft

Table

Center of
bracket

1. CARRY OUT 3D CHECKS.
2. Remove the single (1) screw holding the green/yellow

wire to the oven cavity.

3. Disconnect the leads of the power supply cord from the

noise filter, referring to the Figure C-4 (a).

4. Release the moulding cord stopper of the power supply

cord from the square hole of the oven cavity back plate,
referring to the Figure C-4 (b).

5. Now, the power supply cord is free.

1. Insert the moulding cord stopper of power supply cord

into the square hole of the rear cabinet, referring to the
Figure C-4 (b).

2. Install the earth wire lead of power supply cord and the

earth angle to the oven cavity with one (1) screw and
tight the screw.

3. Connect the brown and blue wire leads of power supply

cord to the noise filter correctly, referring to the Pictorial
Diagram.

6. Release the fan motor assembly from the oven cavity.
7. Remove the fan blade from the fan motor shaft accord-

ing to the following procedure.

8. Hold the edge of the rotor of the fan motor by using a

pair of groove joint pliers.

9. Remove the fan blade assembly from the shaft of the

fan motor by pulling and rotating the fan blade with your
hand.

10.Now, the fan blade will be free.

11.Remove the two (2) screws holding the fan motor to the

fan duct.

12.Now, the fan motor is free.

1. Install the fan motor to the fan duct with the two (2)

screws.

2. Install the fan blade to the fan motor shaft according to

the following procedure.

3. Hold the center of the bracket which supports the shaft

of the fan motor on the flat table.

4. Apply the screw lock tight into the hole (for shaft) of the

fan blade.

5. Install the fan blade to the shaft of fan motor by pushing

the fan blade with a small, light weight, ball peen
hammer or rubber mallet.

6. Install the fan motor assembly to the oven cavity with

three (3) screws.

7. Install the magnetron with three (3) screws.
8. Re-install the wire leads to the hole of the fan duct.
9. Connect the wire leads to the magnetron and the fan

motor, referring to the pictorial diagram.

Power Supply Cord

Oven Cavity 
Back Plate

Screw

Green/Yelow
Wire

Brown Wire

Fuse

Blue Wire

Noise Filter

Power Supply 
Cord

Oven Cavity 
Back Plate

Square 
Hole

Moulding
Cord Stopper

20

latch hook, pushing and pulling lower portion of the
door toward the oven face. Both results (play in the
door) should be less than 0.5mm.

2. The 1st. latch switch, 2nd. interlock relay control switch

interrupt the circuit before the door can be opened.

3. Monitor switch contacts close when door is opened.
4. Re-install outer case and check for microwave leakage

around door with an approved microwave survey meter.
(Refer to Microwave Measurement Procedure.)

1. CARRY OUT 3D CHECKS.
If the 1st. latch switch, 2nd. interlock relay control switch
and monitor switch do not operate properly due to a
misadjustment, the following adjustment should be made.
2. Loosen the two (2) screws holding latch hook to the

oven cavity front flange.

3. With door closed, adjust latch hook by moving it back

and forth, and up and down. In and out play of the door
allowed by the upper and lower position of the latch
hook should be less than 0.5mm. The vertical position
of the latch hook should be adjusted so that the 1st.
latch switch and 2nd. interlock relay control switch are
activated with the door closed. The horizontal position
of the latch hook should be adjusted so that the plunger
of the monitor switch is pressed with the door closed.

4. Secure the screws firmly.
5. Check the operation of all switches. If each switch has

not activated with the door closed, loosen screw and
adjust the latch hook position.

After adjustment, check the following.
1. In and out play of door remains less than 0.5mm when

in the latched position. First check upper position of
latch hook, pushing and pulling upper portion of door
toward the oven face. Then check lower portion of the

1. CARRY OUT 3D CHECKS.
2. Disconnect wire leads from the switches.
3. Remove two (2) screws holding latch hook to oven

flange.

4. Remove the switch lever from the oven cavity
5. Remove latch hook assembly from oven flange.
6. Push outward on the two (2) retaining tabs holding

switch in place.

7. Switch is now free.
Re-install
1. Re-install each switch in its place. The 1st. latch switch

and monitor switch are in the lower position and the
2nd. interlock relay control switch is in the upper
position.

2. Re-connect wire leads to each switch.

Refer to pictorial diagram.

3. Secure latch hook (with two (2) mounting screws) to

oven flange.

4. Install the switch lever to the oven cavity
5. Make sure that the monitor switch is operating properly

and check continuity of the monitor circuit. Refer to
chapter "Test Procedure" and Adjustment procedure.

