Sharp R530es Service Manual

							PRECAUTIONS TO BE OBSERVED BEFORE AND
DURING SERVICING TO AVOID POSSIBLE EXPO-
SURE TO EXCESSIVE MICROWAVE ENERGY
CHAPTER 1. WARNING TO SERVICE PERSONNEL
CHAPTER 2. MICROWAVE MEASUREMENT PRO-
CEDURE
CHAPTER 3. FOREWORD AND WARNING
CHAPTER 4. PRODUCT DESCRIPTION
CHAPTER 5. GENERAL INFORMATION
CHAPTER 6. OPERATION
CHAPTER 7. TROUBLESHOOTING GUIDE CHAPTER 8. TEST PROCEDURES
CHAPTER 9. TOUCH CONTROL PANEL ASSEMBLY
CHAPTER 10. PRECAUTIONS FOR USING LEAD-
FREE SOLDER
CHAPTER 11. COMPONENT REPLACEMENT AND 
ADJUSTMENT PROCEDURE
CHAPTER 12. CIRCUIT DIAGRAMS
Parts List
SX705R530EPW/
MICROWAVE OVEN
R-530EK-T
R-530EW-T
R-530ES-T
SERVICE MANUAL
R530EW
MODELS
CONTENTS
This document has been published to be used for
after sales service only.
The contents are subject to change without notice. TopPage
In the interest of user-safety the oven should be restored to its original condition and only parts identical to those
specified should be used.
WARNING TO SERVICE PERSONNEL: Microwave ovens contain circuitry capable of producing very high
voltage and current, contact with following parts may result in a severe, possibly fatal, electrical shock.
(High Voltage Capacitor, High Voltage Power Transformer, Magnetron, High Voltage Rectifier Assembly,
High Voltage Harness etc..)
R-530EW-T
R-530ES-T 
						

							CONTENTS
PRECAUTIONS TO BE OBSERVED BEFORE
AND DURING SERVICING TO AVOID POSSIBLE
EXPOSURE TO EXCESSIVE MICROWAVE ENER-
GY
CHAPTER 1. WARNING TO SERVICE PERSON-
NEL
[1] Before Servicing.......................................... 1-1
[2]  When the testing is completed, ................... 1-1
[3] After repairing.............................................. 1-1
CHAPTER 2. MICROWAVE MEASUREMENT 
PROCEDURE
[1] Requirements:............................................. 2-1
[2] Preparation for testing:................................ 2-1
[3] Leakage test: .............................................. 2-1
CHAPTER 3. FOREWORD AND WARNING
[1] FOREWORD............................................... 3-1
[2] WARNING ................................................... 3-1
[3] DANGER..................................................... 3-1
CHAPTER 4. PRODUCT DESCRIPTION
[1] SPECIFICATIONS ...................................... 4-1
CHAPTER 5. GENERAL INFORMATION
[1] GROUNDING INSTRUCTIONS.................. 5-1
[2] OVEN DIAGRAM ........................................ 5-1
CHAPTER 6. OPERATION
[1]  DESCRIPTION OF OPERATING SE-
QUENCE .................................................... 6-1
[2] OVEN SCHEMATIC .................................... 6-2
[3]  DESCRIPTION AND FUNCTION OF 
COMPONENTS .......................................... 6-3
CHAPTER 7. TROUBLESHOOTING GUIDE 
CHAPTER 8. TEST PROCEDURES
[1]  A: MAGNETRON ASSEMBLY TEST .......... 8-1
[2]  B: POWER TRANSFORMER TEST ........... 8-1
[3]  C: HIGH VOLTAGE RECTIFIER TEST ....... 8-1
[4]  D: HIGH VOLTAGE CAPACITOR TEST..... 8-2
[5]  E: TEMPERATURE FUSE OR THER-
MAL CUT-OUT TEST ................................. 8-2
[6]  F: SECONDARY INTERLOCK SWITCH 
AND PRIMARY INTERLOCK SYSTEM 
TEST ........................................................... 8-2
[7]  G: MONITOR SWITCH TEST ..................... 8-3
[8]  H: BLOWN MONITOR FUSE TEST ........... 8-3
[9]  I: NOISE FILTER TEST .............................. 8-4
[10]  J: TOUCH CONTROL PANEL ASSEM-
BLY TEST ................................................... 8-4[11]  K: KEY UNIT TEST..................................... 8-5
[12]  L: RELAY TEST .......................................... 8-5
[13]  M: DEFROST CENTER TEST .................... 8-6
[14]  N: FOIL PATTERN ON THE PRINTED 
WIRING BOARD TEST............................... 8-6
[15]  O: AH SENSOR TEST ................................ 8-7
CHAPTER 9. TOUCH CONTROL PANEL ASSEM-
BLY
[1]  OUTLINE OF TOUCH CONTROL PAN-
EL ............................................................... 9-1
[2]  ABSOLUTE HUMIDITY SENSOR CIR-
CUIT............................................................ 9-2
[3]  SERVICING FOR TOUCH CONTROL 
PANEL ........................................................ 9-3
CHAPTER 10. PRECAUTIONS FOR USING LEAD-
FREE SOLDER
CHAPTER 11. COMPONENT REPLACEMENT 
AND ADJUSTMENT PROCEDURE
[1] WARNINGS ...............................................11-1
[2]  OUTER CASE REMOVAL .........................11-1
[3] POWER TRANSFORMER REMOVAL ..
