R-90GC SERVICE MANUAL S7212R90GC/// HIGH SPEED CONVECTION MICROWAVE OVEN MODEL R-90GC 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.
R-90GC 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-90GC 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-90GC 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-90GC SERVICE MANUAL PRODUCT DESCRIPTION HIGH SPEED CONVECTION MICROWAVE OVEN GENERAL INFORMATION R-90GC FOREWORD This Manual has been prepared to provide Sharp Electronics Corp. Service Personnel with Operation and Service Information for the SHARP HIGH SPEED CONVECTION MICROWAVE OVEN, R-90GC. OPERATION TROUBLESHOOTING GUIDE AND TEST PROCEDURE 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-90GC SPECIFICATION ITEM DESCRIPTION Power Requirements 240 Volts 7.5 Amperes (Microwave) / 13.0 Amperes (Convection)/ 13.5 Amperes (Speed Cooking) 60 Hertz / Single phase, 3 wire grounded Power Output 1000 watts (IEC Test Procedure) Operating frequency of 2450MHz Top Heater Power Output 1700 Watts Side Heater Power Output 1200 Watts Case Dimensions Width 21-5/8" Height 16" Depth 24-5/8" Cooking Cavity Dimensions (1.
R-90GC Extension Cord Receptacle Box Cover If it is necessary to use an extension cord, use only a 3-wire extension cord that has a 3-blade grounding plug and a 3-slot receptacle that will accept the plug on the high speed oven. The marked rating of the extension cord should be AC 240 volt, 15 amp. or more. Be careful not to drape the cord over the countertop or table where it can be pulled on by children or tripped over accidentally.
R-90GC OPERATION DESCRIPTION OF OPERATING SEQUENCE The following is a description of component functions during oven operation. 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.
R-90GC motor and convection motor are turned on. 2. The coil of relay (RY4) is energized by the control unit. The damper is moved to the closed position, closing the damper switch contacts. The closing of the damper switch contacts sends a signal to the LSI on the control unit de-energizing the relay (RY4) and opening the circuit to the damper motor. 3. The solid-state relays are energized by the control unit and the main supply voltage is applied to the top and side heating elements. 4.
R-90GC time. And the oven will cook according to the special cooking sequence. measurement circuit is sampled by the LSI and twenty five (25) seconds after the thermistor is cut off the LSI turns on the convection fan for three (3) seconds. 3. The above procedure is repeated.
R-90GC SCHEMATIC NOTE: CONDITION OF OVEN 1. DOOR CLOSED. 2. COOKING TIME PROGRAMMED. 3. “START” PAD TOUCHED. MAGNETRON CAPACITOR 1µ AC 2300V H.V. RECTIFIER MONITOR SWITCH TTM OL CONVECTION MOTOR CAPACITOR TURNTABLE MOTOR OVEN LAMP COM. SOLID-STATE RELAY COM.
R-90GC SCHEMATIC NOTE: CONDITION OF OVEN 1. DOOR CLOSED. 2. GRILL PAD TOUCHED. 3. COOKING TIME PROGRAMMED. 4. “START” PAD TOUCHED. MAGNETRON CAPACITOR 1µ AC 2300V H.V. RECTIFIER MONITOR SWITCH TOP HEATIMG ELEMENT TTM OL OVEN LAMP CONVECTION MOTOR CAPACITOR TURNTABLE MOTOR COM. SOLID-STATE RELAY COM.
R-90GC DESCRIPTION AND FUNCTION OF COMPONENTS DOOR OPEN MECHANISM secondary interlock switch contacts fail to open, the monitor fuse blows simultaneously with closing of the monitor switch contacts. The door is opened by pulling the door handle down and forward, referring to the figure D-1. When the door handle is pulled down, the latch heads are moved upward. And then when the door handle is pulled forward, the latch heads are released from the latch hooks right and left. Now, the door will open.
R-90GC open at 302˚F (150˚C) causing the oven to shut down. When the thermal cut-out has cooled, the thermal cut-out closes at 266˚F (130˚C). tion time reaches 0, the heating elements are de-energized and the convection fan stops operating and the oven shuts off. Flow of hot air: The rotation direction of the convection motor is controlled by relay RY6. When the convection fan rotates clockwise, the hot air from the oven cavity left side wall blows stronger than one from the oven cavity top wall.
