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27

1.

CARRY OUT 3D CHECKS

2.

Release the cord bushing from the rear cabinet.

3.

Disconnect the brown and blue wires of the power
supply cord from the noise filter.

4.

Loosen the single (1) screw holding the earth angle
and earth wire of power supply cord.

5.

Remove the power supply cord.

CAUTION: DO NOT ALLOW THE WIRE LEADS OF

THE POWER SUPPLY CORD TO COME
NEAR THE HIGH VOLTAGE TRANS-
FORMER. BECAUSE THE HIGH VOLT-
AGE TRANSFORMER BECOMES HOT.

Re-install
1.

Insert the power supply cord into the cord bushing.

2.

Connect the brown and blue wires of power supply
cord into the terminals of noise filter, referring to
pictorial diagram.

3.

Insert the green/yellow wire of power supply cord
into the earth angle, and tight the screw holding the
earth angle.

4.

Re-install the cord bushing to the rear cabinet.

5.

Re-install the rear cabinet to oven cavity and the
bottom plate with the eleven (11) screws and two (2)
washers.

6.

CARRY OUT 4R CHECKS.

N

Screw

Green/Yellow 
wire

Cord
bushing

Rear 
cabinet

Power
supply 
cord

Blue wire

Brown wire

Noise filter unit

L

WHT

BLK

latch hook.

6. For 1st latch and stop switches removal

6-1. Disconnect the wire leads from the 1st latch and

stop switches.

6-2. Remove the single (1) screw and nut holding the

1st latch and stop switches to the latch hook.

CAUTION: WHEN THE 1ST LATCH SWITCH AND

2ND. LATCH SWITCH ARE INSTALLED,
THE TWO (2) TABS OF THE LATCH
HOOK SHOULD BE BROKEN.

1. CARRY OUT 3D CHECKS.
2. Remove the control panel from the oven cavity refer-

ring to “CONTROL PANEL REMOVAL”.

3. Remove the two (2) screws holding the latch hook to

the oven cavity.

4. Open the door and pull the latch hook out of the oven

cavity.

5. For 1st latch, 2nd latch or Monitor switch removal

5-1. Disconnect the wire leads from the switch.
5-2. Push the retaining tabs outward slightly and then

pull the switch forwards and remove it from the

In case 1st latch switch, 2nd latch, stop switch, 3rd latch
switch and monitor switch do not operate properly due to a
mis-adjustment, the following adjustment should be made.

1. Loosen the two (2) screws holding the latch hook.
2. 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
0.5mm. The vertical position of the latch hook should be
placed where the stop switch and 1st, 2nd, 3rd latch
switches have activated with the door closed.
The horizontal position of the latch hook should be
placed where the monitor switch has activated with the
door closed.

3. Secure the screws with washers firmly.
4. Make sure of the 1st, 2nd, 3rd latch switches, stop

switch, and monitor switch operation. If those switches
have not activated with the door closed, loose two (2)
screws holding latch hook and adjust the latch hook
position.

After adjustment, make sure of the following:
1. The stop switch and 1st, 2nd, 3rd latch switches interrupt

the circuit before the door open when the door release
lever is pulled, and then and monitor switch close the

circuit when the door is opened.

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

around the door with an approved microwave survey

meter. (Refer to Microwave Measurement Procedure.)

Latch head

Monitor switch

Latch hook

1st. latch switch

2nd. latch switch

Stop switch

3rd. latch switch

Latch head

Joint lever

Door release
lever

Latch lever

28

1. CARRY OUT 3D CHECKS.
2. Remove four (4) screws holding the upper and lower

oven hinge to the oven cavity.

3. Remove door assembly with upper and lower oven

hinges by pulling it forward.

4. On re-installing new door assembly, secure the upper

and lower oven hinges with the four (4) mounting
screws to the oven cavity. Make sure the door is
parallel with bottom line of the oven face plate and the
latch head pass through the latch holes correctly.

5. CARRY OUT 4R CHECKS.
Note:

After any service to the door, the approved
microwave survey meter should be used to assure
in compliance with proper microwave radiation
standards. (Refer to Microwave Measurement
Procedure.)

When removing and/or loosening hinges such as in door
replacement, the following adjustment criteria are taken.
Door is adjusted to meet the following three conditions by
keeping screws of hinge loose.
1. Adjust door latch heads at a position where they

smoothly catch the latch hook through the latch holes.
Refer to latch switch adjustments.

2. Deviation of the door alignment from horizontal line of

cavity face plate is to be less than 1.0mm.

3. The door is positioned with its face depressed toward

the cavity face plate.

4. Reinstall outer case and check for microwave leakage

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

UPPER
OVEN 
HINGE

LOWER
OVEN 
HINGE

DOOR 
ASSEMBLY

LATCH HEADS

OUTER CASE
CABINET

1. Insert 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 to free the engaging
part. The protect sheet may be used not to damage
the door panel.

2. Lift up the choke cover, now cove is free.

DOOR
PANEL

CHOKE
COVER

FLATE TYPE
SCREW DRIVER

PROTECTION 
BY TAPE

LOWER
OVEN HING

UPPER
OVEN HING

Remove the door assembly, referring to from item 1
through item 3 of “DOOR REPLACEMENT”.
1. Place the door assembly on a soft cloth with facing up.

