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website http://www.lgservice.com
MICROWAVE OVEN
SERVICE MANUAL
MODEL : LRMM1430SW
LRMM1430SB
CAUTION
BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
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CAUTION WARNING TO SERVICE TECHNICIANS 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. b. Make the following safety checks on all ovens to be serviced before activating the magnetron or other microwave source, and make repairs as necessary; (1) Interlock operation, (2) proper door closing, (3) seal and sealing surfaces (arcing, wear, and other damage), (4) damage
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FOREWORD Read this Manual carefully. Failure to adhere to or observe the information in this Manual may result in exposing yourself to the Microwave Energy normally contained within the oven cavity. MODEL LRMM1430SW LRMM1430SB MECHANICAL SERVICE INFORMATION TABLE OF CONTENTS 1. Adjustment Procedures ....................................................................................................................................... 3-4 2. Precautions on Installation ...........................
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ADJUST THE LATCH AND SWITCH CLOSINGS 1. ADJUSTMENT PROCEDURES To avoid possible exposure to microwave energy (3) Loosen the screw holding the plastic latch board as leakage, adjust the door latches and interlock switches, shown. using the following procedure. (4) With the oven door closed tightly, move the latch board upward toward the top of the oven and/or away from the ONLY AUTHORIZED SERVICE PERSONNEL door latch until the gaps are less than 1/64” (0.5 mm). SHOULD MAKE THIS ADJUSTMENT. Hold
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LATCH BOARD SECONDARY INTERLOCK DOOR LATCH SWITCH MONITOR INTERLOCK SWITCH PRIMARY INTERLOCK SWITCH Figure 1-a LATCH (B) 0-1/64" LATCH BOARD Figure 1-b (A) 0-1/64" -4-
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2. PRECAUTIONS ON INSTALLATION 4. TRIAL OPERATION (Figure 2) After installation, the following sequences and results A. Plug the power supply cord into a 120 V AC, 60 Hz, should be checked carefully. single-phase power source with a capacity of at least 20 A. Put a container filled with water (about 1 liter) into the amperes. oven, and close the door tightly. B. Since the unit weights about 38 lbs., be sure to place it B. Touch the STOP/CLEAR and the COOK TIME keys. “0” on a sturdy and fla
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SPECIFICATIONS Rated Power Consumption 1250W maximum Output 1200W maximum (*IEC 60705 Rating standard) Adjustable 0W through 1200W, 10 steps Frequency 2,450 MHz 50 MHz Power Supply 120V 12V AC, 60Hz Rated Current 11 Amp. Magnetron Cooling Forced Air Cooling Microwave Stirring Turntable Rectification Rectification Voltage Doubler Half-Wave (Inverter type) Door Sealing Choke System Safety Devices Thermostat: Open at 90 ˚C 5 ˚C Close at 75 ˚C 5 ˚C Fuse(20A) Primary Interlock Switch Secondary I
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6. OVERALL CIRCUIT DIAGRAM A. SCHEMATIC DIAGRAM Figure 3 -7-
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B. MATRIX CIRCUIT FOR TOUCH KEY BOARD Figure 4 -8-
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7. OPERATING PROCEDURES A. CONTROL PANEL 2 3 4 5 9 1 12 14 16 17 6 7 8 10 11 13 15 18 19 Figure 5. 1. Display. The Display includes a clock and indicators 10. Q-Defrost. Touch this pad to defrost foods quickly. that tell you time of day, cooking time settings, and 11. More / Less. Touch these pads to adjust cooking cooking functions selected. time in 10 second increments. 2. Sensor Touch. This pad allows you to cook most of 12. Cook time. Touch this pad to set a cooking time. your favorite foo
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B. PANEL INSTRUCTIONS (Figure 5) (9) STOP/CLEAR Key Used to stop the oven or clear all entries except The entire operation is done by simple touch control pads. CLOCK. (1) Display Window (10) AUTO DEFROST key (DEFROST MEAT, POULTRY, Numbers and letters explained in Figure 5 are shown in FISH & BREAD) the display window (Vacuum Fluorescent Tube). Used in setting AUTO DEFROST. (a) The Time in four digits (12-hour indication): 00 Hour 00 Minute. (11) Q DEFROST key (b) Cooking Time of Day in fou
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C. EASY USE CHART (1) CLOCK (6) MELT 1. Touch STOP/CLEAR. 1. Touch STOP/CLEAR. 2. Touch CLOCK. 2. Touch MELT. 3. Touch numbers for correct time of day. Four different melt menus are provided. 4. Touch CLOCK. 3. Select Menu 1 to 4- See cooking guide. 4. Enter the amount of the Category. (2) “HI-POWER” COOKING 1. Touch STOP/CLEAR. (7) AUTO DEFROST 2. Touch COOK TIME. 1. Touch STOP/CLEAR. 3. Touch numbers for desired cooking time. 2. Touch AUTO DEFROST. 4. Touch START. Three diffe