R-90GC control unit and shut-off relay (RY4) is turned off. 1-5. The 240 volts A.C. to the damper motor is removed and the motor turns off. 2. When oven is microwave cooking: Damper is in the open position. 3. When oven is convection cooking: 3-1. Damper motor is energized by touching the convection, temperature and START pads. 3-2. When damper is in the closed position (damper switch is ON), its signal is sensed by the control unit, and shut-off relay (RY4) is de-energized. 3-3.
A B C D E F G H J K M O P Q U V W W W W W W Y Z X X Replace Replace Replace Check S Check Check Check L N Replace POSSIBLE CAUSE AND DEFECTIVE PARTS U I MAGNETRON POWER TRANSFORMER H.V.
R-90GC TEST PROCEDURES PROCEDURE LETTER A COMPONENT TEST MAGNETRON ASSEMBLY TEST 1. 2. 3. 4. 5. 6. Disconnect the power supply cord. Remove the outer case cabinet, referring to “OUTER CASE CABINET REMOVAL”. Open the oven door and block it open. Discharge the high voltage capacitor. Remove the back plate from the oven, referring to “BACK PLATE REMOVAL”. To test for an open filament, isolate the magnetron from the high voltage circuit.
R-90GC TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST transformer because the primary coil (thermostat) has opened. An open primary coil (thermostat) indicates overheating of the power transformer. Check for restricted air flow to the power transformer, especially the fan motor (power transformer side). 8. Reconnect all leads removed from components during testing. 9. Reinstall the outer case (cabinet) and the back plate. 10.
R-90GC TEST PROCEDURES PROCEDURE LETTER F COMPONENT TEST PRIMARY INTERLOCK SYSTEM TEST DOOR SENSING SWITCH 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. Discharge high voltage capacitor. Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO) terminal of the switch. The meter should indicate an open circuit with the door open and a closed circuit with the door closed.
R-90GC TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST RELAY, SECONDARY INTERLOCK SWITCH, DOOR SENSING SWITCH AND MONITOR SWITCH FOR PROPER OPERATION. If the monitor fuse is blown by improper switch operation, the monitor fuse and monitor switch must be replaced with "monitor fuse and monitor switch assembly" part number FFS-BA033WRKZ, even if the monitor switch operates normally. The monitor fuse and monitor switch assembly is comprised of a 20 ampere fuse and switch. 5.
R-90GC TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST CAUTION: IF THE THERMAL CUT-OUT INDICATES AN OPEN CIRCUIT AT ROOM TEMPERATURE, REPLACE THERMAL CUT-OUT. L THERMAL CUT-OUT (SIDE HEATER) 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. Discharge high voltage capacitor.
R-90GC TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 3. 4. 5. 6. Open the oven door and block it open. Discharge the high voltage capacitor. Remove the back plate from the oven, referring to “BACK PLATE REMOVAL”. Disconnect connector-E from the control unit. Measure the resistance of the thermistor with an ohmmeter. Connect the ohmmeter leads to Pin No’s E-5 and E-6. Room Temperature 68˚F(20˚C) - 86˚F(30˚C) Resistance Approx. 360 kΩ - 152 KΩ 7.
R-90GC TEST PROCEDURES PROCEDURE LETTER R COMPONENT TEST CONVECTION MOTOR CAPACITOR TEST 1. 2. 3. 4. 5. 6. 7. 8. S Disconnect the power supply cord, and then remove outer case. Open the door and block it open. Discharge high voltage capacitor. Disconnect input leads and check for short or open between the terminals using an ohmmeter.
R-90GC TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST In this service manual, troubleshooting by unit replacement is described according to the symptoms indicated. Before testing, 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 these leads remain isolated from other components and oven chassis by using insulation tape. 1.
R-90GC TEST PROCEDURES PROCEDURE LETTER W COMPONENT TEST RELAY TEST 1. 2. 3. 4. 5. Disconnect the power supply cord, and then remove outer case. Open the door and block it open. Discharge high voltage capacitor. Disconnect the leads to the primary of the power transformer. Ensure that these leads remain isolated from other components and oven chassis by using insulation tape. 6. After that procedure, re-connect the power supply cord. 7. Remove the outer case and check voltage between Pin Nos.