2. Remove the choke cover, referring to “CHOKE COVER

REMOVAL”.

3. Release the oven hinges from the door panel.
4. Now, the  oven hinges are free.

5. Remove the two (2) screws holding the door handle to

door.

6. Remove the door handle from the door panel.

(UPPER AND LOWER LATCH HEADS REMOVAL)
7. Remove the door release lever from the door assem-

bly.

8. Remove the three (3) screws holding the joint plate to

the door panel.

9. Release the latch spring from the tab of the joint lever

and joint plate.

10.Release the latch heads from joint lever and joint plate.
11.Now, the latch heads are free.

12.Set the four (4) tabs of the door frame upright.
13.Remove the door frame from the door panel. Now,

door frame is free.

14.Remove the four (4) screws holding the two (2) outside

window fixing plates to the door panel.

15.Now, the door glass is free.

29

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.

Whilst the maximum leakage permitted in BS EN 60335-2-25 is 50 W/m

2 

(equivalent to 5 mW/cm

2

), it is not normal to

detect any significant leakage, and therefore any detected leakage should be investigated.

30

SCHEMATIC

NOTE: CONDITION OF OVEN

1. DOOR CLOSED

2.

        APPEARS ON DISPLAY

SCHEMATIC

NOTE: CONDITION OF OVEN

1. DOOR CLOSED.

2. TIME KEY TIUCHED.

3. COOKING TIME PROGRAMMED.

4. START KEY TOUCHED

NOTE: " " INDICATES COMPONENTS WITH POTENTIALS ABOVE 250V.

C1 and C2: 1.07

µ

F/ AC 2100V for R-2397G

C1 and C2: 0.94

µ

F/ AC 2100V for R-2297G

NOISE FILTER

SW1: 
1ST LATCH SWITCH
(PRIMARY INTERLOCK SWITCH)

SW4:

MONITOR

SWITCH

R1:

MONITOR

RESISTOR

TC3:

BLOWER MOTOR

THERMAL CUT OUT

115C°

A7

A5

TC4: 

OVEN THERMAL 

CUT OUT 115C°

F2:

FUSE

F6.3A

SW2: 2ND LATCH SWITCH

A3

TC2: MAGNETRON
        THERMAL CUT OUT
        145C°(LOWER)

OVEN LAMP

BLOWER MOTOR

A1

CONTROL
UNIT

B1

SW3: 
3RD LATCH SWITCH

EXHAUST 

THERMISTER

SW5: STOP SWITCH

TAB3

D3

TAB2

TAB1

TAB4

T1: HIGH VOLTAGE

      TRANSFORMER

ASYMMETRIC
RECTIFIER

 H. V. RECTIFIER

C1: H.V. CAPACITOR

MG1: MAGNETRON (UPPER)

(REAR)

OL

SM

STIRRER MOTOR

SM

BM

RY1

RY3

RY4

TC1: 
MAGNETRON
THERMAL 
CUT OUT
145C°(UPPER)

B2

B3

D1

H1

H3

 INTAKE 

THERMISTER

MAGNETRON

THERMISTER

ASYMMETRIC
RECTIFIER

 H. V. RECTIFIER

C2: H.V. CAPACITOR

MG2: MAGNETRON (LOWER)

T2: HIGH VOLTAGE

      TRANSFORMER

(FRONT)

F1 : FUSE 13A

F4: FUSE M8A(R-2397G)
        / M6.3A(R-2297G)

F3: 
FUSE M8A
(R-2397G)
 / M6.3A
(R-2297G)

230V - 240V~50Hz

F1 : FUSE 13A

NOISE FILTER

SW1: 
1ST LATCH SWITCH
(PRIMARY INTERLOCK SWITCH)

SW4:

MONITOR

SWITCH

R1:

MONITOR

RESISTOR

TC3:

BLOWER MOTOR

THERMAL CUT OUT

115C°

A7

A5

TC4: 

OVEN THERMAL 

CUT OUT 115C°

F2:

FUSE

F6.3A

SW2: 2ND LATCH SWITCH

F4: FUSE M8A(R-2397G)
        / M6.3A(R-2297G)

A3

TC2: MAGNETRON
        THERMAL CUT OUT
        145C°(LOWER)

OVEN LAMP

BLOWER MOTOR

A1

CONTROL
UNIT

B1

SW3: 
3RD LATCH SWITCH

EXHAUST 

THERMISTER

SW5: STOP SWITCH

TAB3

D3

TAB2

TAB1

TAB4

T1: HIGH VOLTAGE

      TRANSFORMER

230V - 240V~50Hz

ASYMMETRIC
RECTIFIER

 H. V. RECTIFIER

C1: H.V. CAPACITOR

MG1: MAGNETRON (UPPER)

(REAR)

F3: 
FUSE M8A
(R-2397G)
 / M6.3A
(R-2297G)

OL

SM

STIRRER MOTOR

SM

BM

RY1

RY3

RY4

TC1: 
MAGNETRON
THERMAL 
CUT OUT
145C°(UPPER)

B2

B3

D1

H1

H3

 INTAKE 

THERMISTER

MAGNETRON

THERMISTER

ASYMMETRIC
RECTIFIER

 H. V. RECTIFIER

C2: H.V. CAPACITOR

MG2: MAGNETRON (LOWER)

T2: HIGH VOLTAGE

      TRANSFORMER

(FRONT)