TABLE OF CONTENTS
SHARP CORPORATION
COMMERCIAL MICROWAVE OVEN
MODELS R-22AT
WARNING TO SERVICE PERSONNEL
SERVICING
REMEMBER TO CHECK 3D
WARNING AGAINST THE CHARGE OF THE TWO HIGH-VOLTAGE CAPACITORS
SHARP CORPORATION OSAKA, JAPAN
COMMERCIAL MICROWAVE OVEN R-22AT/ R-24AT
GENERAL IMPORTANT INFORMATION
MICROWAVE RADIATION
SPECIFICATION
DESCRIPTION
THIS APPLIANCE MUST BE EARTHED
PRODUCT DESCRIPTION
INSTALLATION INFORMATION
DISPLAY AND INDICATORS
APPEARANCE VIEW
AUTO TOUCH CONTROL PANEL
OPERATION SEQUENCE
IDLE CONDITION
MICROWAVE COOKING CONDITION
MICROWAVE VARIABLE COOKING
Figure B-2. Operation of Magnetron
TWO MAGNETRON OPERATION SYSTEM
Figure B-1. High Voltage Circuit
INTERLOCK SWITCHES SW1, SW2 AND STOP SWITCH SW5
MONITOR SWITCHES SW3, SW4
MAGNETRON TEMPERATURE FUSES TF1, TF2
EXHAUST TEMPERATURE FUSE TF3
TROUBLESHOOTING GUIDE
EXHAUST OVEN THERMISTOR TH3
MAGNETRON THERMISTORS TH1, TH2
BLOWER MOTOR BM
TESTPROCEDURE
POSSIBLE CAUSE AND DEFECTIVE PARTS
TEST PROCEDURES
PROCEDURE
MICROWAVE OUTPUT POWER 1 litre water load
LETTER
power
MICROWAVE OUTPUT POWER 2000 cc alternative method
TEST PROCEDURES
PROCEDURE
C HIGH VOLTAGE RECTIFIER ASSEMBLY TEST CARRY OUT 3D CHECKS
E SWITCH TEST
B HIGH VOLTAGE TRANSFORMER TEST
CARRY OUT 4R CHECKS
CAUTION Only replace weak point F3 with the correct value replacement
H TEMPERATURE FUSE TF1, TF2, TF3 TEST
F WEAK POINT F3 TEST CARRY OUT 3D CHECKS
G FUSE F1, F2 F10A TEST CARRY OUT 3D CHECKS
M TOUCH CONTROL PANEL ASSEMBLY TEST
3. CARRY OUT 4R CHECKS
J MOTOR WINDING TEST
K NOISE FILTER TEST
N KEY UNIT TEST
O RELAY TEST
TEST PROCEDURES
PROCEDURE
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
TOUCH CONTROL PANEL ASSEMBLY
1 Power Supply Circuit
2 Reset Circuit
11 Stop Switch Circuit
Signal
Power source voltage GND
Temperature measurement input EXHAUST THERMISTOR
Temperature measurement input MAGNETRON THERMISTOR TH2
Signal to sound buzzer
Signal synchronized with commercial power source frequency
Internal clock oscillation frequency setting input
Power source voltage
Digit selection signal
Key strobe signal
Sound Voltage level control terminal
Signal
Figure T-2. Relation between Pin Nos, and Signals
2-2 Memory IC
SERVICING
2. Shapes of Electronic Components
4. Servicing Tools
PROCEDURE FOR CHECKING/CLEARING SERVICE COUNTS OF MICROWAVE OVEN
5. Other Precautions
PROCEDURE FOR ENTERING TO
OTHER CHECKING AND CLEARING PROCE- DURE FOR
PRECAUTIONS FOR USING LEAD-FREE SOLDER
2. Using lead-free wire solder
1. Employing lead-free solder
3. Soldering
COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE
OUTER CASE, REAR CABINET AND POWER SUPPLY CORD REMOVAL
precautions
To remove rear cabinet and power supply cord
MAGNETRON THERMISTOR REPLACEMENT
ASSEMBLY REMOVAL
Re-install
Figure C-1. Magnetron thermistor installation
HOW TO RELEASE THE POSITIVE LOCK CONNECTOR
TERMINAL INSULATOR REPLACEMENT
Procedure
Figure C-2. How to release the positive lock connector
CONTROL PANEL ASSEMBLY AND CONTROL UNIT REMOVAL
POWER SUPPLY CORD REPLACEMENT
CONTROL PANEL ASSEMBLY REMOVAL
HOW TO ATTACH MEMBRANE SWITCH AND GRAPHIC SHEET
INTERLOCK SWITCHES, MONITOR SWITCHES, AND STOP SWITCH REMOVAL
INTERLOCK SWITCHES, MONITOR SWITCHES, AND STOP SWITCH ADJUSTMENT
DOOR REPLACEMENT AND ADJUSTMENT
Figure C-4. Power supply cord replacement
DOOR DISASSEMBLY
RE-INSTALL
Note After any service to the door
DOOR ADJUSTMENT
SERVICE INFORMATION
UPPER AND LOWER LATCH HEADS REMOVAL
DOOR CASE REMOVAL
DOOR GLASS REMOVAL
PREPARATION
PROCEDURE
MICROWAVE MEASUREMENT
Figure O-1 Oven Schematic-OFF Condition
Figure O-2 Oven Schematic-IDLE Condition Door opened condition
SCHEMATIC NOTE CONDITION OF OVEN
SCHEMATIC NOTE CONDITION OF OVEN 1. FOR 1MINUTE AFTER DOOR CLOSED
Figure O-3 Oven Schematic-Cooking Condition
SCHEMATIC NOTE CONDITION OF OVEN 1. DOOR CLOSED
2. MANUAL REPEAT KEY TOUCHED 3. COOKING TIME PROGREMMED
4. START PAD TOUCHED
Figure S-1. Pictrorial Diagram
COMPONENTS
A B C
VOLTAGE
PanelCircuit
Control2
Figure S-3. Printed Wiring Board
BLACK 2.5A FUSE
A B C D E F G H
A B C D E
PARTS LIST
Note The parts marked ∆ may cause undue microwave exposure
The parts marked * are used in voltage more than
ELECTORIC PARTS
OVEN PARTS
REF. NO
DESCRIPTION
CODE
DOOR PARTS
MISCELLANEOUS
SCRE,NUTS AND WASHERS
REF. NO
PACKING AND ACCESSORIES
HOW TO ORDER REPLACEMENT PARTS
1. MODEL NUMBER 2. REF. NO
4. DESCRIPTION
A2 A1
OVEN AND CABINET PARTS
F G H
CONTROL PANEL PARTS
DOOR PARTS
MISCELLANEOUS
3-2-2 3-2-3