R-23GT-F R-24GT-F SERVICE MANUAL S0512R24GTF// COMMERCIAL MICROWAVE OVENS MODELS DOUBLE QUANTITY EXPRESS DEFROST 11 1 12 2 13 3 14 4 15 5 16 6 17 7 18 8 9 19 1800W/R-24GT 20 SELECTATIME SET 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.
R-23GT-F R-24GT-F 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.
R-23GT-F R-24GT-F 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. Don't Touch ! Danger High Voltage When the testing is completed, 1.
R-23GT-F R-24GT-F MICROWAVE MEASUREMENT PROCEDURE A. 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 useful life of the oven), 5 mW/cm2 at any point 5cm or more from the external surface of the oven.
R-23GT-F R-24GT-F SERVICE MANUAL PRODUCT DESCRIPTION COMMERCIAL MICROWAVE OVEN GENERAL INFORMATION R-23GT-F/ R-24GT-F FOREWORD This Manual has been prepared to provide Sharp Electronics Corp. Service Personnel with Operation and Service Information for the SHARP MICROWAVE OVENS, R-23GT-F/ R-24GT-F. 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.
R-23GT-F R-24GT-F SPECIFICATION ITEM DESCRIPTION Power Requirements R-23GT-F: 230/208 Volts 2.5 kW Approx. 13.3 A at 208 V / Approx. 11.9 A at 230 V R-24GT-F: 230/208 Volts 2.9 kW Approx. 14.6 A at 208 V / Approx. 13.
R-23GT-F R-24GT-F VOLTAGE SELECT The oven has been preset for 230V operation. If you need to change this oven for 208V operation, follow instructions below. 1. Unplug oven. 2. Remove one screw(A) from the Voltage Select Cover located on back of the oven near the bottom. 3. Remove the Voltage Select Cover and rotate 180 degrees. 4. Reinstall the Voltage Select Cover using one screw(A) removed in Step 2. 5. Plug power cord into wall outlet.
R-23GT-F R-24GT-F OPERATION DESCRIPTION OF OPERATING SEQUENCE 7. The monitor switch (1) is electrically monitoring the operation of the secondary interlock switch (1) and primary interlock relay (1), and monitor switch (2) is electrically monitoring the operation of the secondary interlock switch (2) and primary interlock relay (2), and monitor switches (1), (2) are mechanically associated with the door so that it will function in the following sequence.
R-23GT-F R-24GT-F TWO MAGNETRON OPERATION SYSTEM OPERATION OF MAGNETRON Two magnetrons (1), (2) are equipped in order to get higher microwave power output. The primary windings of the power transformers (1), (2) are connected so that each magnetron can be oscillated alternatively according to the frequency of the power supply. Refer to the Figure B-1. COMMERCIAL FREQUENCY (60HZ) POWER OUTPUT BY MAGNETRON 1 POWER OUTPUT BY MAGNETRON 2 Figure B-1.
R-23GT-F R-24GT-F SCHEMATIC NOTE: CONDITION OF OVEN 1. FOR 1MINUTE AFTER DOOR OPENED. 2. " . " APPEARS ON DISPLAY. NOISE FILTER PRIMARY INTERLOCK RELAY (1) POWER TRANSFORMER (1) DOOR SENSING SWITCH B3 OL OL SM SM BM BLOWER MOTOR 3300pF STIRRER MOTOR COM VOLTAGE SELECT SWITCH (V.S.SW) (2) MONITOR SWITCH (1) CAPACITOR (1) 0.94µF POWER TRANSFORMER (2) V.S.SW (3) NC B1 OVEN THERMISTOR (1) V.S.
R-23GT-F R-24GT-F DESCRIPTION AND FUNCTION OF COMPONENTS Functions: With the door shut, the contacts of the door sensing switch and the secondary interlock switches (1), (2) are closed and the contacts of the monitor switches (1), (2) are open. 1. When the door is opened, the contact of the door sensing switch and secondary interlock switches (1), (2) are opened first, then the contact of the monitor switches (1), (2) are closed. 2.
R-23GT-F R-24GT-F SELECT SWITCH AND ELECTRICAL COMPONENTS CONDITION OVEN THERMISTOR (2) This thermistor detects temperature of the oven cavity bottom plate. The thermistor is a negative temperature coefficient type. The temperature is detected through the resistance of the thermistor. If the temperature is high, the control will display “EE17” and the oven will stop. SWITCH NO.
