Sharp R-362M (serv.man2) Service Manual ▷ View online
R362M - 3
WARNING
Servicing and repair work must be carried out only by
trained service engineers.
trained service engineers.
The parts marked '*' on the parts list and schematic
diagram have voltages in excess of 250V.
diagram have voltages in excess of 250V.
Removal of the outer wrap gives access to potential
above 250V.
above 250V.
All the parts marked "
∆
" on the parts list may cause undue
microwave exposure, by themselves, or when they are
damaged, loosened or removed.
damaged, loosened or removed.
CAUTION
MICROWAVE RADIATION
Do not become exposed to radiation from the
magnetron or other parts conducting microwave
energy. All input and output microwave
connections, waveguides, flanges and gaskets must
be secured. Never operate the device without a
microwave energy absorbing load attached. Never
look into an open waveguide or antenna while the
device is energized.
magnetron or other parts conducting microwave
energy. All input and output microwave
connections, waveguides, flanges and gaskets must
be secured. Never operate the device without a
microwave energy absorbing load attached. Never
look into an open waveguide or antenna while the
device is energized.
WARNING
THIS APPLIANCE MUST BE EARTHED
.
THE WIRES IN THIS MAINS LEAD ARE COLOURED IN
ACCORDANCE WITH THE FOLLOWING CODE:
GREEN-AND-YELLOW : EARTH BLUE : NEUTRAL BROWN : LIVE
GREEN-AND-YELLOW : EARTH BLUE : NEUTRAL BROWN : LIVE
If the mains lead is replaced, only part number QACCBA032WRE2 should be used
SPECIFICATION
Power Requirements
230 -240 Volts 50 Hertz Single phase, 3 wire earthed
Power Consumption
1.45 kW
Power Output
900 watts nominal of RF microwave energy
(measured by way of IEC 705)
Operating frequency of 2450 MHz
(measured by way of IEC 705)
Operating frequency of 2450 MHz
Case Dimensions
Width 520 mm Height 305 mm including foot Depth 413 mm
Cooking Cavity Dimensions
Width 342 mm Height 207 mm Depth 368 mm
Turntable diameter
325 mm
Control Complement
Touch Control System
Clock (1.00 - 12.59 or 0.00 - 23.59)
Microwave Power for Variable Cooking
Repetition Rate:
Clock (1.00 - 12.59 or 0.00 - 23.59)
Microwave Power for Variable Cooking
Repetition Rate:
HIGH
Full power throughout the cooking time
MEDIUM HIGH
approx. 70% of FULL Power
MEDIUM
approx. 50% of FULL Power
MEDIUM LOW
approx. 30% of FULL Power
LOW
approx. 10% of FULL Power
START/AUTO MINUTE pad
AUTO COOK pad
POWER LEVEL pad
AUTO DEFROST pad
STOP/CLEAR pad
MORE/LESS pads
Time pads
Weight pads
Timer pad
SensNcook pads
Info pad
More
Less
pads
PRODUCT DESCRIPTION
CAUTION / WARNING
Set Weight
Approx. 17 kg
R362M - 4
OPERATION DATA
CONNECTED COMPONENTS
RELAY
Oven lamp, Fan motor, Turntable motor
RY5
Power transformer
RY2
Approx. 10% = 90 Watts
32 sec. ON
6 sec. ON
12 sec. ON
18 sec. ON
24 sec. ON
30 sec. OFF
20 sec. OFF
14 sec. OFF
8 sec. OFF
LOW
MEDIUM HIGH
MEDIUM
MEDIUM LOW
HIGH
Approx. 70% = 630 Watts
Approx. 50% = 450 Watts
Approx. 30% = 270 Watts
OFF CONDITION
Closing the door activates all door interlock switches (latch
switch, monitored latch switch and stop switch).
switch, monitored latch switch and stop switch).
IMPORTANT
When the oven door is closed, the monitor switch contacts
COM - NC must be open.
When the microwave oven is pluged in a wall outlet (240V
50Hz), the line voltage is supplied to the point A3+A1 in the
control unit.