....11-2
[4]  HIGH VOLTAGE RECTIFIER AND HIGH 
VOLTAGE CAPACITOR REMOVAL...........11-2
[5] MAGNETRON REMOVAL .........................11-2
[6]  OVEN LAMP REMOVAL ............................11-3
[7]  POSITIVE LOCK  CONNECTOR (NO-
CASE TYPE) REMOVAL ...........................11-3
[8]  CONTROL PANEL ASSEMBLY RE-
MOVAL .......................................................11-3
[9] TURNTABLE MOTOR REMOVAL .............11-3
[10]  COOLING FAN MOTOR REMOVAL ..........11-3
[11]  DOOR SENSING SWITCH/SECOND-
ARY INTERLOCK SWITCH AND MONI-
TOR SWITCH REMOVAL ..........................11-4
[12]  DOOR SENSING SWITCH/SECOND-
ARY INTERLOCK SWITCH AND MONI-
TOR SWITCH ADJUSTMENT ...................11-4
[13] DOOR REPLACEMENT ............................11-5
CHAPTER 12. CIRCUIT DIAGRAMS
[1] Pictorial Diagram....................................... 12-1
[2]  Power Unit Circuit..................................... 12-2
[3]  LSI Unit Circuit .......................................... 12-3
[4]  Printed Wiring Board of Power Unit .......... 12-4
Parts List 
						

							R530EWT
i
R530EWTService Manual PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO AVOID
POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY
BEFOR SERVICING
PRECAUTIONS TO BE OBSERVED BEFORE AND
DURING SERVICING TO AVOID POSSIBLE
EXPOSURE TO EXCESSIVE MICROWAVE
ENERGY
(a) Do not operate or allow the oven to be operated with the door open.
(b) Make the following safety checks on all ovens to be serviced before activating the magnetron or other
microwave source, and make repairs as necessary: (1) interlock operation, (2) proper door closing, (3)
seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or loosening of hinges and
latches, (5) evidence of dropping or abuse.
(c) Before turning on microwave power for any service test or inspection within the microwave generating
compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment,
integrity, and connections.
(d) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave
generation and transmission systems shall be repaired, replaced, or adjusted by procedures described
in this manual before the oven is released to the owner.
(e) A microwave leakage check to verify compliance with the Federal Performance Standard should be
performed on each oven prior to release to the owner.
BEFORE SERVICING
Before servicing an operative unit, perform a microwave emission check as per the Microwave
Measurement Procedure outlined in this service manual.
If microwave emissions level is in excess of the specified limit, contact SHARP ELECTRONICS
CORPORATION immediately @1-800-237-4277.
If the unit operates with the door open, service person should 1) tell the user not to operate the oven
and 2) contact SHARP ELECTRONICS CORPORATION and Food and Drug Administration's
Center for Devices and Radiological Health immediately.
Service personnel should inform SHARP ELECTRONICS CORPORATION of any certified unit found
with emissions in excess of 4mW/cm . The owner of the unit should be instructed not to use the unit
until the oven has been brought into compliance.
2 
						

							R530EWT
1 – 1
R530EWTService Manual CHAPTER 1. WARNING TO SERVICE PERSONNEL
Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may result in a severe, possibly
fatal, electrical shock.
(Example)
High Voltage Capacitor, High Voltage Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc..
Read the Service Manual carefully and follow all instructions.
[1] Before Servicing
1. Disconnect the power supply cord  , and then remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
WARNING:RISK OF ELECTRIC SHOCK. DISCHARGE THE HIGH-
VOLTAGE CAPACITOR BEFORE SERVICING.