R-23GT-F R-24GT-F TROUBLESHOOTING GUIDE Never touch any part in the circuit with your hand or an uninsulated tool while the power supply is connected. When troubleshooting the microwave oven, it is helpful to follow the Sequence of Operation in performing the checks. Many of the possible causes of trouble will require that a specific test be performed. These tests are given a procedure letter which will be found in the "Test Procedure "section.
12 ERROR MODE COOKING CONDITION OFF CONDITION CONDITION PRIMARY INTERLOCK SYSTEM (1), (2) (1) (2) F G MONITOR SWITCH (1), (2) (1) (2) I MONITOR FUSE HIGH VOLTAGE CAPACITOR (1), (2) H.V. RECTIFIER (1), (2) POWER TRANSFORMER (1), (2) MAGNETRON (1), (2) Home fuse blows when power cord is plugged into wall receptacle Monitor fuse blows when power cord is plugged into wall receptacle. " . " does not appear in display when power cord is first plugged into wall receptacle.
R-23GT-F R-24GT-F TEST PROCEDURES PROCEDURE LETTER A COMPONENT TEST MAGNETRON ASSEMBLY TEST 1. 2. 3. 4. 5. 6. 7. 8. 9. Disconnect the power supply cord, and then remove outer case. Open the door and block it open. Discharge two high voltage capacitors. 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.
R-23GT-F R-24GT-F TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 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. (HIGH VOLTAGES ARE PRESENT AT THE HIGH VOLTAGE TERMINAL, SO DO NOT ATTEMPT TO MEASURE THE FILAMENT AND HIGH VOLTAGE.) C HIGH VOLTAGE RECTIFIER (1) AND/ OR (2) TEST 1. 2. 3. 4. 5. 6. 7. 8. Disconnect the power supply cord, and then remove outer case. Open the door and block it open.
R-23GT-F R-24GT-F TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 5. 6. 7. 8. Reconnect all leads removed from components during testing. Reinstall the outer case (cabinet). Reconnect the power supply cord after the outer case is installed. 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 blower motor, stirrer motors and oven light will be activated by RY1. PRIMARY INTERLOCK RELAY (RY2, RY3) 1.
R-23GT-F R-24GT-F TEST PROCEDURES PROCEDURE LETTER I COMPONENT TEST BLOWN MONITOR FUSE TEST 1. 2. 3. 4. Disconnect the power supply cord, and then remove outer case. Open the door and block it open. Discharge two high voltage capacitors. If the monitor fuse is blown when the door is opened, check the primary interlock relays RY2, RY3, secondary interlock switches (1), (2) and monitor switches (1), (2) according to the "TEST PROCEDURE" for those switches before replacing the blown monitor fuse.
R-23GT-F R-24GT-F TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST Room Temp. 59˚F (15˚C) 68˚F (20˚C) 77˚F (25˚C) Resistance Approx. 373 kΩ Approx. 292 kΩ Approx. 231 kΩ If the meter does not indicate above resistance, replace the thermistor. 4-2. OVEN THERMISTOR (1) TEST Disconnect connector-B from the CPU unit. Measure the resistance of the thermistor with an ohmmeter. Connect the ohmmeter leads to the leads of the thermistor. Room Temp. 59˚F (15˚C) 68˚F (20˚C) 77˚F (25˚C) Resistance Approx.
R-23GT-F R-24GT-F TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST Before testing, 1) Disconnect the power supply cord, and then remove outer case. 2) Open the door and block it open. 3) Discharge two high voltage capacitors. 4) Disconnect the leads to the primary of the power transformer. 5) Ensure that these leads remain isolated from other components and oven chassis by using insulation tape. 1. Key Unit. NOTE ; 1) Check Key unit ribbon connection before replacement.
R-23GT-F R-24GT-F TEST PROCEDURES PROCEDURE LETTER N COMPONENT TEST KEY UNIT TEST 1. Disconnect the power supply cord, and then remove outer case. 2. Open the door and block it open. 3. Discharge two high voltage capacitors. 4.
R-23GT-F R-24GT-F TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 13. Reconnect the power supply cord after the outer case is installed. 14. Run the oven and check all function. P FOIL PATTERN ON THE PRINTED WIRING BOARD TEST To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on the PWB, this foil pattern acts as a fuse. 1. Foil pattern check and repairs. 1) Disconnect the power supply cord, and then remove outer case.
R-23GT-F R-24GT-F TOUCH CONTROL PANEL ASSEMBLY OUTLINE OF TOUCH CONTROL PANEL The touch control section consists of the following units as shown in the touch control panel circuit. 15) Oven Cavity Temperature Detecting Circuit This is a circuit for transmitting output change of thermistor (Oven thermistor (2)) to IC1. (1) Control Unit (2) Key Unit 16) High Voltage Monitoring Circuit.
