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R-24STM - 17

1. CARRY OUT 3D CHECKS.

2. Disconnect the wire leads from the switches and control

panel.

3. Remove the control panel assembly from the oven

cavity front flange. Referring to chapter "CONTROL
PANEL ASSEMBLY REMOVAL".

4. Remove the two (2) screw holding the latch hook to the

oven flange.

5. Remove the latch hook assembly from the oven flange.
6. To remove the switch.
6-1. With pushing outward on the tab that is holding the

switch, turn the switch so that the post is an axis.

6-2. Pull out the switch from the latch hook. Do not break the

post or tab of the latch hook.

6-3. Now the switch is free.

Re-install
1. Re-install each switch in its place. The monitored latch

switch is in the lower position and the monitor switch is
in the middle position. The stop switch is in the upper
position.

2. Re-connect wire leads to each switch. Refer to chapter

“Pictorial Diagram”.

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

oven flange.

4. Re-install the control panel assembly to the oven cavity

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

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

front flange.

5. Re-connect wire leads to the control unit. Refer to

chapter “Pictorial Diagram”.

6. Make sure that monitor switch is operating properly

and check continuity of the monitor circuit. Refer to
chapter “Test Procedure”, and Adjustment Procedure
below.

1. CARRY OUT 3D CHECKS.
     If the monitored latch switch, stop 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 the latch hook to the

flange of the oven front face.

3. With the 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 horizontal position
of the latch hook should be adjusted so that the monitor
switch is activated with the door closed. The vertical
position of the latch hook should be adjusted so that the
stop switch and the monitored latch switch are activated
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, make sure of the following.
1. In and out play of the 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
latch hook,  pushing and pulling lower portion of door
toward the oven face. Both results (play in the door)
should be less than 0.5mm.

2. The monitored latch switch and stop switch interrupt the

circuit before the door can be opened.

3. The monitor switch contacts (COM-NC) close when the

door is opened.

Latch hook

Tab

SW3: Stop switch 

SW2: Monitor switch 

SW1:  Monitored latch switch 

Tab

Tab

Latch hook

SW3: Stop switch

Door

SW2: Monitor switch

SW1:Monitored latch switch

Latch heads

R-24STM - 18

10

5

4

12

8

7

9

11

3

2

1

Choke Cover

Door Frame

Putty Knife

6

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
Microwave 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 the
door be air-tight, moisture (condensation)-tight
or light-tight. Therefore, occasional appearance
of moisture, light or sensing of gentle warm air
movement around oven door is not abnormal
and does not indicate a leakage of microwave
energy from oven cavity.

INNER SEALER FILM
Installation
1. Tear away the backing film.
3. Put the pasted side of the inner sealer film on the door

panel.

REMOVAL
1. Disconnect the power supply cord.
2. Open the door slightly.
3. Remove the choke cover taking care not to break clips

by inserting an  iron plate (thickness of about 0.5mm) or
flat type screw driver to the gap between the choke cover
and door panel as shown Figure C-4 to free the engaged
parts.

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

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

upper and lower oven hinges by lifting up.

7. 1. Remove door assy by removing screws (4).
8. Release door panel from tabs of door frame and remove

door frame by sliding the door panel downward.

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

with releasing latch spring from door frame and latch
head.

13.Now, latch head and latch spring are free.
14.Remove Glass Stopper Screw (noting position of

15.Slide glass towards Glass Stopper position and then

16. Lift upper edge of glass, which will now be free from

17.Refitting is a reversal of the above when refitting,

RE-INSTALL
1. Re-install the outer door glass to the door frame with the

glass stopper.

2. Hold the glass stopper with the one (1) screw.
3. Re-install latch spring to the head. Re-install latch spring

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

4. Re-install door panel to door frame by fitting tabs of door

frame to holes of door panel.

5. Put sealer film on door panel. Refer to “Inner Sealer

Film” and figure C-6, on how to handle the new film.

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

and lower oven hinges.

7. Re-install choke cover  to door panel by pushing.
Note: After any service to the door;
(A) Make sure that monitored latch switch, stop switch

Door film

Finger tab

Backing film

PIN

PIN

LOWER
OVEN HINGE

UPPER
OVEN HINGE

LOWER
OVEN HINGE

CHOKE COVER

DOOR
PANEL

DOOR SUB 
ASSEMBLY

SLIT CHOKE

R-24STM - 19

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 275ml is 50 W/m

 (equivalent to

5mW/cm

) at a distance of 5cm from the oven.

The following items are required to carry out this test:-
1.

A low form of 600ml beaker made from

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

±

15ml 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 Standards.

Recommended instruments are:

Apollo "XI"
Celtec "A1000"

Before commencing the test, check 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.

Dotted line indicates the path taken by the leakage detector.

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
the 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 2.5cm/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

R-24STM - 20

Parts

Symbol

Value / Data

Fuse

F1

F8A 250V

Thermal cut-out (OVEN)

TC2

125

°C

Oven lamp

OL

240-250V 25W

High voltage capacitor

C

0.88

µ AC 2100V

Magnetron

MG

Filament < 1

Ω

Filament – chassis 

∞ ohm.

Power transformer

T

Filament winding < 1

Ω

Secondary winding Approx. 140

Ω

Primary winding Approx. 2.3

Ω

WARNING: WIRING / RE-WIRING.
Before carrying out any work; carry out 3D checks.
1. Disconnect the supply
2. Open the door and wedge open.
3. Discharge the high voltage capacitor.

RE-WIRING.
Ensure the following:
1. Wires must not touch:

a) High voltage parts.

(Magnetron, high voltage transformer, high
voltage capacitor and high voltage rectifier).

b) Parts that become hot.

(Heating elements, oven lamp, oven cavity
magnetron and high voltage transformer).

c) Sharp edges.

(Bottom plates, oven cavity, waveguide
flange, chassis support and other
metallic parts).

d) Movable parts.

( Fan blade, and motor and switches.

2. Positive lock connectors are fitted correctly.  Ensure

the locking pin is located correctly.

3. Wires are connected correctly as per pictorial

diagram.

4. No wire leads are trapped by the outer wrap.