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

cavity back plate 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.

Power Supply
Cord

Oven Cavity
Back Plate

Square
Hole

Moulding
Cord Stopper

Insert the moulding cord stopper of power supply cord into 
the square hole of the rear cabinet, referring to the Figure 
C-3 (b).

Power Supply

Cord

Oven Cavity

Back Plate

Screw

Green/Yellow

Wire

Brown Wire

Blue
Wire

Fuse Holder Assembly

TH

W

DE

R

L

N

1.

CARRY OUT  3D  CHECKS.

Disconnect the leads from the control unit.

Remove the one (1) screw holding the control panel to the 
front panel of the oven cavity.

1.

2.

3.

Lift up the control panel assembly and release it from the 
oven cavity.

Now, the control panel assembly is free.

4.

5.

CARRY OUT  3D  CHECKS.

Remove the control panel assembly, referring to chapter of 
CONTROL PANEL ASSEMBLY REMOVAL.

Disconnect the ribbon cable of the membrane switch from 
the connector (CN-G) on the control unit.

Tear away the graphic sheet from the control panel frame.

Tear away the membrane switch from the control panel 
frame.

Remove remaining adhesive on the control panel frame sur-
faces with a soft cloth soaked in alcohol.

Tear the backing paper from the new membrane switch.

Insert the ribbon cable of the membrane switch into the slit 
of the control panel frame.

Adjust the upper edge and right edge of the membrane 
switch to the small depression on the surface of the control 
panel frame.

Attach the membrane switch to the control panel frame by 
rubbing with a soft cloth not to scratch.

Tear the backing paper from the new graphic sheet.

Adjust the upper edge and right edge of the graphic sheet 
to the large depression on the surface of the control panel 
frame.

Attach the graphic sheet to the control panel frame by rub-
bing with a soft cloth not to scratch.

Connect the ribbon cable of the membrane switch to the 
connector (CN-G) on the control unit.

1.

2.

3.

4.

5.

1.

2.

3.

4.

5.

6.

7.

8.

9.

NOTE: Do not contact the contact surface of the ribbon 

cable (edge) and the rubber connector directly with 
your fingers. This is to avoid oxidized. If display digits 
are missing or scrambled, remove control unit and  
clean contact surface with alcohol. After cleaning, 
do not attach the rubber connector until alcohol 
dries up. Do not use alcohol or solution to clean the 
rubber connector. Make sure that there is no trash 
or foreign substance on contact surface of the rubber 
connector.

Graphic sheet

Ribbon

cable

Connector

(CN-G)

Small depression

Control panel frame

Slit

Control unit

Membrane

switch

Ribbon

cable

Large

depression

R-291(K)M

10 - 4

CARRY OUT  3D  CHECKS.

Remove the control panel assembly, referring to section of 
CONTROL PANEL ASSEMBLY REMOVAL.

Disconnect wire leads from the switches.

Remove two (2) screws holding latch hook to oven flange.

Remove latch hook assembly from oven flange.

Push outward on the two (2) retaining tabs holding switch in 
place.

Switch is now free.

1.

2.

3.

4.

5.

6.

7.

Re-install each switch in its place. The 1st. latch switch and 
the monitor switch are in the lower position and the 2nd. in -
terlock relay control switch is in the upper position

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

Re-connect wire leads to each switch. Refer to pictorial diagram.

Reinstall the control panel assembly to the oven cavity.

Reconnect wire leads to the control unit, referring to the pic-
torial diagram. 

Make sure that the monitor switch is operating properly and 
check continuity of the monitor circuit. Refer to chapter "Test 
Procedure" and Adjustment procedure.

1.

2.

3.

4.

5.

6.

CARRY OUT  3D  CHECKS.

If  the 1st. latch switch, 2nd. interlock relay control switch and 
monitor switch do not operate properly due to a misadjust -
ment, 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 with washers 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.

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.       

1.

1.

Then check lower portion of the 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.

When the door is open, the contacts of the 1st. latch switch 
and 2nd. interlock relay control switch open within 1.6mm 
gap between right side of cavity face and the door.

