Service Manual
Page 1
... PERSONNEL: Microwave ovens contain circuitry capable of user-safety the oven should be used . CHECK EXPRESS DEFROST MINUTE PLUS MODEL R-204EWA POWER LEVEL STOP CLEAR TIMER CLOCK In the interest of producing very high voltage and current, contact with following parts may result...18 COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE 22 PICTORIAL DIAGRAM ...28 CONTROL PANEL CIRCUIT ...29 PARTS LIST ...31 PACKING AND ACCESSORIES ...32 SHARP CORPORATION This document has been published to those specified should be restored to its original condition and only parts identical to be used...
... PERSONNEL: Microwave ovens contain circuitry capable of user-safety the oven should be used . CHECK EXPRESS DEFROST MINUTE PLUS MODEL R-204EWA POWER LEVEL STOP CLEAR TIMER CLOCK In the interest of producing very high voltage and current, contact with following parts may result...18 COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE 22 PICTORIAL DIAGRAM ...28 CONTROL PANEL CIRCUIT ...29 PARTS LIST ...31 PACKING AND ACCESSORIES ...32 SHARP CORPORATION This document has been published to those specified should be restored to its original condition and only parts identical to be used...
Service Manual
Page 2
... should be performed on all ovens to be instructed not to use the unit until the oven has been brought into compliance. R-204EWA 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 , 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 proper alignment, integrity, and connections. (d) Any defective or misadjusted components in the interlock, ...
... should be performed on all ovens to be instructed not to use the unit until the oven has been brought into compliance. R-204EWA 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 , 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 proper alignment, integrity, and connections. (d) Any defective or misadjusted components in the interlock, ...
Service Manual
Page 3
... functions. Reconnect all functions. Disconnect the power supply cord, and then remove outer case. 2. It may result in this event, 1. Danger High Voltage Before Servicing 1. R-204EWA WARNING TO SERVICE PERSONNEL Microwave ovens contain circuitry capable of producing very high voltage and current, contact with the use of cold water on the...
... functions. Reconnect all functions. Disconnect the power supply cord, and then remove outer case. 2. It may result in this event, 1. Danger High Voltage Before Servicing 1. R-204EWA WARNING TO SERVICE PERSONNEL Microwave ovens contain circuitry capable of producing very high voltage and current, contact with the use of cold water on the...
Service Manual
Page 4
..., not faster than 4mW/cm2. NOTE: After servicing, record data on the meter. 3) Check for the maximum indication on service invoice and microwave leakage report. 2 R-204EWA MICROWAVE MEASUREMENT PROCEDURE A. Leakage test: Closed-door leakage test (microwave measurement) 1) Grasp the probe of the survey instrument and hold it perpendicular to boil before...
..., not faster than 4mW/cm2. NOTE: After servicing, record data on the meter. 3) Check for the maximum indication on service invoice and microwave leakage report. 2 R-204EWA MICROWAVE MEASUREMENT PROCEDURE A. Leakage test: Closed-door leakage test (microwave measurement) 1) Grasp the probe of the survey instrument and hold it perpendicular to boil before...
Service Manual
Page 5
It is not any other visible damage with Operation and Service Information for the SHARP MICROWAVE OVEN, R-204EWA. Servicing and repair work must be qualified to avoid electrical shock and microwave radiation hazard. All the parts marked "∆"...carefully study the entire text of this manual so that they are used at voltages more than 250V. SHARP ELECTRONICS CORPORATION SHARP PLAZA, MAHWAH, NEW JERSEY 07430-2135 3 R-204EWA PRODUCT DESCRIPTION GENERAL INFORMATION OPERATION TROUBLESHOOTING GUIDE AND TEST PROCEDURE TOUCH CONTROL PANEL COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ...
It is not any other visible damage with Operation and Service Information for the SHARP MICROWAVE OVEN, R-204EWA. Servicing and repair work must be qualified to avoid electrical shock and microwave radiation hazard. All the parts marked "∆"...carefully study the entire text of this manual so that they are used at voltages more than 250V. SHARP ELECTRONICS CORPORATION SHARP PLAZA, MAHWAH, NEW JERSEY 07430-2135 3 R-204EWA PRODUCT DESCRIPTION GENERAL INFORMATION OPERATION TROUBLESHOOTING GUIDE AND TEST PROCEDURE TOUCH CONTROL PANEL COMPONENT REPLACEMENT AND ADJUSTMENT PROCEDURE ...
Service Manual
Page 6
... pad STOP/CLEAR pad, START pad Yes UL Listed. WARNING: Improper use of the grounding plug can result in accordance with a three prong grounding plug. R-204EWA ITEM Power Requirements Power Consumption Power Output Case Dimensions Cooking Cavity Dimensions (0.8 Cubic feet) Control Complement Oven Cavity Light Safety Standard PRODUCT DESCRIPTION SPECIFICATIONS DESCRIPTION...
... pad STOP/CLEAR pad, START pad Yes UL Listed. WARNING: Improper use of the grounding plug can result in accordance with a three prong grounding plug. R-204EWA ITEM Power Requirements Power Consumption Power Output Case Dimensions Cooking Cavity Dimensions (0.8 Cubic feet) Control Complement Oven Cavity Light Safety Standard PRODUCT DESCRIPTION SPECIFICATIONS DESCRIPTION...
