Basic Information This Manual has been prepared to provide Electrolux Service Personnel with Operation and Service Information for ELECTROLUX MICROWAVE OVENS, EI30BM55HB, EI30BM55HS, EI30BM55HW and EI30BM55HZ. Table of Contents Section 1 Basic Information ........Positive Lock ® Connector (No-Case Type)..
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THIS SERVICE MANUAL IS INTENDED FOR USE BY PERSONS HAVING ELECTRICAL AND MECHNICAL TRAINING AND A LEVEL OF KNOWLEDGE OF THESE SUBJECTS GENERALLY CONSIDERED ACCEPTABLE IN THE APPLIANCE REPAIR TRADE. ELECTROLUX HOME PRODUCTS CANNOT BE RESPONSIBLE, NOR ASSUME ANY LIABILITY, FOR INJURY OR DAMAGE OF ANY KIND ARISING FROM THE USE OF THIS MANUAL.
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 Electrolux HOME PRODUCTS, INC. immediately. If the unit operates with the door open, service person should 1 ) tell the user not to operate the oven and 2) contact Electrolux HOME PRODUCTS, INC.
Basic Information WARNING 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) INVERTER UNIT THAT INCLUDES HIGH VOLTAGE CAPACITOR, HIGH VOLTAGE POWER TRANSFORMER, HIGH VOLTAGE RECTIFIER, HEAT SINK ETC., AND MAGNETRON, HIGH VOLTAGE HARNESS ETC..
Basic Information 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 1 mW/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.
Basic Information 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 accordance 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.
Basic Information Oven Diagram FRONT VIEW 1. Microwave oven door with see-through window 2. Door hinges 3. Waveguide cover: DO NOT REMOVE. 4. Turntable motor shaft 5. Microwave oven light It will light when microwave oven is operating or door is open. 6.
Operation Operating Sequence 6. When the door is opened during a cook cycle, monitor switch, door sensing switch, secondary Description interlock switch, and primary interlock relay are activated with the following results. The circuits The following is a description of component functions to the stirrer motor, the cooling fan motor, the during oven operation.
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Operation VARIABLE COOKING An example of how the sensor works: When Variable Cooking Power is programmed, the (BAKED POTATOES) 120 volts A.C. is supplied to the power transformer intermittently through the contacts of relay (RY2) which is operated by the control unit within an interval second time base.
Operation 4. When the sensor detects the vapor emitted from the food, the display 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.
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Operation EI30BM55HW SCHEMATIC NOTE: CONDITION OF OVEN NOTE: " " indicates components with potentials above 250V 1. DOOR CLOSED 2. CLOCK APPEARS ON DISPLAY 120VAC 60Hz MAGNETRON TEMP.FUSE OVEN THERMAL 150ºC CUT OUT 145ºC POWER UNIT CN-M HOOD FAN THERMOSTAT 60ºC PRIMARY INTERLOCK...
Operation Component Descriptions their being normally open contact switches. And the contacts of relay (RY1) are in the ON condition (contacts close). DOOR OPEN MECHANISM 2. As the door goes to a closed position, the The door is opened by pulling the door handle, refer monitor switch contacts are first opened and to the Figure D-1.
Operation HOOD FAN MOTOR Touch Control Panel Operation The hood fan motor is a three-speed, single-phase, double pole induction type, requiring a hood fan The touch control section consists of the following capacitor. It is located outside the upper rear part of units as shown in the touch control panel circuit.
Operation 6) Power Source Circuit Humidity Sensor Circuit This circuit generates voltages necessary in the control unit from the AC line voltage. In addition, (1) Structure of Humidity Sensor the synchronizing signal is available in order to The humidity sensor includes two thermistors as compose a basic standard time in the clock shown in the illustration.
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Operation (3) Detector Circuit of Humidity Sensor Circuit This detector circuit is used to detect the output voltage of the humidity circuit to allow the LSI to control sensor cooking of the unit. When the unit is set in the sensor cooking mode, 16 seconds clearing cycle occurs than the detector circuit starts to function and the LSI observes the initial voltage available at its AN1 terminal.
Troubleshooting Troubleshooting Guide 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. IMPORTANT: If the oven becomes inoperative because of a blown monitor fuse, check the monitor switch, relay (RY1) primary interlock relay (RY2), door sensing switch and secondary interlock switch before replacing the monitor fuse.
