Sharp R-872M (serv.man5) Service Manual ▷ View online
R-872M - 29
MICROWAVE MEASUREMENT
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
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.
PREPARATION
The following items are required to carry out this test:-
1. A low form of 600 ml beaker made from an electrically
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
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 standard whose accu-
racy can be traced to National Physical Laboratory
Standards.
racy can be traced to National Physical Laboratory
Standards.
Recommended instruments are:
Apollo "XI"
Celtec "A100"
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.
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.
PROCEDURE
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.
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.
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
b) across the face of the door
c) across any vents in the oven's sides, rear or top
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.
Dotted line indicates the path taken by the leakage detec-
tor.
tor.
R-872M - 30
Note:
AC CORD CONNECTION
BRN :
AC CORD CONNECTION
BRN :
BROWN
BLU :
BLUE
G-Y :
GREEN AND YELLOW STRIPE
/15 :
SECTIONAL AREA OF 1.5mm
2
MIN.
"
"
Indicates components with potential
above 250 V.
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. "ENERGY SAVED MODE" APPEARS ON DISPLAY.
1. DOOR CLOSED.
2. "ENERGY SAVED MODE" APPEARS ON DISPLAY.
Figure O-1(c) Oven Schematic-OFF Condition after the oven door is closed.
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. " . O" APPEARS ON DISPLAY.
1. DOOR CLOSED.
2. " . O" APPEARS ON DISPLAY.
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. PLUGGED IN OVEN.
3. NOTHING APPEARS ON DISPLAY.
1. DOOR CLOSED.
2. PLUGGED IN OVEN.
3. NOTHING APPEARS ON DISPLAY.
Figure O-1(a) Oven Schematic-OFF Condition right after the oven is plugged in.
Figure O-1(b) Oven Schematic-OFF Condition when the oven door is opened.
OL
CM
TTM
OVEN LAMP
CONVECTION
MOTOR
FAN MOTOR
TURNTABLE MOTOR
TOP GRILL HEATING ELEMENT
BOTTOM HEATING ELEMENT
H.V. RECTIFIER
MAGNETRON
HIGH VOLTAGE
TRANSFORMER
T/C TRANSFORMER
CAPACITOR
1.07
µ
F
AC2100V
CONTROL UNIT
A9
A7
RY7
RY5
COM.
COM.
COM.
N.O.
N.O.
COM.
N.O.
N.O.
A3
E1
E3
E5
E7
A1
B2
C3
C1
A5
B1
(SW2)STOP SWITCH
(SW1)MONITORED LATCH SWITCH
THERMISTOR
MG.
THERMAL
CUT-OUT
THERMAL
CUT-OUT
OVEN
THERMAL
CUT-OUT
THERMAL
CUT-OUT
(SW3)MONITOR
SWITCH
SWITCH
4700p/ 250V
4700p/ 250V
10M/ 0.5W
NOISE SUPPRESSION COIL
680 k/ 0.5W
0.22
µ
/250V
FUSE 15A
FUSE F8A
NOISE
FILTER
FILTER
L
N
230 - 240V ~ 50Hz
BRN/15
BLU/15
G-Y/15
EARTH
LIVE
NEUTRAL
NC.
NC.
ASYMMETRIC
RECTIFIER
RECTIFIER
RY6
RY1
RY2
RY3
RY4
FM
1
-
OL
CM
TTM
OVEN LAMP
CONVECTION
MOTOR
FAN MOTOR
TURNTABLE MOTOR
TOP GRILL HEATING ELEMENT
BOTTOM HEATING ELEMENT
H.V. RECTIFIER
MAGNETRON
HIGH VOLTAGE
TRANSFORMER
T/C TRANSFORMER
CAPACITOR
1.07
µ
F
AC2100V
CONTROL UNIT
A9
A7
RY7
RY5
COM.
COM.
COM.
N.O.
N.O.
COM.
N.O.
N.O.
A3
E1
E3
E5
E7
A1
B2
C3
C1
A5
B1
(SW2)STOP SWITCH
(SW1)MONITORED LATCH SWITCH
THERMISTOR
MG.
THERMAL
CUT-OUT
THERMAL
CUT-OUT
OVEN
THERMAL
CUT-OUT
THERMAL
CUT-OUT
(SW3)MONITOR
SWITCH
SWITCH
4700p/ 250V
4700p/ 250V
10M/ 0.5W
NOISE SUPPRESSION COIL
680 k/ 0.5W
0.22
µ
/250V
FUSE 15A
FUSE F8A
NOISE
FILTER
FILTER
L
N
230 - 240V ~ 50Hz
BRN/15
BLU/15
G-Y/15
EARTH
LIVE
NEUTRAL
NC.