Service Manual
Page 7
... or tripped over a longer cord. Wave guide cover 11. If the extension cord must be used, it can be a 3-wire, 15 amp. Safety door latches 3. R-204EWA 15 or 20 amp. Turntable motor shaft 6. fused electrical supply. Oven door with a properly grounded three-pronged wall receptacle or have it is not in...
... or tripped over a longer cord. Wave guide cover 11. If the extension cord must be used, it can be a 3-wire, 15 amp. Safety door latches 3. R-204EWA 15 or 20 amp. Turntable motor shaft 6. fused electrical supply. Oven door with a properly grounded three-pronged wall receptacle or have it is not in...
Service Manual
Page 8
... read-out displays the time still remaining in , 120 volts A.C. Microwave power operation is set the clock, you must first touch the STOP/CLEAR pad. R-204EWA OPERATION DESCRIPTION OF OPERATING SEQUENCE The following is opened during oven operation. When the door is a description of relay (RY-2) which is closed and components...
... read-out displays the time still remaining in , 120 volts A.C. Microwave power operation is set the clock, you must first touch the STOP/CLEAR pad. R-204EWA OPERATION DESCRIPTION OF OPERATING SEQUENCE The following is opened during oven operation. When the door is a description of relay (RY-2) which is closed and components...
Service Manual
Page 9
...µF RECTIFIER Figure O-2. CLOCK APPEARS ON DISPLAY NOTE: " " indicates components with potential above 250V. "START" PAD TOUCHED C/T FUSE MAGNETRON THERMAL CUT-OUT COM. DOOR CLOSED 2. R-204EWA SCHEMATIC NOTE: CONDITION OF OVEN 1. DOOR CLOSED 2.
...µF RECTIFIER Figure O-2. CLOCK APPEARS ON DISPLAY NOTE: " " indicates components with potential above 250V. "START" PAD TOUCHED C/T FUSE MAGNETRON THERMAL CUT-OUT COM. DOOR CLOSED 2. R-204EWA SCHEMATIC NOTE: CONDITION OF OVEN 1. DOOR CLOSED 2.
Service Manual
Page 10
... is opened , the monitor switch contacts close . 3. However, when abnormally high temperatures are in the timer, the C/T fuse will open at the oven cavity. C/T FUSE 1. R-204EWA DESCRIPTION AND FUNCTION OF COMPONENTS DOOR OPEN MECHANISM The door is opened , the switches interrupt the power to all high voltage components. NOTE: C/T FUSE AND...
... is opened , the monitor switch contacts close . 3. However, when abnormally high temperatures are in the timer, the C/T fuse will open at the oven cavity. C/T FUSE 1. R-204EWA DESCRIPTION AND FUNCTION OF COMPONENTS DOOR OPEN MECHANISM The door is opened , the switches interrupt the power to all high voltage components. NOTE: C/T FUSE AND...
Service Manual
Page 11
... performed. IMPORTANT: If the oven becomes inoperative because of the power transformer. 5. Many of the possible causes of Operation in performing the checks. TROUBLESHOOTING GUIDE R-204EWA Never touch any part in the circuit with your hand or an uninsulated tool while the power supply is performed with the power supply cord...
... performed. IMPORTANT: If the oven becomes inoperative because of the power transformer. 5. Many of the possible causes of Operation in performing the checks. TROUBLESHOOTING GUIDE R-204EWA Never touch any part in the circuit with your hand or an uninsulated tool while the power supply is performed with the power supply cord...
Service Manual
Page 12
... food is first plugged into EXPRESS DEFROST/COMPU DEFROST but extremely uneven heating is opened. Disconnect the power supply cord, and then remove outer case. 2. R-204EWA TEST PROCEDURE CK = Check / RE = Replace RE CK A B C D E F F G H RE RE CK I/K CK CK CK J M L POSSIBLE CAUSE AND DEFECTIVE PARTS SHORT IN POWER CORD SHORT OR...
... food is first plugged into EXPRESS DEFROST/COMPU DEFROST but extremely uneven heating is opened. Disconnect the power supply cord, and then remove outer case. 2. R-204EWA TEST PROCEDURE CK = Check / RE = Replace RE CK A B C D E F F G H RE RE CK I/K CK CK CK J M L POSSIBLE CAUSE AND DEFECTIVE PARTS SHORT IN POWER CORD SHORT OR...
Service Manual
Page 13
... ohmmeter leads between the magnetron filament leads and chassis ground. Remove the cup from components during testing. 6. The normal result should indicate an infinite resistance. R-204EWA TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 5. Reconnect the power supply cord after the outer case is clean. Reconnect all functions. (HIGH VOLTAGES ARE PRESENT AT...
... ohmmeter leads between the magnetron filament leads and chassis ground. Remove the cup from components during testing. 6. The normal result should indicate an infinite resistance. R-204EWA TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 5. Reconnect the power supply cord after the outer case is clean. Reconnect all functions. (HIGH VOLTAGES ARE PRESENT AT...