When the oven door is closed, the monitor switch contacts
COM - NC must be open.
When the microwave oven is pluged in a wall outlet (240V
50Hz), the line voltage is supplied to the point A3+A1 in the
control unit.
1. The display flashes ”88:88”.
2. To set any programmes or set the clock, you must first
2. To set any programmes or set the clock, you must first
touch the STOP pad.
3. “ : ” appears in the display.
NOTE: When the oven door is opened, the oven lamp
comes on at this time.
MICROWAVE COOKING CONDITION
HIGH COOKING
Enter a desired cooking time by touching the Time pads and
start the oven by touching the START pad.
start the oven by touching the START pad.
1. The line voltage is supplied to the primary winding of the
power transformer. The voltage is converted to about
3.3 volts A.C. output on the filament winding and high
voltage of approximately 2000 volts A.C. on the
secondary winding.
3.3 volts A.C. output on the filament winding and high
voltage of approximately 2000 volts A.C. on the
secondary winding.
2. The filament winding voltage (3.3 volts) heats the
magnetron filament and the high voltage (2000 volts) is
sent to the voltagedoubling circuit, where it is doubled to
negative voltage of approximately 4000 volts D.C..
sent to the voltagedoubling circuit, where it is doubled to
negative voltage of approximately 4000 volts D.C..
3. The 2450 MHz microwave energy produced in the
magnetron generates a wave length of 12.24 cm. This
energy is channeled through the waveguide (transport
channel) into the oven cavity, where the food is placed
to be cooked.
energy is channeled through the waveguide (transport
channel) into the oven cavity, where the food is placed
to be cooked.
4. When the cooking time is up, a single tone is heard and
the relays RY5 + RY2 go back to their home position.
The circuits to the oven lamp, power transformer, fan
motor and turntable motor are cut off.
The circuits to the oven lamp, power transformer, fan
motor and turntable motor are cut off.
5. When the door is opened during a cook cycle, the
switches come to the following condition.
The circuits to the power transformer, fan motor and
turntable motor are cut off when the monitored latch
switch and stop switch are made open. The oven lamp
remains on even if the oven door is opened after the
cooking cycle has been interrupted, because the relay
RY5 stays closed. Shown in the display is the remaining
time.
turntable motor are cut off when the monitored latch
switch and stop switch are made open. The oven lamp
remains on even if the oven door is opened after the
cooking cycle has been interrupted, because the relay
RY5 stays closed. Shown in the display is the remaining
time.
6. MONITOR SWITCH CIRCUIT
The monitor switch (SW2) is mechanically controlled by
oven door, and monitors the operation of the monitored
latch switch (SW1)
oven door, and monitors the operation of the monitored
latch switch (SW1)
6-1
When the oven door is opened during or after the
cycle of cooking program, the monitored latch switch
(SW1), and stop switch (SW3) must open their contacts
first. After that the contacts (COM - NC) of the monitor
switch (SW2) can be closed.
cycle of cooking program, the monitored latch switch
(SW1), and stop switch (SW3) must open their contacts
first. After that the contacts (COM - NC) of the monitor
switch (SW2) can be closed.
6-2
When the oven door is closed, the contacts
(COM - NC) of the monitor switch (SW2) must be
opened first. After that the contacts of the monitored
latch switch (SW1) and stop switch (SW3) are closed.
(COM - NC) of the monitor switch (SW2) must be
opened first. After that the contacts of the monitored
latch switch (SW1) and stop switch (SW3) are closed.
6-3
When the oven door is opened and the contacts of the
monitored latch switch (SW1) remain closed, the fuse
(F1) F8A will blow, because the monitor switch is
closed and a short circuit is caused.
monitored latch switch (SW1) remain closed, the fuse
(F1) F8A will blow, because the monitor switch is
closed and a short circuit is caused.
MEDIUM HIGH, MEDIUM, MEDIUM LOW, LOW
COOKING
COOKING
When the microwave oven is preset for variable cooking
power, the line voltage is supplied to the power transformer
intermittently within a 32-second time base through the
relay contact which is coupled with the current-limiting relay
(RY2). The following levels of microwave power are given.