The high-voltage capacitor remains charged about 60 seconds
after the oven has been switched off. Wait for 60 seconds and
then short-circuit the connection of the high-voltage capacitor
(that is the connecting lead of the high-voltage rectifier) against
the chassis with the use of an insulated screwdriver. 
Whenever troubleshooting is performed the power supply must be dis-
connected. It may, in some cases, be necessary to connect the power
supply after the outer case has been removed, in this event,
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) 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) After that procedure, reconnect the power supply cord.
[2] When the testing is completed,
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. Reconnect the leads to the primary of the power transformer.
5. Reinstall the outer case (cabinet).
6. Reconnect the power supply cord after the outer case is installed.
7. Run the oven and check all functions.
[3] After repairing
1. Reconnect all leads removed from components during testing.
2. Reinstall the outer case (cabinet).
3. Reconnect the power supply cord after the outer case is installed.
4. Run the oven and check all functions.
Microwave ovens should not be run empty. To test for the presence of
microwave energy within a cavity, place a cup of cold water on the
oven turntable, close the door and set the power to HIGH and set the
microwave timer for two (2) minutes. When the two minutes has
elapsed (timer at zero) carefully check that the water is now hot. If the
water remains cold carry out Before Servicing procedure and re-
examine the connections to the component being tested. 
When all service work is completed and the oven is fully assembled,
the microwave power output should be checked and microwave leak-
age test should be carried out.
Don't Touch !
Danger High Voltage 
						

							R530EWT
2 – 1
R530EWTService Manual CHAPTER 2. MICROWAVE MEASUREMENT PROCEDURE
[1] Requirements:
1. Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a microwave oven should not exceed 1mW/
cm2 at any point 5cm or more from the external surface of the oven, measured prior to acquisition by a purchaser, and thereafter (through the use-
ful life of the oven), 5 mW/cm2 at any point 5cm or more from the external surface of the oven. 
2. Safety interlock switches: 
Primary interlock relay and door sensing switch shall prevent microwave radiation emission in excess of the requirement as above mentioned.
Secondary interlock switch shall prevent microwave radiation emission in excess of 5 mW/cm
2 at any point 5cm or more from the external surface
of the oven. 
[2] Preparation for testing:
Before beginning the actual measurement of leakage, proceed as follows:
1. Make sure that the actual instrument is operating normally as specified in its instruction booklet.
Important:
Survey instruments that comply with the requirement for instrumentation as prescribed by the performance standard for microwave ovens, 21 CFR
1030.10(c)(3)(i), must be used for testing.
2. Place the oven tray in the oven cavity.
3. Place the load of 275±5 ml (9.8 oz) of tap water initially at 20±5°C (68°F) in the center of the oven cavity.
The water container shall be a low form of 600 ml (20 oz) beaker with an inside diameter of approx. 8.5 cm (3-1/2 in.) and made of an electrically
nonconductive 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. Set the cooking control on Full Power Cooking Mode 
5. Close the door and select a cook cycle of several minutes. If the water begins to boil before the survey is completed, replace it with 275 ml of cool
water.
[3] Leakage test:
Closed-door leakage test (microwave measurement)
1. Grasp the probe of the survey instrument and hold it perpendicular to the gap between the door and the body of the oven.
2. Move the probe slowly, not faster than 1 in./sec. (2.5 cm/sec.) along the gap, watching for the maximum indication on the meter.
3. Check for leakage at the door screen, sheet metal seams and other accessible positions where the continuity of the metal has been breached (eg.,
around the switches, indicator, and vents).
While testing for leakage around the door pull the door away from the front of the oven as far as is permitted by the closed latch assembly.
4. Measure carefully at the point of highest leakage and make sure that the highest leakage is no greater than 4mW/cm
2, and that the secondary
interlock switch and the primary interlock relay and door sensing switch do turn the oven OFF before any door movement.
NOTE:After servicing, record data on service invoice and microwave leakage report. 
						

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3 – 1
R530EWTService Manual CHAPTER 3. FOREWORD AND WARNING
[1] FOREWORD
This Manual has been prepared to provide Sharp Electronics Corp. Service Personnel with Operation and Service Information for the SHARP
MICROWAVE OVENS, R-530EK-T, R-530EW-T and R-530ES-T.
It is recommended that service personnel carefully study the entire text of this manual so that they will be qualified to render satisfactory customer
service.