R-90GC TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST arrows. And touch the number pad 5. And then touch the start pad. (3) The oven is in Compu Defrost cooking condition. (4) The oven will operate as follows. WEIGHT Steaks/Chops 0.5lbs 1ST STAGE LEVEL TIME 70% 17sec. 2ND STAGE 3RD STAGE LEVEL TIME LEVEL TIME 60% 30sec. 30% 45sec. (5) If improper operation is indicated, the control unit is probably defective and should be checked.
R-90GC 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. 5) Buzzer Circuit The buzzer is responds to signals from the LSI to emit noticing sounds (tact switch touch sound and completion sound). 6) Temperature Measurement Circuit : (OVEN THERMISTOR) The temperature in the oven cavity is sensed by the thermistor.
R-90GC Pin No. Signal I/O 5 AN1 OUT 6 AN0 OUT 7 AN15 IN AN14-AN12 AN11 IN IN 12 AN10 IN 13 AN9 IN 14 AN8 IN Relay operation watching terminal. The LSI is watching so that the three (3) relays for the top heating element, the side heating element and the power transformer do not operate at the same time. 15 P83 OUT 16 P82 OUT Timing signal output terminal for temperature measurement(OVEN THERMISTOR). “L” level (-5V) : Thermistor OPEN timing.
R-90GC Pin No. 26 27 28 Signal I/O P76 OUT P75 P74 OUT OUT 29 P73 OUT 30 31 P72 P71 OUT IN Description Magnetron high-voltage circuit driving signal. To turn on and off the cook relay(RY2). In P-HI operation, the signals holds “L” level during microwave cooking and “H” level while not cooking. In other cooking modes (P-90, P-80, P-70, P-60, P-50, P-40, P-30, P-20, P-10, P-0) the signal turns to “H” level and “L” level in repetition according to the power level.
R-90GC Pin No. Signal I/O 90 91 PB6 PB5 OUT OUT 92 PB4 OUT PB3-PB0 AVSS IN IN 98 VREF IN 99 AN7 OUT 100 AN6 OUT 93-96 97 Description Terminal not used. LED driving signal. Signal is applied to the light-emitting diodes (LD1, LD2, LD3, LD5, LD7, LD9 and LD11). LED driving signal. Signal is applied to the light-emitting diodes (LD4, LD6, LD8 and LD10). Signal coming from tact switch. A/D converter power source voltage. The power source voltage to drive the A/D converter in the LSI.
R-90GC 4. Servicing Tools panel while keeping it apart from the oven proper; in this case you must short both ends of the door sensing switch (on PWB) of the touch control panel with a jumper, which activates an operational state that is equivalent to the oven door being closed. As for the sensor-related controls of the touch control panel, checking them is possible if dummy resistor(s) with resistance equal to that of the controls are used. Tools required to service the touch control panel assembly.
R-90GC 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-90GC CAUTION 1. DISCONNECT THE OVEN FROM THE POWER SUPPLY BEFORE REMOVING THE OUTER CASE CABINET. 2. DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPONENTS OR WIRING. NOTE When replacing the outer case cabinet, the two (2) special Torx screws must be reinstalled in the same locations. Special screw Screw Driver (Type: TORX T20 H or GTXH20-100) Figure C-1. Special screw postion TERMINAL INSULATOR REPLACEMENT Installation 1. Insert the receptacle into terminal insulator. 2.
R-90GC 8. Remove the two (2) screws holding the transformer mounting angle to the bottom plate from under the bottom plate. 9. Remove the two (2) screws holding the transformer mounting angle to the bottom plate from the top of the bottom plate. 10.Remove the four (4) screws holding the power transformer to the transformer mounting angle. 11.Now, the power transformer is free. MAGNETRON REMOVAL 1. Disconnect the power supply cord. 2.
R-90GC SOLID-STATE RELAY (MAGNETRON SIDE) REMOVAL 1. Disconnect the power supply cord. 2. Remove the outer case cabinet, referring to “OUTER CASE CABINET REMOVAL”. 3. Open the oven door and block it open. 4. Discharge the high voltage capacitor. 5. Remove the back plate from the oven, referring to “BACK PLATE REMOVAL”. 6. Disconnect the wire leads and the connector from the solid-sate relay. 7. Release the main wire harness from the hole of the magnetron separator. 8.