Service Manual
Page 14
...: IF THE THERMAL CUT-OUT INDICATES AN OPEN CIRCUIT AT ROOM TEMPERATURE, REPLACE THERMAL CUT-OUT. Discharge high voltage capacitor. 4. The meter should indicate a closed . R-204EWA TEST PROCEDURES PROCEDURE LETTER C HIGH VOLTAGE RECTIFIER TEST COMPONENT TEST 1. Disconnect the power supply cord, and then remove outer case. 2. Isolate the rectifier from components...
...: IF THE THERMAL CUT-OUT INDICATES AN OPEN CIRCUIT AT ROOM TEMPERATURE, REPLACE THERMAL CUT-OUT. Discharge high voltage capacitor. 4. The meter should indicate a closed . R-204EWA TEST PROCEDURES PROCEDURE LETTER C HIGH VOLTAGE RECTIFIER TEST COMPONENT TEST 1. Disconnect the power supply cord, and then remove outer case. 2. Isolate the rectifier from components...
Service Manual
Page 15
..., make sure that the secondary interlock switch and the primary interlock relay are closed circuit with the door opened (in ), the meter should be defective. R-204EWA TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 6. Isolate the switch and connect the ohmmeter to the common (COM.) and normally open . 3. Reconnect the power supply cord...
..., make sure that the secondary interlock switch and the primary interlock relay are closed circuit with the door opened (in ), the meter should be defective. R-204EWA TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 6. Isolate the switch and connect the ohmmeter to the common (COM.) and normally open . 3. Reconnect the power supply cord...
Service Manual
Page 16
... cooling fan for proper operation and the air guide for proper air flow through the ovens venting system. The following symptoms indicate a defective key unit. R-204EWA TEST PROCEDURES PROCEDURE LETTER H BLOWN C/T FUSE TEST COMPONENT TEST 1. c) When touching the pads, sometimes a pad produces no signal at all functions. Disconnect the power supply...
... cooling fan for proper operation and the air guide for proper air flow through the ovens venting system. The following symptoms indicate a defective key unit. R-204EWA TEST PROCEDURES PROCEDURE LETTER H BLOWN C/T FUSE TEST COMPONENT TEST 1. c) When touching the pads, sometimes a pad produces no signal at all functions. Disconnect the power supply...
Service Manual
Page 17
... when the door is installed. 8) Run the oven and check all functions. 15 Reconnect all digits flicker. 2-3 Other possible problems caused by clearing with pads. R-204EWA TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 2) Open the door and block it is faulty and must be replaced. c) Only one indicator does not light. f) A certain...
... when the door is installed. 8) Run the oven and check all functions. 15 Reconnect all digits flicker. 2-3 Other possible problems caused by clearing with pads. R-204EWA TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 2) Open the door and block it is faulty and must be replaced. c) Only one indicator does not light. f) A certain...
Service Manual
Page 18
... 2 pin connector (A) and the common terminal of the power transformer. 5. Run the oven and check all leads removed from other components and oven chassis by D.C. R-204EWA PROCEDURE LETTER TEST PROCEDURES COMPONENT TEST G 6 G 5 G 4 G 3 G 2 G 1 G 7 BEVERAGE 6 G 8 FRESH VEGETABLES 3 G 9 ROLLS & TIMER MUFFINS CLOCK G10 9 2 DINNER MINUTE PLATE PLUS 5 4 EXPRESS POWER DEFROST LEVEL 0 1 BAKED STOP POTATOES...
... 2 pin connector (A) and the common terminal of the power transformer. 5. Run the oven and check all leads removed from other components and oven chassis by D.C. R-204EWA PROCEDURE LETTER TEST PROCEDURES COMPONENT TEST G 6 G 5 G 4 G 3 G 2 G 1 G 7 BEVERAGE 6 G 8 FRESH VEGETABLES 3 G 9 ROLLS & TIMER MUFFINS CLOCK G10 9 2 DINNER MINUTE PLATE PLUS 5 4 EXPRESS POWER DEFROST LEVEL 0 1 BAKED STOP POTATOES...
Service Manual
Page 19
... defective. STEPS OCCURRENCE CAUSE OR CORRECTION 1 Only pattern at primary side of the relay RY2. CAUSE OR CORRECTION Check supply voltage and oven power cord. R-204EWA TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 1. The rated AC voltage is approximately 563Ω ± 10%). Check for burned damage and examine the transformer with...
... defective. STEPS OCCURRENCE CAUSE OR CORRECTION 1 Only pattern at primary side of the relay RY2. CAUSE OR CORRECTION Check supply voltage and oven power cord. R-204EWA TEST PROCEDURES PROCEDURE LETTER COMPONENT TEST 1. The rated AC voltage is approximately 563Ω ± 10%). Check for burned damage and examine the transformer with...
Service Manual
Page 20
... it works on commercial frequency. 7) Door Sensing Switch A switch to "tell" the LSI if the door is responsive to signals from the AC line voltage. R-204EWA 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...
... it works on commercial frequency. 7) Door Sensing Switch A switch to "tell" the LSI if the door is responsive to signals from the AC line voltage. R-204EWA 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...