Check the interlock switches and the door seal carefully. Special attention should be given to avoid electrical shock and microwave radiation hazard.
[2] WARNING
Never operate the oven until the following points are ensured.
(A) The door is tightly closed.
(B) The door brackets and hinges are not defective.
(C) The door packing is not damaged.
(D) The door is not deformed or warped.
(E) There is no other visible damage with the oven.
Servicing and repair work must be carried out only by trained service personnel.
[3] DANGER
Certain initial parts are intentionally not grounded and present a risk of electrical shock only during servicing. Service personnel - Do not contact the
following parts while the appliance is energized; 
High Voltage Capacitor, Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness; 
If provided, Vent Hood, Fan assembly, Cooling Fan Motor.
All the parts marked “ “ on parts list are used at voltages more than 250V.
Removal of the outer wrap gives access to voltage above 250V.
All the parts marked “*“on parts list may cause undue microwave exposure, by themselves, or when they are damaged, loosened or removed. 
						

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4 – 1
R530EWTService Manual CHAPTER 4. PRODUCT DESCRIPTION
[1] SPECIFICATIONS
ITEM DESCRIPTION
Power Requirements120 Volts 
60 Hertz
Single phase, 3 wire grounded
Power Consumption 1700W / Approx. 14.3 Amperes
Power Output1200 W nominal of RF microwave energy (IEC Test procedure)
Operating frequency 2450 MHz 
Outside DimensionsWidth  24 
Height 13-3/8 
Depth  19-1/8
Cooking Cavity Dimensions
(2.0 Cubic feet)Width  17-3/8             NOTE: Internal capacity is calculated by measuring 
Height   10-1/2                      maximum width, depth and height.
Depth  18-5/8                       Actual capacity for holding food is less.
Control ComplementTouch Control System
Clock (1:00 - 12:59)
Timer (0 - 99 minutes 99 seconds)
Microwave Power for Variable Cooking
Repetition Rate;
      100 PERCENT ............................. Full power throughout the cooking time
       90 PERCENT ............................................... approx. 90% of Full Power
       80 PERCENT ............................................... approx. 80% of Full Power
       70 PERCENT ............................................... approx. 70% of Full Power
       60 PERCENT ............................................... approx. 60% of Full Power
       50 PERCENT ............................................... approx. 50% of Full Power
       40 PERCENT ............................................... approx. 40% of Full Power
       30 PERCENT .............................................. approx. 30% of Full Power
       20 PERCENT ............................................... approx. 20% of Full Power
       10 PERCENT ............................................... approx. 10% of Full Power
       0 PERCENT .............................. No power throughout the cooking time
Sensor Cooking pads
Breakfast pad
Lunch pad
15 Minute Recipes pad
Defrost Center pad
From the Pantry pad
Beverage Center pad
Number selection pads
Timer/Clock pad
Keep Warm Plus pad
Minute Plus pad
Power Level pad
Stop/Clear pad
Start/Touch On pad
Oven Cavity Light Yes
Safety StandardUL listed   FCC Authorized
DHHS Rules, CFR, Title 21, Chapter 1, Subchapter J 
						

							R530EWT
5 – 1
R530EWTService Manual CHAPTER 5. GENERAL INFORMATION
[1] GROUNDING INSTRUCTIONS
This oven is equipped with a three prong grounding plug. It must be plugged into a wall receptacle that is properly installed and grounded in accor-
dance with the National Electrical Code and local codes and ordinances.
In the event of an electrical short circuit, grounding reduces the risk of electric shock by providing an escape wire for the electric current.
WARNING:
Improper use of the grounding plug can result in a risk of electric shock.
Electrical Requirements
The electrical requirements are a 120 volt 60 Hz, AC only, 15 or 20 amp. fused electrical supply. It
is recommended that a separate circuit serving only this appliance be provided. When installing
this appliance, observe all applicable codes and ordinances. A short power-supply cord is provided
to reduce risks of becoming entangled in or tripping over a longer cord. Where a two-pronged wall-
receptacle is encountered, it is the personal responsibility and obligation of the customer to contact
a qualified electrician and have it replaced with a properly grounded three-pronged wall receptacle
or have a grounding adapter properly grounded and polarized. If the extension cord must be used,
it should be a 3-wire, 15 amp. or higher rated cord. Do not drape over a countertop or table where
it can be pulled on by children or tripped over accidentally.
CAUTION: DO NOT UNDER ANY CIRCUMSTANCES CUT OR REMOVE THE ROUND
GROUNDING PRONG FROM THIS PLUG. 