SETTING
power, the line voltage is supplied to the power transformer
intermittently within a 32-second time base through the
relay contact which is coupled with the current-limiting relay
(RY2). The following levels of microwave power are given.
SETTING
CONDITION
DURING
DOOR OPEN
SWITCH
CONTACT
COOKING
(NO COOKING)
Monitored latch switch
COM-NO
Closed
Open
Monitor switch
COM-NC
Open
Closed
Stop switch
COM-NO
Closed
Open
Monitor switch
COM-NO
Closed
Open
NOTE: The ON/OFF time ratio does not exactly correspond
to the percentage of microwave power, because
approx. 3 seconds are needed for heating up the
magnetron filament.
approx. 3 seconds are needed for heating up the
magnetron filament.
100% = 900 Watts
R362M - 5
MICROWAVE OUTPUT POWER (IEC-705)
The power output of this oven is rated using the method specified by IEC-705. Full details of how to carry out this
procedure can be found in the Sharp Technical Training notes which is available from Sharp Parts Centre
(part number SERV-LITMW01).
procedure can be found in the Sharp Technical Training notes which is available from Sharp Parts Centre
(part number SERV-LITMW01).
Using this procedure, the heating time to raise 1000g of water by 10
°
C is approximately 50 seconds.
The IEC-705 procedure must be carried out using laboratory-type procedures and equipment. These requirements
make the procedure unsuitable for routing performance checks. An indication of the power being produced by the oven
can however be obtained using the procedure given below.
make the procedure unsuitable for routing performance checks. An indication of the power being produced by the oven
can however be obtained using the procedure given below.
Alternative simplified method:
1. Place 2 litres of cold water (between 12
1. Place 2 litres of cold water (between 12
°
C and 20
°
C) in a suitable container.
2. Stir the water and measure the temperature in
°
C. Note temperature as T1.
3. Place the container in the microwave and heat the water for 2 minutes on full power.
4. When the 2 minutes is completed, remove the container and stir the water. Note the water temperature as T2.
5. Calculate the output power using the following formula:
4. When the 2 minutes is completed, remove the container and stir the water. Note the water temperature as T2.
5. Calculate the output power using the following formula:
R.F. Power Output = (T2 - T1) x 80.
Note: The result from this test should be within 10% of the power rating stated on the rating label.
MICROWAVE LEAKAGE TEST
This oven should be tested for microwave leakage on completion of any repair or adjustment, following the procedure
described in the Sharp Technical Training notes (part number SERV-LITMW01). The maximum leakage permitted in
BS EN 60335-2-25 is 50W/m
described in the Sharp Technical Training notes (part number SERV-LITMW01). The maximum leakage permitted in
BS EN 60335-2-25 is 50W/m
2
(equivalent to 5mW/cm
2
), however it is not normal to detect any significant leakage,
therefore, any leakage which is detected should be investigated.
It is essential that only leakage detectors with current calibration traceable to the National Physical Laboratories are used.
Suitable leakage detectors :
CELTEC A100
APOLLO X1
APOLLO X1
OUTPUT POWER TEST PROCEDURE
R362M - 6
TEST PROCEDURE
PROCEDURE
LETTER
A
TOUCH CONTROL PANEL ASSEMBLY TEST
COMPONENT TEST
B
KEY UNIT TEST
If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon
cable is marking good contact, verify that the door sensing switch (stop switch) operates
properly; that is the contacts are closed when the door is closed and open when the door is
open. If the door sensing switch (stop switch) is good, disconnect the flat ribbon cable that
connects the key unit to the control unit and make sure the door sensing switch is closed
(either close the door or short the door sensing switch connecter). Use the Key unit matrix
indicated on the control panel schematic and place a jumper wire between the pins that
correspond to the STOP/CLEAR pad marking momentary contact. If the control unit responds
by clearing with a beep the key unit is faulty and must be replaced. If the control unit does not
respond, it is faulty and must be replaced. If a specific pad does not respond, the above
method may be used (after clearing the control unit) to determine if the control unit or key pad
is at fault.
