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R-874M - 27

1. CARRY OUT 3D CHECKS.
2. Remove the wire leads as Positive lock

®

 connector

removal above.

3. Lift up the oven lamp from its retaining clips.
4. Now, the oven lamp is free.

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

wire to the cavity back plate.

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

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

4. Release the power supply cord from the rear cabinet.
5. Now, the power supply cord is free.

1. Insert the moulding cord stopper of power supply cord

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

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

1. CARRY OUT 3D CHECKS.
2. Remove the two (2) screws holding the two (2) termi-

nals of the main wire harness to the top heating
element.

3. Remove the two (2) screws holding the two (2) grill

heater angles to the top of the oven cavity.

4. Remove the two (2) grill heater angles from the oven

cavity.

5. Remove the top heating element from the top of the

oven cavity.

6. Now the top heating element is free.

1. CARRY OUT 3D CHECKS.
2. Push the lever of positive lock

®

 connector.

3. Pull down on the positive lock

®

 connector.

CAUTION: WHEN YOU (SERVICE ENGNEERS) CON-

NECT THE POSITIVE LOCK

®

 CONNEC-

TORS TO THE TERMINALS, CONNECT
THE POSITIVE LOCK

®

 SO THAT THE LE-

VER FACES YOU (SERVICE ENGNEERS).

BULB

LOCK

Terminal

Push

Pull down

1

2

Lever

Positive lock®

connector

1. CARRY OUT 3D CHECKS.
2. Remove the turntable motor cover from the base plate,

referring to "TURNTABLE MOTOR REPLACEMENT".

3. Disconnect the wire leads from the bottom heating

element.

POWER
SUPPLY CORD

MOULDING
CORD STOPPER

OVEN CAVITY
BACK PLATE

SQUARE HOLE

Power supply cord

Green/ Yellow
wire

Brown wire

Oven cavity back plate 

Blue wire

Noise filter

Screw

L

TP

  F2 F 8 A

TL

RED

F1 20 A

WHT

N

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R-874M - 28

4. Remove the two (2) nuts holding the bottom heating

element to the oven cavity.

5. Remove the heater cover and the heater packing from

the bottom heating element.

6. Remove the bottom heating element from the oven

cavity .

1. CARRY OUT 3D CHECKS.
2. Remove the control panel assembly referring to "CON-

TROL PANEL ASSEMBLY REMOVAL".

3. Remove the open lever from the oven cavity front plate

by removing the control panel assembly.

4. Disconnect the leads from all switches.
5. Remove the two (2) screws holding the latch hook to

the oven cavity.

6. Remove the latch hook.
7. Remove the switch(es) from the latch hook by pushing

the retaining tab backwards slightly and turning the
switch(es) on the post.

8. Now the switch(es) is free.

If the monitored latch switch, stop switch and monitor
switch do not operate properly due to a mis-adjustment,
the following adjustment should be made.
1. CARRY OUT 3D CHECKS.
2. Loosen the two (2) screws holding the latch hook to

the oven cavity front flange.

3. With the door closed, adjust the latch hook by moving

it back and forward or up and down. In and out play of
the door allowed by the latch hook should be less than
0.5 mm. The horizontal position of the latch hook
should be placed where the monitor switch has acti-
vated with the door closed. The vertical position of the
latch hook should be placed where the monitored latch
switch and stop switch have activated with the door
closed.

4. Secure the screws with washers firmly.
5. Make sure of the all switches operation. If the latch

head has not pushed the plungers of the monitor
switch with door closed, adjust the latch hook position.
At that time, the latch head should have pushed the
plungers of the monitored latch switch and stop switch.
If the latch head has not pushed the plungers of the
monitored latch switch and stop switch with door
closed, loose two (2) screws holding latch hook to
oven cavity front flange and adjust the latch hook
position.

1. In and out play of door remains less than 0.5 mm when

latched position. First check the latch hook position,
pushing and pulling upper portion of the door toward

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

2. The stop switch  interrupt the circuit before the door

can be opened.

3. When the door is opened the contacts (COM-NC) of

the monitor switch and monitored latch switch close.
And the contacts (COM-NO) of their switches open.

4. When the door is closed the contacts (COM-NC) of the

monitor switch and monitored latch switch open. And
the contacts (COM-NO) of their switches close.

5. Re-install outer case and check for microwave leakage

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

MONITOR SWITCH

STOP SWITCH

MONITORED
LATCH SWITCH

Tab

Post

Post

Post

Tab

Tab

DOOR

LATCH HOOK

MONITOR SWITCH

MONITORED
LATCH SWITCH

 STOP SWITCH

OPEN LEVER

LATCH
HEADS

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R-874M - 29

1. Disconnect the oven from the power supply.
2. Push the open button and open the door slightly.
3. Insert an putty knife (thickness of about 0.5mm) into the

gap between the choke cover and door frame as shown
in Figure C-7 to free engaging parts.

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

6. Lift the door upwards.
7. Now, door sub assembly is free from oven cavity.
8. Remove the four (4) screws holding the door panel to

the door frame.

9. Release door panel from six (6) tabs of door frame by

sliding door panel upward.

10.Now, door panel is free.
11.Slide latch head upward and remove it from door

frame with releasing latch spring from door frame and
latch head.

12.Now, latch head and latch spring are free.
13.Remove the two (2) screws holding the glass stopper to

the door frame.

14.Remove the glass stopper from the door frame.
15.Slide the front door glass leftwards and then slide

upwards to release the tabs holding it.

16.Now, the front door glass is free

RE-INSTALL
1. Re-install the front door glass to the door frame as

follows.
a) Insert the upper edge of the front door glass into the

six (6) tabs of the door frame.

b) Slide the front door glass downwards and insert the

lower edge of the front door glass into the six (6) tabs
of the door frame.

c) Slide the front door glass rightwards and insert the

right edge of the front door glass into the one (1) tab
of the door frame.

2. Re-install the glass stopper to the door frame as follows.

a) Re-install the glass stopper to the door frame so that

the two (2) holes of the glass stopper meet the two
(2) pins of the door frame.

b) Hold the glass stopper to the door frame with the two

(2) screws.

3. Re-install the latch spring to the latch head. Re-install

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

4. Re-install door panel to door frame by fitting six (6) tabs

of door frame to six (6) holes of door panel.

5. Hold the door panel to the door frame with four (4)

screws.

6. Locate door panel hinge pins into cavity hinge location

holes.

7. Re-install choke cover  to door panel by clipping into

position.

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 centre 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.

PIN

PIN

LOWER
OVEN HINGE

UPPER
OVEN HINGE

LOWER
OVEN HINGE

CHOKE COVER

DOOR
PANEL

DOOR SUB 
ASSEMBLY

SLIT CHOKE

10

5

4

12

8

7

9

11

3

2

1

Choke Cover

Door Frame

Putty Knife

6

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R-874M - 30

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 standard whose accu-
racy  can be traced to National Physical Laboratory
Standards.

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 detec-
tor.

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