[2] OVEN DIAGRAM
1. OVEN
1. One touch door open button.
Push to open door.
2. Door latches.
The oven will not operate unless the door is securely closed.
3. Removable turntable support
4. Removable turntable.
The turntable will rotate clockwise or counterclockwise.
5. Oven lamp.
It will light when oven is operating or door is opened.
6. Oven door with see-through window
7. Ventilation openings. (Rear)
8. Auto-Touch control panel.
9. Time display: Digital display, 99 minutes, 99 seconds.10.Waveguide cover: 
11. Power supply cord.
2. TOUCH CONTROL PANEL
NOTE:Some one-touch cooking features such as “MINUTE
PLUS” are disabled after three minutes when the oven is
not in use. These features are automatically enabled when
the door is opened and closed or the STOP/ CLEAR pad is
pressed.
3-Pronged
PlugGrounded
Receptacle Box
Grounding Pin
3-Pronged Receptacle
1
65
2
10
119
78
3
4SENSOR COOKING
LET'S COOK FROZEN FOODS
Popcorn
Fresh
vegetables
Ground
meatSensor
reheatCUSTOM
HELP
Rice
PoultryBaked
potatoes
Fish
Seafood
Snacks Vegetables Entrees
Defrost
CenterFrom the
PantryBeverage
Center Breakfast Lunch15 Minute
Recipes
Power
Level
Minute
Plus
StartTouch On
Keep WarmPlus
3 2 145
8 7 690
R-530EW-T/K-T
R-530ES-T 
						

							R530EWT
6 – 1
R530EWTService Manual CHAPTER 6. OPERATION
[1] DESCRIPTION OF OPERATING SEQUENCE 
The following is a description of component functions during oven operation.
1. OFF CONDITION
Closing the door activates the door sensing switch and secondary
interlock switch. (In this condition, the monitor switch contacts are
opened.)
When oven is plugged in, 120 volts A.C. is supplied to the control unit.
(Figure O-1).
1) The display will show “SHARP SIMPLY THE BEST PRESS CLEAR
AND PRESS CLOCK”.
To set any program or set the clock, you must first touch the STOP/
CLEAR pad. The display will clear, and   :   will appear.
2. COOKING CONDITION
Program desired cooking time by touching the NUMBER pads. Pro-
gram the power level (100%) by touching the POWER LEVEL pad
once. When the START pad is touched, the following operations occur:
1) The contacts of relays are closed and components connected to
the relays are turned on as follows.
(For details, refer to Figure O-2)
2) 120 volts A.C. is supplied to the primary winding of the power trans-
former and is converted to about 3.64 volts A.C. output on the fila-
ment winding, and approximately 2400 volts A.C. on the high
voltage winding.
3) The filament winding voltage heats the magnetron filament and the
H.V. winding voltage is sent to a voltage doubler circuit.
4) The microwave energy produced by the magnetron is channelled
through the waveguide into the cavity feed-box, and then into the
cavity where the food is placed to be cooked.
5) Upon completion of the cooking time, the power transformer, oven
lamp, etc. are turned off, and the generation of microwave energy
is stopped. The oven will revert to the OFF condition.
6) When the door is opened during a cook cycle, the monitor witch,
door sensing switch, secondary interlock switch, relay (RY1) and
primary interlock relay are activated with the following results. The
circuits to the turntable motor, the cooling fan motor, and the high
voltage components are de-energized, the oven lamp remains on,
and the digital read-out displays the time still remaining in the cook
cycle when the door was opened.
7) The monitor switch electrically monitors the operation of the sec-
ondary interlock switch and primary interlock relay and is mechani-
cally associated with the door so that it will function in the following
sequence.
a) When the door opens from the closed position, the primary
interlock relay (RY2) and secondary interlock switch open their
contacts. And contacts of the relay (RY1) remains closed. Then
the monitor switch contacts close. 
b) When the door is closed from the open position, the monitor
switch contacts open first. Then the contacts of the secondary
interlock switch and door sensing switch close. And contacts of
the relay (RY1) open.
If the secondary interlock switch and primary interlock relay (RY2) fail
with the contacts closed when the door is opened, the closing of the
monitor switch contacts will form a short circuit through the monitor
fuse, secondary interlock switch, relay (RY1) and primary interlock
relay (RY2), causing the monitor fuse to blow.