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Troubleshooting CK = Check / RE = Replace HUMIDITY SENSOR NOISE FILTER CK LOW VOLTAGE CK NO POWE R AT OUTLET RE SHORTED IN POWER CORD CK OPENED OR SHOR TED WIRING CK HOOD MOTOR CAPACITO R RE COOK TOP LAMP OR SOCKET CK TURNT ABLE OFF CONDITION RE ST IRRER M OTOR RE TURNT ABLE MOTOR...
Troubleshooting Test Procedures Procedure Component Test Letter MAGNETRON ASSEMBLY TEST 1. Disconnect the power supply cord, and then remove outer case. 2. Open the door and block it open. 3. To discharge high voltage capacitor, wait for 60 seconds. 4. 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.
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Troubleshooting Procedure Component Test Letter POWER TRANSFORMER TEST WARNING: DO NOT TOUCH THE COMPONENTS OF THE POWER TRANSFORMER WHILE POWER TRANSFORMER IS ENERGIZED. IT IS DANGEROUS BECAUSE THIS HAS HIGH VOLTAGE COMPONENTS. (HIGH VOLTAGES ARE PRESENT AT THE HIGH VOLTAGE TERMINAL, SO DO NOT ATTEMPT TO MEASURE THE FILAMENT AND HIGH VOLTAGE.) 1.
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Troubleshooting Procedure Component Test Letter HIGH VOLTAGE CAPACITOR TEST 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. If the capacitor is open, no high voltage will be available to the magnetron. Disconnect input leads and check for short or open between the terminals using an ohmmeter.
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Troubleshooting Procedure Component Test Letter SECONDARY INTERLOCK SWITCH TEST 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. Isolate the switch and connect the ohmmeter to the common (COM.) and normally open (NO) terminal of the switch.
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Troubleshooting Procedure Component Test Letter MONITOR SWITCH TEST 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. Before performing this test, make sure that the secondary interlock switch and the primary interlock relay are operating properly, according to the above Switch Test Procedure.
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Troubleshooting Procedure Component Test Letter HOOD THERMOSTAT TEST 1. THERMOSTAT (60°C ON) 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. A continuity check across the thermal cut-out terminals should indicate an open circuit unless the temperature of the thermal cut-out reaches approximately 140°F(60°C) or more.
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Troubleshooting Procedure Component Test Letter TOUCH CONTROL PANEL ASSEMBLY TEST The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore, unlike conventional microwave ovens, proper maintenance cannot be performed with only a voltmeter and ohmmeter. In this service manual, the touch control panel assembly is divided into three units, Control Unit, Keyboard Unit and Power Unit, and troubleshooting by unit replacement is described according to the symptoms indicated.
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Troubleshooting Procedure Component Test Letter 2) Other possible problems caused by defective control unit. a) Buzzer does not sound or continues to sound. b) Clock does not operate properly. c) Cooking is not possible. 3) Power Unit or Touch Control Transformer a) Fan motor, stirrer motor, oven lamp or electrical parts do not turn on or do not turn off.
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Troubleshooting Procedure Component Test Letter RELAY TEST 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.
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Troubleshooting Procedure Component Test Letter PROCEDURES TO BE TAKEN WHEN THE FUSE ON THE PRINTED WIRING BOARD (PWB) IS OPEN. To protect the electronic circuits, this model is provided with a fuse added to the primary on the PWB. 1. Fuse check and repairs. 1) Disconnect the power supply cord.
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Troubleshooting Procedure Component Test Letter HUMIDITY SENSOR TEST Checking the initial sensor cooking condition WARNING: The oven should be fully assembled before following procedure. 1) The oven should be plugged in at least two minutes before sensor cooking. 2) Room temperature should not exceed 35°C. 3) The unit should not be installed in any area where heat and steam are generated.
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Troubleshooting Procedure Component Test Letter Reconnect the oven to the power supply and check the sensor cook operation as follows: a) Fill approximately 200 milliliters of tap water in a 1000 milliliter measuring cup. b) Place the container on the center of tray in the oven cavity. c) Close the door.
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Troubleshooting Procedure Component Test Letter NOISE FILTER TEST 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.
Component Teardown Servicing After checking the performance of the touch control panel, 1) Disconnect the power supply cord. 1. Precautions for Handling Electronic 2) Open the door and block it open. Components 3) Re-connect the leads to the primary of the This unit uses CMOS LSI in the integral part of inverter unit.