R-90GC bottom plate. 30.Remove the thirteen (13) screws holding the convection duct to the oven cavity and the heater duct upper. 31.Remove the convection duct assembly from the oven cavity. 32.Now, the convection duct assembly is free. 33.Remove the nine (9) screws holding the heater duct upper to the oven cavity. 34.Remove the heater duct upper from the oven cavity. 35.Now, the heater duct upper assembly is free.
R-90GC 3. 4. 5. 6. Open the oven door and block it open. Discharge the high voltage capacitor. Disconnect the wire leads from the switch. Remove the one (1) screw holding the latch hook (right or left) to the oven cavity front plate, and release the latch hook (right or left). 7. Keep pushing the stopper tub holding the switch to the latch hook (right or left) and revolve the switch on the pole. 8. Remove the switch from the latch hook (right or left). 9. Now, the switch is free. Reinstallation 1.
R-90GC 5. Close the door. 6. Remove the two (2) door springs from the door cam right, oven hinge right, door com left and oven hinge left. 7. Release the door cams right and left from the right and left door cam pins of the door. 8. Remove the door cams right and left from the oven cavity front plate. 9. Open the door assembly at an angle of more than 90˚ with the oven cavity front plate. 10.
R-90GC CHOKE COVER 22.Pull out the two (2) handle pins from the two (2) handle levers. 23.Remove the two (2) handle levers from the door panel. 24.Now, the door panel is free. 8. Insert a putty knife (thickness of about 0.5 mm) into the gap between the choke cover and the door panel assembly as shown in Figure C-5. 9. Lift up the choke cover. 10.Now, the choke cover is free from the door panel assembly.
H 1 2 3 38 TOUCH CONTROL TRANSFORMER CN-D 4 6 1 5 1 COM. RY2 R E D D 1 BLK 2 3 RED 4 5 ORG 1 RED 2 GRN 3 BLU 4 BRN 5 BLK 6 WHT 5 6 BLK 3 BLK WHT 1 WHT RED 2 RED R E D 3 1 4 2 POWER SUPPLY CORD 120V 60Hz CONVECTION MOTOR THERMISTOR BLK 2 WHT 1 R E D RED BLK WHT WHT SIDE HEATING ELEMENT WHT WHT BLK GRN MONITOR FUSE F20A ORG SIDE HEATER THERMAL CUT-OUT NOTE: The grounding conductor of the power supply cord has been grounded by power supply cord fixing screw.
R-90GC 2 1 4 3 6 5 A A T1 A-2 G-3 VN G-4 VF G-5 VEE H-6 VC G-1 VS H-13 INT H-7 BZ TURN OVER FAN MOTOR DAMPER MOTOR CONVECTION MOTOR A-1 D5 D3 A-4 B + - C9 D1-D4 1N4002L x4 100u 10V R6 6.8 1W D-1 1W RY6 D-5 0.1u/50V 0.01u/50V KIA79L5P R11 1.5K 1/4W H-2 H-5 E-5 DAMPER MOTOR E-3 CONVECTION MOTOR E-1 H-4 D11 RY5 FAN MOTOR H-3 (J2) D16 D15 RY2 R16 3.
B-1 2 A-6 DOOR (B) DAMPER SWITCH Q13 Q11 Q10 POWER B-8 TRANSFORMER + Q12 B-1 0 B-1 1 B-1 B-6 AN0 R15 (15K) - B-9 SIDE HEATING ELEMENT TOP HEATING ELEMENT VC COM OVEN LAMP TURNTABLE MOTOR DOOR (A) THERMISTOR A-7 B-1 3 INT A-1 VS A-2 WATCH C1 WH-B 13pin Harness D50 R50 LD1 AN8 15K R31 P76 AN1 AN9 P77 330F R41 15K R21 AN2 SW24 450˚F SW23 325˚F AN10 AN3 AN11 SW22 425˚F SW21 300˚F 400˚F SW19 275˚F P75 P7 ZD10 HZ20-1 Q1 KRA117M AN4 P74 Q40 3.
R-90GC 2 1 4 3 6 5 A A B B C 1G 2G 3G 4G 5G 6G 1a 1a 1a 1a 1a 1a 7G 1a col1 D 2a 3a 3a Dp2 S2 10G 1a 1a 2a 2a 2a Dp2 3a 3a 3a Dp2 S8 S9 C col2 2a 2a 2a 2a 2a 3a 3a 3a 3a 3a S5 S6 S7 Dp3 S1 9G 1a col1 col2 2a 8G Dp2 Dp3 Dp3 S3 S4 D a h j f E k b E g r n e p c d [ 1G - 10G ] F F G G H H Figure S-4.
