DOWNLOAD Sharp R-22FBSTM Service Manual ↓ Size: 876.36 KB | Pages: 35 in PDF or view online for FREE

R-21FBSTM/R-22FBSTM - 25

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 require-
ments of the performance standard for microwave oven.

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.

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 center 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.

R-21FBSTM/R-22FBSTM - 26

Parts

Symbol

Value / Data

Thermal cut-out (OVEN)

TC01

125

°

C

Oven lamp

OL

240-250V 25W

High voltage capacitor

C

0.91

µ

 AC 2100V

Magnetron

MG

Filament < 1

Ω

Filament – chassis 

∞

 ohm.

Power transformer

T

Filament winding < 1

Ω

Secondary winding Approx. 160

Ω

Primary winding Approx. 2.

Ω

Fuse

F1

F8A 250V

Thermal cut-out(Magnetron)

TC02

125

°

C

WARNING: WIRING / RE-WIRING.
Before carrying out any work; carry out 3D checks.
1. Disconnect the supply
2. Door opened.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, any motor, switch).

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.

R-21FBSTM/R-22FBSTM - 27

*INDICATES COMPONENTS WITH
  POTENTIAL ABOVE 250V

T: HIGH VOLTAGE
  TRANSFORMER
 

MG: MAGNETRON

 H.V. RECTIFIER

C:

H.V. CAPACITOR

0.91

µ

F/ AC2100V

TURNTABLE

 MOTOR

FAN MOTOR

OVEN LAMP

TC: OVEN THERMAL 
 

CUT-OUT 125˚C 

SW1: 
MONITORED 
LATCH SWITCH 

SW2: 
MONITOR
SWITCH 

A1

OL

FM

TTM

N.C.

COM.

EARTH

BLU

BRN

LIVE

NEUTRAL

G-Y

F1: FUSE 
   ( F8A)

N

L

0.22

µ

/AC250V 

680K/ 0.5W 

10M/ 0.5W 

NOISE SUPPRESSION COIL 

0.0033

µ

/ 250V

0.0033

µ

/ 250V

NOISE FILTER

230-240V 

˜

 

50Hz (R-21/22FBSTM)

 TRANSFORMATEUR T/C

COM.

COM.

N.O.

N.O.

A3

B2

A5

B1 

RY1

RY4

RY3

COM.

N.O.

N.O.

SW3: STOP SWITCH 

TC02: MAGNETRON THERMAL 
 

    CUT-OUT 125˚C 

T: HIGH VOLTAGE
  TRANSFORMER

MG: MAGNETRON

 H.V. RECTIFIER

C:

H.V. CAPACITOR

0.91

µ

F/ AC2100V

TURNTABLE

 MOTOR

FAN MOTOR

OVEN LAMP

TC: OVEN THERMAL 
 

CUT-OUT 125˚C 

SW1: 
MONITORED 
LATCH SWITCH 

SW2: 
MONITOR
SWITCH 

A1

OL

FM

TTM

N.C.

COM.

EARTH

BLU

BRN

LIVE

NEUTRAL

G-Y

F1: FUSE 
   ( F8A)

N

L

0.22

µ

/AC250V 

680K/ 0.5W 

10M/ 0.5W 

NOISE SUPPRESSION COIL 

0.0033

µ

/ 250V

0.0033

µ

/ 250V

NOISE FILTER

230-240V 

˜

 

50Hz (R-21/22FBSTM)

 TRANSFORMATEUR T/C

COM.

COM.

N.O.

N.O.

A3

B2

A5

B1 

RY1

RY4

RY3

COM.

N.O.

N.O.

SW3: STOP SWITCH 

TC02: MAGNETRON THERMAL 
 

    CUT-OUT 125˚C 

R-21FBSTM/R-22FBSTM - 28

BLUE

BROWN

GRN/YL

MAINS SUPPLY CORD

NOISE FILTER UNIT

FAN MOTOR

OVEN 

THERMAL 

CUTOUT

OVEN LAMP

TURNTABLE  MOTOR

STOP SWITCH

        MONITORED LATCH  SWITC

H

MONITOR SWITCH

RED

GRN

BLU

BRN

RED

WHT

WHT

O

R

G

BLK

BLK

RED

ORG

WHT

WHT

GRY

WHT

WHT

WHT

WHT

RED

RED

BRN

WHT

W

H

T

WHT

B

R

N

B

R

N

MAG. 

THERMAL 

CUTOUT

 CN-B

 CN-C

RED

GRN

1

2

 CN-E

CN-A

ORG

WHT

3

BLK

5

BLK

BRN

RED

BLK

ORG

BLK

1

RED

 CN-F

  CONTROL UNIT

 WH-F

 WH-C

HIGH VOL

TA

G

E 

C

OMPONENET

S

             

MA

GNETRON

SHORT

PRO

TECT

OR

HV RECTIFIER

HV CAP

A

CIT

O

R

POWER TRANSFORMER

   

   

   

       

  S

W

ITC

H

 U

N

IT 

  

 LE

D B

O

A

R

D

R

-21/22

/FB

ST

M