REMOVAL
1. Disconnect the oven from the power supply.
2. Open the door slightly.
3. Insert a putty knife (thickness of about 0.5mm) into the

gap between the choke cover and corner portion of
door panel as shown in Figure C-6 to free engaging
parts.

4. Pry the choke cover by inserting a putty knife in order

shown in figure C-6.

5. Release choke cover  from door panel.
6. Now choke cover is free.

7. Release two (2) pins of door panel from two (2) holes

of upper and lower oven hinges by lifting up.

8. Now, door panel is free from oven cavity.
9. Release door panel from ten (10) tabs of door frame

and remove door frame by sliding the door panel
downward.

Latch Heads

Latch Hook

Door

2nd. Interlock Relay
Control Switch

Monitor Switch

Switch Lever

1st. Latch Switch

10

5

4

8

7

9

11

3

2

1

Choke Cover

Door Frame

Putty Knife

6

21

Sealer film

Backing film

Adhesive tape

10.Now, door panel with sealer film is free.
11.Tear sealer film from door panel.
12.Now, door panel is free.
13.Slide latch head upward and remove it from door frame

with releasing latch spring from door frame and latch
head.

14.Now, latch head and latch spring are free.
15.Remove door screen from door frame.
16.Now, door screen is free.

RE-INSTALL
1. Re-install door screen to door frame.
2. Re-install latch spring to the head. Re-install latch

spring to the door frame. Re-install latch head to the
door frame.

3. Re-install door panel to door frame by fitting ten (10)

tabs of door frame to ten (10) holes of door panel.

4. Put sealer film on door panel. Refer to "Sealer Film" and

figure C-8, on how to handle the new film.

5. Catch two (2) pins of door panel on two (2) hole of upper

and lower oven hinges.

6. Re-install choke cover  to door panel by pushing.
Note: After any service to the door;
(A) Make sure that 1st. latch switch, 2nd. interlock

After any service, make sure of the following :
1. Door latch heads smoothly catch latch hook through

latch holes and that latch head goes through center of
latch hole.

2. Deviation of door alignment from horizontal line of

cavity face plate is to be less than 1.0mm.

3. Door is positioned with its face pressed toward cavity

face plate.

4. Check for microwave leakage around door with an

approved microwave survey meter.  (Refer to Micro-
wave Measurement Procedure.)

Note:

The door on a microwave oven is designed to act
as an electronic seal preventing the leakage of
microwave energy from oven cavity during cook
cycle. This function does not require that door be
air-tight, moisture (condensation)-tight or light-
tight. Therefore, occasional appearance of mois-
ture, light or sensing of gentle warm air movement

around oven door is not abnormal and do not of
themselves, indicate a leakage of microwave en-
ergy from oven cavity.

Installation
1. Put the adhesive tape on the backing film of the sealer

film as shown in Fig. C-8.

2. Tear the backing film by pulling the adhesive tape.
3. Put the pasted side of the sealer film on the door panel

Pin

Pin

Upper Oven Hinge

Lower 
Oven
Hinge

Lower Oven
Hinge

Choke Cover

Slit Choke

Door
Panel

22

After any repair, the microwave oven must be checked for
microwave leakage to ensure continued safe operation.
BS EN 60335-2-25 specifies that the maximum permitted
leakage with a load of 275 ml is 50 W/m

2 

(equivalent to 5

mW/cm

2

)

 

at  a distance of 5 cm from the oven.

The following items are required to carry out this test:-
1.  A low form of 600 ml beaker made from an electrically

non-conductive material, such as glass or plastic, with
an inside diameter of approximately 8.5 cm. This must
contain 275 

± 15 ml of water, at an initial temperature

of 20 

± 2˚C.

2. A leakage detector which has been calibrated within

the preceding 12 months to a stand whose accuracy
can be traced to National Physical Laboratory Stand-
ards.

Recommended instruments are:

Apollo "XI"
Celtec "A100"

Before commencing the test, check that the leakage
detector is functioning and adjusted according to the
manufacturer's instructions, and any spacers are fitted to
ensure that measurement is taken 5cm from the surface of
the oven.

1. Place the beaker containing the water load in the oven

cavity at the centre of the turntable. The placing of this
standard load in the oven is important, not only to
protect the oven, but also to ensure that any leakage it
is not disguised by too large a load absorbing energy.

2. Close the oven door, and with the power level set to

FULL, turn the oven ON with the timer set for a few
minutes operation. Should the water begin to boil
before the test has been completed, it should be
replaced.

3. As shown in the diagram below, move the probe slowly

(not faster than 2.5 cm/sec.);-

a) around the edge of the door following the gap
b) across the face of the door
c) across any vents in the oven's sides, rear or top

Dotted line indicates the path taken by the leakage detector.