Monitor switch contacts close when door is opened.

Re-install outer case and check for microwave leakage 
around door with an approved microwave survey meter. 
(Refer to Microwave Measurement Procedure.)

Latch Heads

Latch Hook

Door

Door Sensing Switch

Secondary Interlock Switch

Monitor Switch

2.

3.

4.

Disconnect the power supply cord.

Open the door slightly.

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.

Pry the choke cover by inserting a putty knife as shown Figure C-6.

Release choke cover from door panel.

Now choke cover is free.

NOTE: When carrying out any repair to the door, do not 

bend or warp the slit choke (tabs on the door panel 
assembly) to prevent microwave leakage.

1.

2.

3.

4.

5.

6.

Choke Cover

Door Frame

Putty Knife

R-291(K)M

10 - 5

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

per and lower oven hinges by lifting up.

8.   Now, door panel with door frame is free from oven cavity.

9.   Release door panel from ten (10) tabs of door frame and re-

move the door frame by sliding the door panel downward.

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 the two (2) screw holding the door handle and the 

glass stopper to the door frame.

16. Remove the door handle and the glass stopper from the 

door frame.

17. Remove the door glass from the door frame by sliding the 

door glass rightwards.

18. Now, door glass is free.

1.  Insert door glass into the door frame by sliding leftwards.

2.  Re-install the glass stopper and the door handle to the door 

frame with the two (2) screws.

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 ten (10) tabs of 

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

5.  Put sealer film on door panel. Refer to “Sealer Film” about 

how to handle new one.

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;

1)   Make sure that 1st. latch switch, 2nd. interlock relay 

control switch and monitor switch are operating prop -
erly. (Refer to chapter “Test Procedures”.)

2)   An approved microwave survey meter should be used 

to assure compliance with proper microwave radiation 
emission limitation standards.

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 mi-
crowave energy from oven cavity during cook cycle. 
This function does not require that door be air-tight, 
moisture (condensation)-tight or light-tight. There -
fore, occasional appearance of moisture, light or 
sensing of gentle warm air movement around oven 
door is not abnormal and do not of themselves, 
indicate a leakage of microwave energy from oven 
cavity.

Upper Oven
Hinge

Lower
Oven Hinge

Pin

Upper
Oven Hinge

Slit choke of
door panel

Choke Cover

Pin

Lower Oven

Hinge

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.

Sealer film

Backing film

Adhesive tape

Figure C-8. Sealer  lm

R-291(K)M

10 - 6

R-291(K)M

11 – 1

R218L(W)

After adjustment of door latch switches, monitor switch and door are completed individually or collectively, the following leakage test must be per-

microwave oven.

The safety switch must prevent microwave radiation emission in excess of 5mW/cm

2

 at any point 5cm or more from external surface of the oven.

Before beginning the actual test for leakage, proceed as follows;

Important:

Survey instruments that comply with the requirement for instrumentations as prescribed by the performance standard for microwav e ovens must
be used for testing.

Recommended instruments are:

NARDA 8100

NARDA 8200

HOLADAY HI 1500

SIMPSON 380M

2. Place the oven tray into the oven cavity.

3. Place the load of 275  15ml of water initially at 20  5 C in the centre of the oven tray. The water  container should be a low form of 600 ml beaker

with inside diameter of approx. 8.5cm and made of an electrically non-conductive material  such as glass or plastic.

The placing of this standard load in the oven is important not only to protect the oven, but also to insure that any leakage is  measured accurately.

4. Close the door and turn the oven ON with the timer set for several minutes. If the water begins to boil before the survey is  completed, replace it

with 275ml of cool water.

5. Move the probe slowly (not faster that 2.5cm/sec.) along the gap.

6. The microwave radiation emission should be  measured at any point of 5cm or more from the external surface of the oven.

                                                                                      Microwave leakage measurement at 5 cm dis tance

mW cm

2

mW cm

2

Microwave leakage measurement at 5 cm distance