cable is marking good contact, verify that the door sensing switch (stop switch) operates
properly; that is the contacts are closed when the door is closed and open when the door is
open. If the door sensing switch (stop switch) is good, disconnect the flat ribbon cable that
connects the key unit to the control unit and make sure the door sensing switch is closed
(either close the door or short the door sensing switch connecter). Use the Key unit matrix
indicated on the control panel schematic and place a jumper wire between the pins that
correspond to the STOP/CLEAR pad marking momentary contact. If the control unit responds
by clearing with a beep the key unit is faulty and must be replaced. If the control unit does not
respond, it is faulty and must be replaced. If a specific pad does not respond, the above
method may be used (after clearing the control unit) to determine if the control unit or key pad
is at fault.
CARRY OUT 4R CHECKS.
The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore,
unlike conventional microwave ovens, proper maintenance can not be performed with only a voltmeter
and ohmmeter.
In this service manual, the touch control panel assembly is divided into two units, Control Unit and Key
Unit, and also the Control unit is divided into two units, CPU unit and Power unit, and troubleshooting
by replacement is described according to the symptoms indicated.
1. Key Unit Note : Check key unit ribbon connection before replacement.
unlike conventional microwave ovens, proper maintenance can not be performed with only a voltmeter
and ohmmeter.
In this service manual, the touch control panel assembly is divided into two units, Control Unit and Key
Unit, and also the Control unit is divided into two units, CPU unit and Power unit, and troubleshooting
by replacement is described according to the symptoms indicated.
1. Key Unit Note : Check key unit ribbon connection before replacement.
The following symptoms indicate a defective key unit. Replace the key unit.
a) When touching the pads, a certain pad produces no signal at all.
b) When touching a number pad, two figures or more are displayed.
c) When touching the pads, sometimes a pad produces no signal.
b) When touching a number pad, two figures or more are displayed.
c) When touching the pads, sometimes a pad produces no signal.
2. Control Panel
The following symptoms indicate a defective control unit. Before replacing the control unit.
perform the key unit test (Procedure K) to determine if control unit is faulty.
perform the key unit test (Procedure K) to determine if control unit is faulty.
2-1 In connection with pads
a) When touching the pads, a certain group of pads do not produce a signal.
b) When touching the pads, no pads produce a signal.
b) When touching the pads, no pads produce a signal.
2-2 In connection with indicators
a) At a certain digit, all or some segments do not light up.
b) At a certain digit, brightness is low.
c) Only one indicator does not light up.
d) The corresponding segments of all digits do not light up; or they continue to light up.
e) Wrong figure appears.
f) A certain group of indicators do not light up.
g) The figure of all digits flicker.
b) At a certain digit, brightness is low.
c) Only one indicator does not light up.
d) The corresponding segments of all digits do not light up; or they continue to light up.
e) Wrong figure appears.
f) A certain group of indicators do not light up.
g) The figure of all digits flicker.
2-3 Other possible troubles caused by defective control unit.
a) Buzzer does not sound or continues to sound.
b) Clock does not operate properly.
c) Cooking is not possible.
d) Proper temperature measurement is not obtained.
b) Clock does not operate properly.
c) Cooking is not possible.
d) Proper temperature measurement is not obtained.
G 8
G 7
G 6
G 5
G 4
G 3
G 2
G 1
G12
G11
G10
G 9
MORE
START
CLOCK
AUTO
MINUTE
AUTO
START
AUTO
DEFROST
AUTO
COOK
STOP/
CLEAR
POWER
LEVEL
Kg / L b
g • oz
Kg • Lb
10 sec.
1 min.
10 min.
info
TIMER
LESS
CHILLED MEALS
FRESH FISH
RICE/PASTA
SPONGE PUDDING
PORRIDGE
FROZEN MEALS JACKET POTATOES
FRESH VEG.
CANNED FOOD