NC.
ASYMMETRIC
RECTIFIER
RECTIFIER
RY6
RY1
RY2
RY3
RY4
FM
1
-
OL
CM
TTM
OVEN LAMP
CONVECTION
MOTOR
FAN MOTOR
TURNTABLE MOTOR
TOP GRILL HEATING ELEMENT
BOTTOM HEATING ELEMENT
H.V. RECTIFIER
MAGNETRON
HIGH VOLTAGE
TRANSFORMER
T/C TRANSFORMER
CAPACITOR
1.07
µ
F
AC2100V
CONTROL UNIT
A9
A7
RY7
RY5
COM.
COM.
COM.
N.O.
N.O.
COM.
N.O.
N.O.
A3
E1
E3
E5
E7
A1
B2
C3
C1
A5
B1
(SW2)STOP SWITCH
(SW1)MONITORED LATCH SWITCH
THERMISTOR
MG.
THERMAL
CUT-OUT
THERMAL
CUT-OUT
OVEN
THERMAL
CUT-OUT
THERMAL
CUT-OUT
(SW3)MONITOR
SWITCH
SWITCH
4700p/ 250V
4700p/ 250V
10M/ 0.5W
NOISE SUPPRESSION COIL
680 k/ 0.5W
0.22
µ
/250V
FUSE 15A
FUSE F8A
NOISE
FILTER
FILTER
L
N
230 - 240V ~ 50Hz
BRN/15
BLU/15
G-Y/15
EARTH
LIVE
NEUTRAL
NC.
NC.
ASYMMETRIC
RECTIFIER
RECTIFIER
RY6
RY1
RY2
RY3
RY4
FM
1
-
SCHEMATIC
R-872M - 31
Figure O-2 Oven Schematic-Microwave cooking Condition
Figure O-3(a) Oven Schematic-Grill cooking Condition (TOP GRILL mode)
SCHEMATIC
NOTE: CONDITION OF OVEN
1.
DOOR CLOSED.
2.
COOKING TIME ENTERED.
3.
START KEY TOUCHED.
SCHEMATIC
NOTE: CONDITION OF OVEN
1.
DOOR CLOSED.
2.
COOKING TIME ENTERED.
3.
TOP GRILL MODE SELECTED.
4.
START KEY TOUCHED.
OL
CM
TTM
OVEN LAMP
CONVECTION
MOTOR
MOTOR
FAN MOTOR
TURNTABLE MOTOR
TOP GRILL HEATING ELEMENT
BOTTOM HEATING ELEMENT
H.V. RECTIFIER
MAGNETRON
HIGH VOLTAGE
TRANSFORMER
TRANSFORMER
T/C TRANSFORMER
CAPACITOR
1.07
1.07
µ
F
AC2100V
CONTROL UNIT
A9
A7
RY7
RY5
COM.
COM.
COM.
N.O.
N.O.
COM.
N.O.
N.O.
A3
E1
E3
E5
E7
A1
B2
C3
C1
A5
B1
(SW2)STOP SWITCH
(SW1)MONITORED LATCH SWITCH
THERMISTOR
MG.
THERMAL
CUT-OUT
OVEN
THERMAL
CUT-OUT
(SW3)MONITOR
SWITCH
4700p/ 250V
4700p/ 250V
10M/ 0.5W
NOISE SUPPRESSION COIL
680 k/ 0.5W
0.22
µ
/250V
FUSE 15A
FUSE F8A
NOISE
FILTER
L
N
230 - 240V ~ 50Hz
BRN/15
BLU/15
G-Y/15
EARTH
LIVE
NEUTRAL
NC.
NC.
ASYMMETRIC
RECTIFIER
RY6
RY1
RY2
RY3
RY4
FM
1
-
OL
CM
TTM
OVEN LAMP
CONVECTION
MOTOR
MOTOR
FAN MOTOR
TURNTABLE MOTOR
TOP GRILL HEATING ELEMENT
BOTTOM HEATING ELEMENT
H.V. RECTIFIER
MAGNETRON
HIGH VOLTAGE
TRANSFORMER
TRANSFORMER
T/C TRANSFORMER
CAPACITOR
1.07
1.07
µ
F
AC2100V
CONTROL UNIT
A9
A7
RY7
RY5
COM.
COM.
COM.
N.O.
N.O.
COM.
N.O.
N.O.
A3
E1
E3
E5
E7
A1
B2
C3
C1
A5
B1
(SW2)STOP SWITCH
(SW1)MONITORED LATCH SWITCH
THERMISTOR
MG.
