Sharp R930cs Service Manual

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R-930CS
Figure O-2. Oven Schematic-Microwave Cooking Condition
SCHEMATIC
1. DOOR CLOSED.
2. COOKING TIME PROGRAMMED.
3. ÒSTARTÓ PAD TOUCHED.
Figure O-1. Oven Schematic-OFF Condition
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED.
2. CLOCK APPEARS ON DISPLAY.
SCHEMATIC DIAGRAM
IMPORTANT:
During sensor cooking operation, the fire sensing op-
eration sequence will not begin until the AH sensor hasdetected vapors and initiated a sensor cooking cycle.
This is because the operation of the convection fan...

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R-930CS
DESCRIPTION AND FUNCTION OF COMPONENTS
SCHEMATIC
1. DOOR CLOSED.
2. CONVECTION PAD TOUCHED.
3. DESIRED TEMP. TOUCHED.
4. COOKING TIME PROGRAMMED.
5. ÒSTARTÓ PAD TOUCHED.
SCHEMATIC
1. DOOR CLOSED.
2. MIX COOKING PAD TOUCHED.
3. COOKING TIME PROGRAMMED.
4. ÒSTARTÓ PAD TOUCHED.
5. RY2 AND RY3 WILL ALTERNATELY CLOSE.
DURING COOK CYCLE.
Figure O-4. Oven Schematic-Convection Cooking Condition Figure O-3. Oven Schematic-Automatic Mix Cooking Condition
CONV.
THERMAL
CUT-OUT
MONITOR SWITCH OVEN LAMP...

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R-930CS
condition develops in the magnetron due to cooling fan
failure, obstructed air guide, dirty or blocked air intake, etc.
Under normal operation, the temperature fuse remains
closed. However, when abnormally high temperatures are
reached within the magnetron, the temperature fuse will
open at 302ûF(150ûC) causing the oven to shut down.
CONV. THERMAL CUT-OUT
The thermal cut-out located on the left side of the thermal
protection plate (left) is designed to prevent damage to the
heater unit if an...

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R-930CS
air is channelled through the cavity to remove steam and
vapors given off from the heating foods. It is then exhausted
at the top of the oven cavity into a condensation compartment.
Convection Cooking:
Damper is in the closed position, so that no hot air will be
allowed to leak out the oven cavity.
Damper Operation
1. When power supply cord is plugged in:
1-1. When power supply cord is plugged in, a signal is
sensed in the control unit, and operates shut-off
relay (RY4).
1-2. Contacts of...

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R-930CS
A MAGNETRON
B POWER TRANSFORMER
C H.V. RECTIFIER ASSEMBLY
D HIGH VOLTAGE CAPACITOR
E SECONDARY INTERLOCK SWITCH
F PRIMARY INTERLOCK SYSTEM
G MONITOR SWITCH
H MONITOR FUSE
I MAGNETRON TEMPERATURE FUSE
J CONV. THERMAL CUT-OUT
K CONVECTION HEATER
L THERMISTOR
M DAMPER MOTOR
N DAMPER SWITCH
P TOUCH CONTROL PANEL
Q KEY UNIT
R RELAY RY-1
R RELAY RY-2
R RELAY RY-3
R RELAY RY-4
R RELAY RY-5
R RELAY RY-6
S COMP. DEFROST
T FOIL PATERN ON PWB.
U AH SENSOR
ReplaceOVEN LAMP OR SOCKET
ReplaceFAN MOTOR...

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R-930CS
TEST PROCEDURES
PROCEDURE
LETTERCOMPONENT TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. To test for an open filament, isolate the magnetron from the high voltage circuit. A continuity check
across the magnetron filament leads should indicate less than 1 ohm.
5. To test for a shorted magnetron, connect the ohmmeter leads between the magnetron filament leads
and chassis ground. This test should...

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R-930CS
CHIGH VOLTAGE RECTIFIER TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Isolate the rectifier from the circuit. Using the highest ohm scale of the meter, read the resistance
across the terminals and observe, reverse the leads to the rectifier terminals and observe meter
reading. If a short is indicated in both directions, or if an infinite resistance is read in both directions,
the rectifier is...

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R-930CS
TEST PROCEDURES
PROCEDURE
LETTERCOMPONENT TEST
5. Reconnect all leads removed from components during testing.
6. Reinstall the outer case (cabinet).
7. Reconnect the power supply cord after the outer case is installed.
8. Run the oven and check all functions.
NOTE: If the door sensing switch contacts fail in the open position and the door is closed, the turntable
motor and oven light will be activated by RY1.
PRIMARY INTERLOCK RELAY (RY2)
1. Disconnect the power supply cord, and then remove...

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R-930CS
TEST PROCEDURES
PROCEDURE
LETTERCOMPONENT TEST
IMAGNETRON TEMPERATURE FUSE TEST
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. A continuity check across the temperature fuse terminals should indicate a closed circuit unless the
temperature of the magnetron reaches approximately 302ûF(150ûC). An open temperature fuse
indicates overheating of the magnetron. Check for restricted air flow to the...

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R-930CS
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Disconnect the leads to the primary of the power transformer.
5. Ensure that the leads remain isolated from other components and oven chassis by using insulation tape.
6. Disconnect the wire leads from the switch terminals and connect ohmmeter leads to the common
(COM.) and normally open (N.O.) terminals of the switch.
6-1. When switch actuator is pushed...