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8. PROCEDURE FOR MEASURING MICROWAVE ENERGY LEAKAGE A. CAUTIONS B. MEASURING MICROWAVE ENERGY LEAKAGE (1) Be sure to check a microwave emission prior to (1) Pour 275 15cc of 20 5 ˚C water in a beaker which is servicing the oven if the oven is operative prior to graduated to 600 cc, and place the beaker in the center servicing. of the oven. (2) The service personnel should inform the manufacturer, (2) Set the energy leakage monitor to 2,450 MHz and use it importer, or assembler of any certi
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D. MEASUREMENT WITH A FULLY ASSEMBLED OVEN G. POWER OUTPUT MEASUREMENT Be sure oven cavity is clean and cool . (not used recently) (1) After all components, including the outer panels, are fully assembled, measure for microwave energy (1) Fill the test beaker with 59 ˚F(15 ˚C) ~ 75 ˚F(24 ˚C) 1 liter tap leakage around the door viewing window, the exhaust water. opening and air inlet openings. (2) Stir the water in the beaker with thermometer (˚F or ˚C) and (2) Microwave energy leakage must no
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9. DISASSEMBLY INSTRUCTIONS Remove deco front IMPORTANT NOTES: UNIT MUST BE DISCONNECTED FROM ELECTRICAL OUTLET WHEN MAKING REPAIRS, RE-PLACEMENTS, ADJUSTMENTS AND CONTINUITY CHECKS. WAIT AT LEAST ONE MINUTE, UNTIL THE HIGH VOLTAGE CAPACITOR IN THE HIGH VOLTAGE POWER SUPPLY HAS FULLY DISCHARGED. THE CAPACITOR SHOULD BE DISCHARGED BY USING INSULATED WIRE - I.E. TEST PROBE CONNECTED TO 10K-OHM RESISTOR IN SERIES TO GROUND. WHEN RECONNECTING THE WIRE LEADS TO Disconnect the lead wires ANY PART,
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C. REMOVING CONTROL CIRCUIT BOARD (Figure 10) D. SEPARATE CAVITY AND BASE PLATE (Figure 11) (1) Remove out case. (1) Remove out case. (2) Remove door assembly. (2) Remove Door Assembly. (3) Unfasten two screws. (3) Remove five screws at the base plate. (4) Lift up and pull out control panel assembly carefully (Front 3 EA, Back 2 EA). from the cavity. (4) Disconnect the lead wires from filter. (5) Remove door frame. (5) Disconnect all the lead wires from main board. (6) Remove the F
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E. AIR GUIDE REMOVAL (Figure 12) G. SENSOR DUCT REMOVAL (Figure 13) (1) Separate cavity and base plate. (1) Remove out case. (2) Unfasten the screws which hold the air guide in the (2) Unfasten the sensor duct screw. base plate. (3) Disconnect sensor lead wire. (3) Unfasten the air guide from hook. (4) Pull the sensor duct out. F. POWER BOARD AND INVERTER MODULE AND Figure 13 SUCTION GUIDE (Figure 12) (1) Separate cavity and base plate. (2) Remove air guide. (3) Unfasten the screws.
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H. MAGNETRON REMOVAL I. REMOVING THE TURNTABLE MOTOR (1) Disconnect the leadwire from the magnetron. (1) Remove the turntable and turntable roller rest. (2) Carefully remove the mounting screws holding the (2) Lay the unit down on its back. magnetron at the waveguide. (3) Remove the turntable motor cover. (3) Remove the magnetron from the waveguide. The turntable base cover is easily removed by pinching the four parts with a wire cutting. NOTE: (4) Disconnect the leadwire from the turntable moto
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J. FAN MOTOR ASSEMBLY REMOVAL K. INTERLOCK SYSTEM (1) Separate cavity and base plate. (1) INTERLOCK MECHANISM (2) Remove air and suction guide.. The door lock mechanism is a device which has been (3) Remove the two screws holding the fan motor ASSEMBLY specially designed to eliminate completely microwave to the suction guide ASSEMBLY. activity when the door is opened during cooking and thus (4) Disconnect the wires and unfasten the screws. to prevent the danger resulting from the microwave (5) P
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10. INTERLOCK CONTINUITY TEST WARNING : FOR CONTINUED PROTECTION AGAINST EXCESSIVE RADIATION EMISSION, REPLACE ONLY WITH IDENTICAL REPLACEMENT PARTS. TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF OR V-5230Q FOR PRIMARY SWITCH TYPE NO. SZM-V 16-FA-62 OR VP-532A-OF OR V-5220Q FOR MONITOR SWITCH TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF OR V-5230Q FOR SECONDARY SWITCH A. PRIMARY INTERLOCK SWITCH TEST B. SECONDARY INTERLOCK SWITCH TEST When the door release button is depressed slowly with Disconnect the wir