THERMAL
CUT-OUT
:
OVEN
THERMAL
CUT-OUT
(SW3)MONITOR
SWITCH
4700p/ 250V
4700p/ 250V
10M/ 0.5W
NOISE SUPPRESSION COIL
680 k/ 0.5W
0.22
µ
/250V
FUSE 15A
FUSE F8A
NOISE
FILTER
L
N
230 - 240V ~ 50Hz
BRN/15
BLU/15
G-Y/15
EARTH
LIVE
NEUTRAL
NC.
NC.
ASYMMETRIC
RECTIFIER
RY6
RY1
RY2
RY3
RY4
FM
1
-
SCHEMA
TIC
R-872M - 32
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. COOKING TIME ENTERED.
3. TOP & BOTTOM GRILL MODE SELECTED.
4. START KEY TOUCHED.
1. DOOR CLOSED.
2. COOKING TIME ENTERED.
3. TOP & BOTTOM GRILL MODE SELECTED.
4. START KEY TOUCHED.
Figure O-3(c) Oven Schematic-Grill cooking Condition (TOP AND BOTTOM GRILL mode)
Figure O-3(b) Oven Schematic-Grill cooking Condition (BOTTOM GRILL mode)
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. COOKING TIME ENTERED.
3. BOTTOM GRILL MODE SELECTED.
4. START KEY TOUCHED.
1. DOOR CLOSED.
2. COOKING TIME ENTERED.
3. BOTTOM GRILL MODE SELECTED.
4. START KEY TOUCHED.
OL
CM
TTM
OVEN LAMP
CONVECTION
MOTOR
FAN MOTOR
TURNTABLE MOTOR
TOP GRILL HEATING ELEMENT
BOTTOM HEATING ELEMENT
H.V. RECTIFIER
MAGNETRON
HIGH VOLTAGE
TRANSFORMER
T/C TRANSFORMER
CAPACITOR
1.07
µ
F
AC2100V
CONTROL UNIT
A9
A7
RY7
RY5
COM.
COM.
COM.
N.O.
N.O.
COM.
N.O.
N.O.
A3
E1
E3
E5
E7
A1
B2
C3
C1
A5
B1
(SW2)STOP SWITCH
(SW1)MONITORED LATCH SWITCH
THERMISTOR
MG.
THERMAL
CUT-OUT
THERMAL
CUT-OUT
OVEN
THERMAL
CUT-OUT
THERMAL
CUT-OUT
(SW3)MONITOR
SWITCH
SWITCH
4700p/ 250V
4700p/ 250V
10M/ 0.5W
NOISE SUPPRESSION COIL
680 k/ 0.5W
0.22
µ
/250V
FUSE 15A
FUSE F8A
NOISE
FILTER
FILTER
L
N
230 - 240V ~ 50Hz
BRN/15
BLU/15
G-Y/15
EARTH
LIVE
NEUTRAL
NC.
NC.
ASYMMETRIC
RECTIFIER
RECTIFIER
RY6
RY1
RY2
RY3
RY4
FM
1
-
OL
CM
TTM
OVEN LAMP
CONVECTION
MOTOR
FAN MOTOR
TURNTABLE MOTOR
TOP GRILL HEATING ELEMENT
BOTTOM HEATING ELEMENT
H.V. RECTIFIER
MAGNETRON
HIGH VOLTAGE
TRANSFORMER
T/C TRANSFORMER
CAPACITOR
1.07
µ
F
AC2100V
CONTROL UNIT
A9
A7
RY7
RY5
COM.
COM.
COM.
N.O.
N.O.
COM.
N.O.
N.O.
A3
E1
E3
E5
E7
A1
B2
C3
C1
A5
B1
(SW2)STOP SWITCH
(SW1)MONITORED LATCH SWITCH
THERMISTOR
MG.
THERMAL
CUT-OUT
THERMAL
CUT-OUT
OVEN
THERMAL
CUT-OUT
THERMAL
CUT-OUT
(SW3)MONITOR
SWITCH
SWITCH
4700p/ 250V
4700p/ 250V
10M/ 0.5W
NOISE SUPPRESSION COIL
680 k/ 0.5W
0.22
µ
/250V
FUSE 15A
FUSE F8A
NOISE
FILTER
FILTER
L
N
230 - 240V ~ 50Hz
BRN/15
BLU/15
G-Y/15
EARTH
LIVE
NEUTRAL
NC.
NC.
ASYMMETRIC
RECTIFIER
RECTIFIER
RY6
RY1
RY2
RY3
RY4
FM
1
-
SCHEMATIC
Click on the first or last page to see other R-872M (serv.man5) service manuals if exist.