R-23GT-F R-24GT-F VOLTAGE REGULATION FOR "ERROR" INDICATION Voltage regulation Input to 208V Input to 230V *Normal +6% excel. 208.0--220.48 230.0--243.8 *Normal -9% excel. 189.28--208.0 209.3--230.0 *Error.or indication range +6% to +13% excel. -9% to -13% excel. 220.48 235.04 189.28 180.96 243.8 259.9 209.3 200.1 Not cookable over +13% under -13% over 235.04 under 180.96 over 259.9 under 200.1 * Cookable Range 2.
R-23GT-F R-24GT-F DESCRIPTION OF LSI LSI(IZA633DR) The I/O signal of the LSI(IZA633DR) is detailed in the following table. Pin No. 1 Signal VCC I/O IN Description Power source voltage: +5V. VC voltage of power source circuit input. VEE/AVSS IN Connected to GND 4 VREF IN Connected to VC. (+5V) 5 AN7 IN Temperature measurement input: INTAKE THERMISTOR.
R-23GT-F R-24GT-F Pin No. 21 Signal I/O P45 OUT Description Digit selection signal. The relation between digit signal and digit are as follows: Digit signal Digit P42 ..................... 1st. P43 .................... 2nd. P44 ..................... 3rd. P45 ..................... 4th. 25 P44-P42 OUT INT1 IN L +5V P42 GND P43 P44 Normally, one pulse is output in every ß period, and input to the grid of the light-emitting diode. 22-24 H ß(60Hz) P45 Digit selection signal.
R-23GT-F R-24GT-F Pin No. Signal I/O Description 41-48 P17-P10 OUT Segment data signal. Signal similar to P21. 49-56 P07-P00 OUT Segment data signal. Signal similar to P21. 57-59 P37-P35 OUT Terminal not used. 60 P34 OUT Key strobe signal. Signal applied to touch-key section. A pulse signal is input to P27, P26, P25 and P24 terminals while one of G4 line keys on key matrix is touched. 61 P33 OUT Key strobe signal. Signal applied to touch-key section.
R-23GT-F R-24GT-F SERVICING 1. Precautions for Handling Electronic Components 5) Re-connect the power supply cord after the outer case is installed. 6) Run the oven and check all functions. A. On some models, the power supply cord between the touch control panel and the oven itself is so short that the two can’t be separated. For those models, check and repair all the controls (sensor-related ones included) of the touch control panel while keeping it connected to the oven. B.
R-23GT-F R-24GT-F 3) Practice for inputting total using times (Ex. 310000 times). PROCEDURE FOR CHECKING/CLEARING SERVICE COUNTS OF MICROWAVE OVEN ... Flashing / PAD (Door close) The following procedure enables the servicer to obtain the total using times (cook cycles) since the microwave oven is purchased and the total operation time (hours) since the microwave oven is purchased. The maximum capacity of the total using is 999,999 times, and the maximum capacity of total operation time is 999,999 hours.
R-23GT-F R-24GT-F 5) Practice for cancelling total using times and total operation time (user and service) and all other counter. ... Flashing / PAD (Door close) SET SET (within 2.0sec.) DOUBLE QUANTITY CHECK SINGLE SET KEY INDICATOR 1 1 After 10% of total cooking time is passed : : : 9 9 After 90% of total cooking time is passed START A There is no pause TONE 2) To check the constants of Express defrost.
R-23GT-F R-24GT-F MEMORY READJUSTMENT PROCEDURE 1. To set the standard voltage When the IC2 is changed in the control unit, the standard voltage must be set again for power supply check. The power supply must be set 230V within ± 1V, and 230V connector in control unit installed. PAD ORDER (230V power) (Door close) (Plug in) SIGNAL DOUBLE SET DISPLAY TONE (BLANK) . . . . CHECK 0633 (plug off) (BLANK) All indicators ON NOTE : 1. This procedure must be performed within 1 minute. 2.
R-23GT-F R-24GT-F 2]. [JUDGMENT PROCEDURE FOR UPPER MAGNETRON AND ITS CIRCUIT] Disconnect the power supply cord. Disconnect lead wires to the interlock relay RY3 to avoid operation of lower magnetron circuit. Reconnect power supply Heating for one minute. No Temperature of the water increased? *1 If EE1 is indicated, carry out Test procedures A-J and find out the defective part. Upper magnetron, its driving circuit or any parts on its circuit may be defective. Yes EE2 should be indicated.
