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14

891M -

After adjustment of door latch switches, monitor switch
and door are completed individually or collectively, the
following leakage test must be performed with a survey
instrument and it must be confirmed that the result meets
the requirements of the performance standard for micro-
wave oven.

REQUIREMENT
The safety switch must prevent microwave radiation emis-
sion in excess of 5mW/cm

2

 at any point 5cm or more from

external surface of the oven.

PREPARATION FOR TESTING:
Before beginning the actual test for leakage, proceed as
follows;
1. Make sure that the test instrument is operating normally

as specified in its instruction booklet.
Important:
Survey instruments that comply with the requirement for
instrumentations as prescribed by the performance
standard for microwave 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.

15

891M -

C1

C3

STOR

THERMI-

BOTTOM HEATER

680K/0.5W

4700p/250V

4700p/250V

10M/0.5W

L

N

0.22 /250V

G-Y/15

/15

/15

FILTER

NOISE

NOISE SUPPRESSION COIL

LIVE

NEUTRAL

H.V. RECTIFIER

RECTIFIER

ASYMMETRIC

 

BRN

BLU

TRANSFORMER

POWER

MAGNETRON

EARTH

CAPACITOR

AC2100V

1.16 F

RY
5

T/C TRANSFORMER

E1

E3

UNIT

CONTROL

B1

B2

E5

E7

A5

A3

A7

RY
6

A1

RY
2

RY
3

RY
4

RY
1

MONITOR

SWITCH

FM

OL

T M

T

CM

WHT
/16

OVEN
THERMAL

CUT-OUT

BLU

/16

WHT

WHT

WHT

GRY

/16

GRY
/18

WHT
/18

WHT

/18

BLU

GRN

BLK

BLK

RED

SWITCH

STOP

SW3:

BRN

BLK
/16

RED
/16

CUT-OUT

THERMAL

MG

GRILL HEATER (TOP)

ORG

/18

RED

/16

BLK

BLK

/18

BLK
/18

BLU
/18

ORG

ORG

/18

/18

BLU

/18

WHT

BLK

RED

GRY/18

F8A

F2:

FUSE

SWITCH

LATCH

SW1:
MONITORED

SW2:

F1: FUSE 15A

BLU

BRN

ORG

RED

150/130 C

125/95 C

NO INDICATION SHOWS WIRE THICKNESS AWG22

/18: WIRE THICKNESS = AWG18

/16: WIRE THICKNESS = AWG16

HV: HIGH VOLTAGE WIRE

G-Y=GREEN & YELLOW STRIPE

ORG=ORANGE      GRY=GREY

BRN=BROWN   BLU=BLUE

RED=RED      WHT=WHITE

WIRE COLOUR CODE & SYMBOL

230-240V  50Hz

2.CLOCK APPEARS ON DISPLAY

1.DOOR CLOSED

NOTE:CONDITION OF OVEN

SCHEMATIC

HV

HV

* INDICATES PARTS WITH POTENTIALS OVER 240V

*

*

*

*

*

16

891M -

BLU

BLU

BLU

BLK

WHT

BLU

BLK

BRN

WHT

BLU

ORG

BLK

RED

RED

ORG

ORG

BLK

1

GRN

2

RED

OVEN

CAPACITOR

VOLTAGE

HIGH

SHORT

PROTECTOR

RECTIFIER

HV WIRE B

HV WIRE A

POWER TRANSFORMER

MAGNETRON

STOP

TOP HEATER

MAGNETRON

THERMAL

THERMAL

CUT-OUT

CUT-OUT

TOUCH CONTROL PANEL

HIGH VOLTAGE COMPONENTS

SWITCH

MONITORED

LATCH

MONITOR SWITCH

SWITCH

MOTOR

CONVECTION

THERMISTOR

UNIT

FILTER

NOISE

MAINS SUPPLY CORD

FAN MOTOR

OVEN LAMP

TURNTABLE

MOTOR

BOTTOM HEATER

TRANSFORMER

LOW VOLTAGE

4

BLK

BLK

2

1

3

COM

NO

NO

COM

COM

NO

NO

COM

RY3

RY1

RY2

RY4

CN-A

CN-E

CN-B

CN-C

BLU

BRN

G/Y

LIVE

NEUTRAL

EARTH

WHT

WHT

BLK

BLU

GRY

BRN

WHT

GRY

RED

BLU

WHT

ORG

WHT

WHT

GRY

GRN

RED

BLU WHT

GRY GRY

WHT GRY

BLK

WHT

WHT

WHT

ORG

BLK

ORG

RED

BLU

RED

BLU

BLK

BRN

6

7

BLU

1

RED

2

3

ORG

5

4

67

12

3

5

BLK

RED

BRN

WHT

17

891M -

C O M

C O M

C O M

C   1

C   3

B   2

B   1

E   1

F 1 1

F 1 0

F   2

F   1

F 1 2

F   7

F   9

F   8

F   3

F   6

F   4

F   5

F 1 3

F 1 5

F 1 4

E   3

R 2   3 9 0   1 w

R 5   1 . 3 k

A C 2 4 0 V
5 0 H z

F A N
M O T O R

C O N V E C T I O N
M O T O R

O V E N   L A M P
T U R N T A B L E
M O T O R

L O W E R
H E A T E R

U P P E R
H E A T E R

H I G H
V O L T A G E
T R A N S F O R M E R  

N O T E

:   I F   N O T   S P E C I F I E D ,   1 / 4 w  

±

  5 %

:   I F   N O T   S P E C I F I E D ,   1 S S 2 7 0 A

O V E N
T H E R M I S T O R

D O O R
S W I T C H

R 1 0   1 . 5 k

R 8   8 2   1 / 2 w

R 9   8 2   1 / 2 w

R 7   1 1 0   1 / 2 w

C1 0.1

µ

/50v 

C4 0.1

µ

/50v 

C5 10

µ

/35v 

C2 1000

µ

/35v

C3 10

µ

/35v

C6 10

µ

/35v

R1 2.4k

R4 1.3k

D2

(J1)

D3

D4

D5

D6

D7

R6 3.3k

SP1

ZD1

HZ16-3

ZD2

HZ20-2

a

b

cd

ZD3

HZ20-1

Q 1
2 S B 1 2 3 8

V R S 1
1 0 G 4 7 1 K

R Y 5

R Y 6

R Y 1

R Y 4

R Y 3

R Y 2

Q 2
2 S B 1 2 3 8

Q 4
2 S B 1 2 3 8

Q 3
K R C 2 4 3 M

D 1
S 1 N B 1 0

T 1

E   5

E   7

A   3

A   1

A   5

A   7

N O

C O M

N O

N O

N O

+

–

+

–

+

–

+

–