SW7 SW3 SW4 SW6 WH-C SW5 1 6 SW2 SW1 1 6 SW9 SW8 1 LD8 LD9 LD4 SW10 LD11 LD6 LD5 SW13 RY1 R11 SW14 JP5 JP2 JP4 78 Q50 Q51 6 E C B 8 73 E C B C75 R75 JP9 JP10 76 1 IC2 4 R76 R71 5 R77 C6 SCL JP6 JP7 JP8 JP12 JP13 JP14 DG1 R70 42 JP17 JP16 45 34 40 JP20 DIP CF1 SW16 R2 SW15 JP22 5 SW18 JP30 SW17 RY5 R10 RY4 SP1 SW20 Q40 B C E JP34 SW19 1 C1 CNE SW22 JP41 SW21 3 RY3 R20 C2 SW24 SW23 C15 C30 C20 R30 RY2 13 B LD2
R-90GC 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-90GC REF. NO. RY6 SP1 VRS1 3-2 3-2-1A 3-2-1B 3-2-1C 3-2-1D 3-2-1E C1 C2 C3 C5 C6 C10 C15 C20 C30 C40 C75 CF1 D50-57 IC-1 IC-2 LD1-11 Q1 Q10-18 Q40 Q50-51 JA JB R1-4 R15 R20 R21 R30 R31 R40 R41 R42 R50-60 R70 R71 R75 R76 R77 ZD1 SW1-30 3- 3 3- 3-1 3- 3-2 3- 3-3 3- 4 3- 5 3- 6 3- 7 3- 8 PART NO.
R-90GC ∆ ∆ ∆ REF. NO. 4-16 4-17 4-18 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 4-49 4-50 4-51 4-52 4-53 4-54 4-55 4-56 4-57 4-58 4-59 4-60 4-61 4-62 4-63 4-64 4-65 4-66 PART NO.
R-90GC REF. NO. 5-22 5-23 PART NO.
G H 1 2 3 47 6-13 1-13 4-37 1-4 7-2 x4 4 7-2 5 4-52 6-15 1-7 7-7 4-23 7-19 7-2 4-9 4-8 4-38 7-4 4-33 4-34 1-19 4-18 4-22 x2 1-1 4-43 4-47 7-12 2-3 7-4 2-2 4-41 4-29 7-12 7-17 7-12 7-11 x4 1-24 7-2 7-4 7-12 6 7-12 7-12 x4 4-2 3-1 4-54 7-4 x2 7-12 7-12 7-5 1-13 7-17 x2 4-53 1-23 7-5 7-12 7-18 x3 1-6 4-17 4-54 6-17 7-3 7-7 4-58 7-10 1-22 4-46 7-12 2-3 7-12 7-15 4-51 4-49 7-12 7-2 7-12 x3 1-5 4-19 4-20 4-48 7-2 4-66 7-6 7-6 7-
R-90GC 2 1 4 3 6 5 3-7 3-2 x7 3-7 x7 CONTROL PANEL PARTS A A 3-7 x8 3-7 3-2-1C B B 3-3-3 x7 3-2-1D 3-6 3-3 3-8 3-7 C C 3-5 3-3-1 DOOR PARTS 3-4 3-3-2 5-21 5-14 5-21 D 5-23 5-3 5-17 5-13 5-5 5-21 5-22 D 5-14 5-17 5-6 5-19 5-4 5-5 E E 5-1 5-2 5-21 5-3 5-4 5-16 5-22 5-20 5-11 5-20 F F x2 5-20 5-10 5-20 x10 5-12 5-20 x2 5-18 G 5-23 G 5-10 5-15 5-7 H H 5-9 5-8 1 2 4 3 48 5 6
R-90GC 2 1 4 3 6 5 MISCELLANEOUS A A 6-1 6-9 6-10 6-16 B B 6-2 Actual wire harness may be different than illustration.
R-90GC COPYRIGHT © 2002 BY SHARP CORPORATION ALL RIGHTS RESERVED. No part of this publication may be reproduced, stored in retrieval systems, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of the publisher. '02 SHARP CORP. (7S1.700E) Printed in U.S.