R-23GT-F R-24GT-F COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE WARNING AGAINST HIGH VOLTAGE: Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may result in severe, possibly fatal, electric shock. (Example) High Voltage Capacitor, Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc.. WARNING: Avoid possible exposure to microwave energy. Please follow the instructions below before operating the oven. 1.
R-23GT-F R-24GT-F POWER TRANSFORMERS (1) AND/OR (2) REMOVAL 1. Disconnect the power supply cord and then remove outer case and rear cabinet, referring to "OUTER CASE, REAR CABINET AND POWER SUPPLY CORD REMOVAL". 2. Open the oven door and block it open. 3. Discharge two high voltage capacitors. 4. Disconnect wire leads of power transformers (1) and/or (2) from magnetrons (1) and/or (2). 5. Remove the wire leads of power transformers from the wire holder. 6.
R-23GT-F R-24GT-F HIGH VOLTAGE CAPACITOR AND HIGH VOLTAGE RECTIFIER ASSEMBLY REMOVAL 1. Disconnect the power supply cord and then remove outer case and rear cabinet , referring to "OUTER CASE, REAR CABINET AND POWER SUPPLY CORD REMOVAL". 2. Open the oven door and block it open. 3. Discharge two high voltage capacitors. 4. Remove two (2) screws holding ground side terminals of high voltage rectifier assembly to the capacitor holder and oven cavity. 5.
R-23GT-F R-24GT-F CONTROL PANEL ASSEMBLY AND CONTROL UNIT REMOVAL CONTROL PANEL ASSEMBLY REMOVAL upward. 12.Now, the control unit and control panel frame (with key) are free. The complete control panel should be removed for replacement of components. To remove the control panel, proceed as follows: 1. Disconnect the power supply cord. 2. Remove the air intake filter assembly from the base plate. 3. Remove two (2) screws holding the control panel to the base plate. 4.
R-23GT-F R-24GT-F procedure. DOOR SENSING SWITCH Push the two (2) tabs outward and pull switch forwards to release switch. MONITOR SWITCHES OR SECONDARY INTERLOCK SWITCHES Remove one (1) screw and nut holding two switches together to latch hook. 8. Now, switch(es) is now free. of the latch hook. 2) Fasten both switches together to latch hook with one (1) screw and nut. SECONDARY INTERLOCK SWITCHES 1) Mount the two (2) switches side by side in the middle position of the latch hook.
R-23GT-F R-24GT-F Note: After any service to the door; (A) Make sure that door sensing switch, secondary interlock switches (1), (2) and monitor switches (1), (2) are operating properly. (Refer to chapter "Test Procedures".). (B) An approved microwave survey meter should be used to assure compliance with proper microwave radiation emission limitation standards. This function does not require that door be air-tight, moisture (condensation)-tight or light-tight.
1 2 RED 3 37 R E D RED BLK BLK BLK BLK RED IC RY3(2) TAB2 TAB1 C N I A T1 RY1 7 2 3 4 5 6 1 3 BRN RED YLW BLK CN-A WHT CN-H 1 RED 2 BLU 4 BLK GRN COM 5 BLK WHT GRY NO Blue case Blue case 1 RED 2 3 WHT (2) SECONDARY INTERLOCK SWITCH (2) (OVEN SIDE) Blue case ORG GRY COM Blue case E G 6 R E D G R Y B R N Figure S-1.
TB2 TB1 COM NC COM NC A1 A7 b VRS1 CT1 RY3 RY2 c a d RY1 – – + 5 D22 VC Q3 KRC101M 6 C70 C61 R32 2.7k B1 B2 D23 10EDB10 R70 4.7k DOOR SWITCH VC VC SP1 R40 2.7k (J3) (A) (J4) ZD2 HZ4A2 R5 4.7k 20k (J6) R3 4.7k VC H1 C5 – MAGNETRON THERMISTOR ON 60 55 50 45 40 35 33 5 10 15 20 25 30 32 P30 P31 P32 P33 P34 P35 P36 P37 P00 P01 P02 P03 P04 P05 P06 P07 P10 P11 P12 P13 P14 P15 P16 P17 P20 P21 P22 P23 P24 P25 P26 P27 IC3 R83 4.7k R82 4.7k R81 4.