Component Teardown 3. Servicing Tools 3. Soldering Tools required to service the touch control panel As the melting point of lead-free solder (Sn-Ag- assembly. Cu) is higher and has poorer wettability, (flow), to 1) Soldering iron: 60W prevent damage to the land of the PWB, extreme (It is recommended to use a soldering iron with a care should be taken not to leave the bit in con- grounding terminal.)
Component Teardown WARNING 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) MAGNETRON, POWER TRANSFORMER, HIGH VOLTAGE HARNESS ETC.. WARNING AVOID POSSIBLE EXPOSURE TO MICROWAVE ENERGY. PLEASE FOLLOW THE INSTRUCTIONS BELOW BEFORE OPERATING THE OVEN.
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Component Teardown WARNING TO PREVENT AN ELECTRIC SHOCK, TAKE THE FOLLOWING PRECAUTIONS. 1. BEFORE WIRING, 1) DISCONNECT THE POWER SUPPLY CORD. 2) OPEN THE DOOR BLOCK IT OPEN. 3) TO DISCHARGE THE HIGH VOLTAGE CAPACITOR, WAIT FOR 60 SECONDS. 2. DON’T LET THE WIRE LEADS TOUCH TO THE FOLLOWING PARTS; 1) HIGH VOLTAGE PARTS: MAGNETRON, HIGH VOLTAGE TRANSFORMER, HIGH VOLTAGE, CAPACITOR AND HIGH VOLTAGE RECTIFIER ASSEMBLY.
Component Teardown Removal of Oven From Wall Outer Case Removal (Two persons recommended to remove the oven) Remove the oven from the wall, and proceed as 1. Disconnect the power supply cord, and uncoil the follows: power supply cord. 1. Disconnect the power supply cord. 2.
Component Teardown Magnetron Removal High Voltage Rectifier and High Voltage Capacitor Removal 1. Disconnect the power supply cord and remove the oven from wall and remove outer case. (Refer 1. Disconnect the power supply cord and remove to procedure of "Removal of Oven from Wall" and the oven from wall and remove outer case.
Component Teardown Hood Fan Motor, Hood Duct, Oven 19.Remove the hood duct from the oven cavity by lift- ing it up. Lamp Socket and Humidity Sensor 20. Release the snap band of control harness A from Replacement the hood duct. 21.
Component Teardown Power Transformer Removal Hood Fan Thermostat (60ºC ON and 70ºC Off) Removal 1. Removal 1. Disconnect the power supply cord, remove the 1. Disconnect the power supply cord, remove the oven from wall, and remove outer case. (Refer to oven from wall and remove outer case (Refer to procedure of “REMOVAL of OVEN FROM WALL”...
Component Teardown Cooling Fan Motor Removal 2. INSTALLATION 1. Install the fan motor to the fan duct with the two 1. REMOVAL (2) screws. 2. Install the fan blade to the fan motor shaft accord- 1. Disconnect the power supply cord, remove the ing to the following procedure.
Component Teardown Positive Lock ® Connector (No- Cook Top Lamp Socket Case Type) Removal 1. Disconnect the power supply cord. 2. Remove the three (3) screws holding the 1. Disconnect the power supply cord and remove deflector to the base cover. the oven from wall and remove outer case.
Component Teardown Stirrer Cover and Stirrer Antenna Door Sensing Switch, Secondary Interlock Switch and Monitor Installation Switch Removal 1. Put the stirrer antenna fan on the wave guide to match the stirrer antenna shaft to the center of 1. REMOVAL the stirrer hole.
Component Teardown Door Sensing Switch, Secondary 2. After adjustment, check the following. 1. In and out play of door remains less than 0.5mm Interlock Switch and Monitor when in the latched position. First check upper Switch Adjustment position of latch hook, pushing and pulling upper portion of door toward the oven face.
Component Teardown Door Replacement After any servicing, make sure of the following : 1. Door latch heads smoothly catch latch hook 1. Disconnect the power supply cord and remove through latch holes and that latch head goes the oven from wall and remove outer case. (Refer to procedure of “Removal of Oven from Wall”...
Component Teardown Door Disassembly Door stopper 1. Disconnect the power supply cord and remove the oven from wall and remove outer case. (Refer Choke cover to procedure of “Removal of Oven from Wall” and “Outer case Removal”) 2. Open the door and block it open. 3.
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