3. POWER LEVEL P-0 TO P-90 COOKING
When Variable Cooking Power is programmed, the 120 volts A.C. is
supplied to the power transformer intermittently through the contacts of
relay (RY-2) which is operated by the control unit within a 32 second
time base. Microwave power operation is as follows:
NOTE:The ON/OFF time ratio does not correspond with the per-
centage of microwave power, because approx. 3 seconds
are needed for heating of the magnetron filament.
4. SENSOR COOKING CONDITION
Using the SENSOR function, the food is cooked without figuring time,
power level or quantity. When the oven senses enough steam from the
food, it relays the information to its microprocessor which will calculate
the remaining cooking time and power level needed for best results.
When the food is cooked, water vapor is developed. The sensor
“senses” the vapor and its resistance increases gradually. When the
resistance reaches the value set according to the menu, supplemen-
tary cooking is started. The time of supplementary cooking is deter-
mined by experiment with each food category and inputted into the
LSI.
An example of how sensor works: (POTATOES)
1. Potatoes at room temperature. Vapor is emitted very slowly.
2. Heat potatoes. Moisture and humidity is emitted rapidly. You can
smell the aroma as it cooks.; RELAY CONNECTED COMPONENTS
RY-1  oven lamp/turntable motor/fan motor
RY-2 power transformer
VARI-MODE ON TIME OFF TIME
100 PERCENT (100% power)  32 sec. 0 sec.
90 PERCENT (approx. 90% power)       30  sec. 2  sec.
80 PERCENT (approx. 80% power)       26  sec. 6  sec.
70 PERCENT (approx. 70% power)       24  sec. 8  sec.
60 PERCENT (approx. 60% power)       22  sec. 10  sec.
50 PERCENT (approx. 50% power)       18  sec. 14  sec.
40 PERCENT (approx. 40% power)       16  sec. 16  sec.
30 PERCENT (approx. 30% power)       12  sec. 20  sec.
20 PERCENT (approx. 20% power)         8  sec. 24  sec.
10 PERCENT (approx. 10% power)         6  sec. 26  sec.
0 PERCENT (0% power)        0 sec. 32 sec.
MICROWAVE 
						

							R530EWT
6 – 2
3. Sensor detects moisture and humidity and calculates cooking time
and variable power.
4.1. Cooking Sequence.
1. Operate the oven in sensor cooking mode by referring to the opera-
tion manual.
NOTE: The oven should not be operated on SENSOR immediately
after plugging in the unit. Wait two minutes before cooking on
SENSOR.2. The coil of shut-off relay (RY-1) is energized, the turntable motor,
oven lamp and cooling fan motor are turned on, but the power
transformer is not turned on.
3. After about 16 seconds, the cook relay (RY-2) is energized. The
power transformer is turned on, microwave energy is produced and
first stage is started. The 16 seconds is the cooling time required to
remove any vapor from the oven cavity and sensor.
NOTE: During this first stage, do not open the door or touch STOP/
CLEAR pad.
4. When the sensor detects the vapor emitted from the food, the dis-
play switches over to the remaining cooking time and the timer
counts down to zero. At this time, the door may be opened to stir,
turn, or season food.
5. When the timer reaches zero, an audible signal sounds. The shut-
off relay and cook relay are de-energized and the power trans-
former, oven lamp, etc. are turned off.
6. Opening the door or touching the STOP/CLEAR pad, the time of
day will reappear on the display and the oven will revert to an OFF
condition.
[2] OVEN SCHEMATIC
1. Off Condition
                                                                              Figure O-1. Oven Schematic-Off Condition
MICROWAVEAH SENSOR
SCHEMATIC
NOTE: CONDITION OF OVEN
1. DOOR CLOSED
2. CLOCK APPEARS ON DISPLAY
NOTE: " " indicates components with potentials above 250V
C3 C2
C1
NOISE
FILTER
MONITOR
FUSE (20A) R2
120V
AC60 Hz
FAN
MOTORMONITOR
SWITCH
H.V. RECTIFIER
MAGNETRON
TTM
OL FMCAVITY
TEMP.
FUSE
MAGNETRON
TEMP. FUSE
A1 A2
COM. COM. N.O.
N.C.
DOOR
SENSING
SWITCH (RY-1)(RY-2)
PRIMARY
INTERLOCK
RELAY
CONTROL UNIT
B1 B2 GRN
POWER
TRANSFORMERCAPACITOR
1.0mF AC 2300V
F3
F1F2
AH SENSOR
SECONDARY
INTERLOCKS
WITCH OVEN
LAMPTURN-
TABLE
MOTOR