TB2 TB1 COM NC COM NC A1 A7 b VRS1 CT1 RY3 RY2 c a d RY1 – – + 5 D22 VC Q3 KRC101M H 6 C70 C61 R32 2.7k B1 B2 D23 10EDB10 R70 4.7k DOOR SWITCH VC VC SP1 R40 2.7k (J3) (A) (J4) ZD2 HZ4A2 R5 4.7k 10k (J6) R3 4.7k VC H1 C5 – MAGNETRON THERMISTOR ON 60 55 50 45 40 35 33 5 10 15 20 25 30 32 P30 P31 P32 P33 P34 P35 P36 P37 P00 P01 P02 P03 P04 P05 P06 P07 P10 P11 P12 P13 P14 P15 P16 P17 P20 P21 P22 P23 P24 P25 P26 P27 IC3 R83 4.7k R82 4.7k R81 4.
R-23GT-F R-24GT-F 1 2 4 3 1 5 6 13 DIP A A F 8 C30 R5 B + + R33 R32 R31 5 4 Q60 - CF1 32 33 B C5 C6 ZD2 40 3 25 R3 C7 1 E B Q2 3 2 1 16 CN-D 15 IC3 20 50 1 IC1 CN-G 4 C 5 12 C IC2 C31 E R83 C83 R82 C82 R81 C81 R80 C80 R58 R57 R56 R55 R54 R53 R52 R51 B 1 R30 R50 9 6 5 (J3) (J4) 1 64 R62 C3 3 B SP1 10 (J9) Q22 R102 D21 E MICRO 1 D101 C63 R40 (C10) E B RY2 Q23 E + C100 + - D100 14 B C1 11 TB2 E R100 16 (ZD1) Q1 - D2
R-23GT-F R-24GT-F PARTS LIST Note: The parts marked “∆” may cause undue microwave exposure. The parts marked “*” are used in voltage more than 250V. REF. NO. PART NO.
R-23GT-F R-24GT-F REF. NO. D20-22 D23 D70 D100-101 IC1 IC2 IC3 LED1 Q1 Q2 Q3 Q20 Q21 Q22-23 Q60 R1-2 R3-5 R30 R31 R32 R33 R40 R50-58 R60 R61 R62 R63 R64 R65 R66 R70-71 R80-88 R100 R101 R102 (J5) (J5) (J6) (J6) RY1 RY2-3 SP1 T1 CT1 VRS1-2 ZD1 ZD2 3- 2 3- 2-1 3- 2-2 3- 2-3 3- 3 3- 4 3- 5 3- 6 PART NO.
R-23GT-F R-24GT-F ∆ REF. NO. 4-18 4-19 4-19 4-20 4-21 4-22 4-23 4-24 4-25 4-26 4-27 4-28 4-29 4-30 4-31 4-32 4-33 4-34 4-35 4-36 4-37 4-38 4-39 4-40 4-41 4-42 4-43 4-44 4-45 4-46 4-47 4-48 PART NO.
R-23GT-F R-24GT-F REF. NO. PART NO.
R-23GT-F R-24GT-F 2 1 4 3 6 5 OVEN AND CABINET PARTS 7-19 4-20 6-8 A 7-22 2-5-2 6-11 A 4-23 2-6 2-5-1 7-9 4-30 7-22 2-4 7-22 4-33 1-6 6-12 2-5 4-43 7-22 7-22 B 7-15 7-22 B 7-22 2-8 7-21 7-22 2-7 4-26 7-22 7-20 7-22 4-2 1-7 1-13 4-38 7-1 4-47 7-14 1-15 7-8 4-12 1-14 4-13 7-14 4-29 1-6 7-13 4-40 B 7-16 A2 A1 7-6 1-7 B A1 A2 7-6 4-1 4-37 4-28 7-8 4-21 4-46 7-23 x-2 7-21 C 1-10 4-27 4-25 7-22 4-18 7-22 1-10 C D 4-45 7-14 4-3 4-24 7-21 7-3
R-23GT-F R-24GT-F 2 1 4 3 6 5 3-2 CONTROL PANEL PARTS 3-1 3-2-3 A A 6-15 3-4 3-2-2 B B 3-5 5 DOOR PARTS 3-6 3-3 C C 5-4 3-2-1 5-12 5-14 D 5-13 D 5-1 5-13 5-15 5-8 5-6 E 5-18 5-16 5-13 E 5-17 5-9 5-7 6-3 MISCELLANEOUS F F 5-6 5-10 5-13 5-3 5-2 5-20 5-19 5-11 G G 5-10 6-4 5-5 To power transformer To high voltage capacitor 6-7 Actual wire harness may be different from illustration.