MICROWAVE OVEN SERVICE MANUAL
Contents
1. EV OVEN CAVITY PARTS For Model LMVM20758B LMVM2075ST _ 3530A LMVM2075SB LMVM2075SW LATCH BOARD PARTS INTERIOR PARTS 1 EV INTERIOR PARTS II EV INSTALLATION PARTS Ca _ S Z rs snow C 04 gt COOKING C 408 gt TEMPLATE 06 gt TECHNICAL C07 gt CARE LABEL 8 7 LG Electronics Inc2. MAKE SURE THE WIRE LEADS ARE IN THE CORRECT POSITION WHEN REMOVING THE WIRE LEADS FROM THE PARTS BE SURE TO GRASP THE CONNECTOR NOT THE WIRES B CHECKOUT PROCEDURES 1 CHECKOUT PROCEDURES FOR FUSE BLOWING CAUTION REPLACE BLOWN FUSE WITH 20 AMPERE FUSE PROBLEMS CAUSES Fuse blows immediately after the door is closed Improper operation of the primary interlock secondary Fuse blows immediately after interlock switches and or the interlock monitor switch the door is opened Fuse blows when the door is closed and Malfunction of the high voltage transformer the high START ENTER key is touched voltage capacitor including the diode the magnetron the blower motor or the circuit board NOTES If the fuse is blown by an improper switch operation replace all switches and the fuse at the same time After replacing the defective switches with new ones make sure that they are correctly connected Check for microwave energy leakage according to INTERLOCK ADJUSTMENT PROCEDURES on page 7 12 when the primary interlock secondary interlock switches and or the interlock monitor switches are adjusted or replaced 2 CHECKOUT PROCEDURES FOR RELAY PROBLEM A FAN motor turns on without touching START key PROBLEM A Oven lamp turns on without touching START key when the door is closed when the door is closed E Remove the mate connector of I O CON from
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4. FILAMENT TERMINALS MAGNETRON CHASSIS GROUND MAGNETRON THE OVEN IS TO BE SERVICED ONLY BY PROPERLY QUALIFIED SERVICE PERSONNEL INSIALLATIONS BEFORE YOU BEGIN READ THE FOLLOWING INSTRUCTIONS COMPLETELY AND CAREFULLY PRECAUTIONS ON INSTALLATION A Plug the power supply cord into a 120V AC 60Hz single phase power source with a capacity of at least 20 amperes B Avoid placing the unit in a location where there is direct heat or splashing water C Install the unit on the mounting plate firmly D Place the unit as far away as possible from TV radio etc to prevent interference GROUNDING INSTRUCTIONS For personal safety this appliance must be fully grounded at all times In the event of an electrical short circuit grounding reduces the risk of electrical shock The plug must be plugged into an outlet that is properly installed and grounded CAUTION This unit is equipped with a 3 prong plug for your safety If the wall outlet is a grounded 3 hole type the unit will be grounded automatically Plug with Ground Prong Properly Polarized and Grounded Outlet WARNING Improper use of the grounding plug can result in a risk of electric shock Do not under any circumstances cut or remove the third ground prong from the power cord plug 3 1 OPERATING INSTRUC TIONS CONTROL PANEL SENSOR TOUCH REHEAT POPCORN CHICKEN CHOICES EZ ON CLOCK TIMER
5. Normal Approximately 2 0 to 3 0 Kohms Abnormal Infinite or several ABSOLUTE HUMIDITY SENSOR 1 Disconnect sensor connector from micom computer board 2 Measure resistance terminal to terminal ohm meter scale R X 1000 Normal Approximately BK RD 6 0 Kohms RD WH 3 0 Kohms BK WH 3 0 Kohms Abnormal Infinite or approx 0 ohm STIRRER MOTOR 1 Remove lead wires 2 Measure resistance ohm meter scale Rx1000 Normal Approximately 120 to 135 ohms Abnormal Infinite KEY MATRIX COMPONENTS TEST PROCEDURES RESULTS TOUCH KEY BOARD Measure the resistance between terminal pins of connector KEY CONNECTOR NOTE When reconnecting the FPC connector make sure that the holes on the FPC connector are properly engaged with hooks on the plastic fastener MATRIX CIRCUIT FOR TOUCH KEY BOARD CONNECTOR KEY CON 1 yo HH 47 COOK CUSTOM TIME COOK ion VENT LIGHT CHICKEN AUTO CUSTOM HOLD STOP START LEVEL CLEAR ENTER __ ler 1 3 When When not Resistance touched touched value Less than More than 400 ohms 1 mega ohm FPC CONNECTOR Top TF gt 1 I NOTES AMICROWAVE ENERGY TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS SERVICED FOR ANY REASON
6. the oven and close the door tightly B Set cooking time for 10 minutes C Press DIAL to start Make sure the cavity light comes on The unit will begin cooking and the display window will show the time counting down by seconds D After about 5 minutes make sure the primary interlock switch the secondary interlock switch and the interlock monitor switch operate properly by opening and closing the door several times Press the DIAL key each time the door is closed E Continue operating the unit For long beep sound signal is heard when the time is up The unit will shut off automatically F Confirm the water is hot G Finally measure the output power according to POWER OUTPUT MEASUREMENT on page 7 3 6 1 FEATURES AND SPECIFICATIONS FEATURES A The safety systems incorporated in this model are 1 Primary interlock switch 2 Secondary interlock switch 3 Interlock monitor switch 4 Choke system b Oven cavity thermostat Note This thermostat located on the oven cavity will open and stop the unit from operation only if a high temperature is reached such as a fire created by overcooking food B Any one of 10 power output levels ranging OW to 1100W can be selected by the touch control and electronic computer system SERVICE INFORMATION PRECAUTIONS AND REPAIR SERVICE TIPS PRELIMINARY 3 Do not operate the unit until it is completely repaired if any of the following conditions exist The unit must not
7. 62 OR VP 532A OF OR V 5220Q FOR MONITOR SWITCH TYPE NO SZM V16 FA 63 OR VP 533A OF OR V 5230Q FOR SECONDARY SWITCH TEST AND CHECKOUT PRECEDURES AND TROUBLESHOOTING CAUTIONS 1 DISCONNECT THE POWER SUPPLY CORD FROM THE OUTLET WHENEVER REMOVING THE OUTER CASE FROM THE UNIT PROCEED WITH THE TEST ONLY AFTER DISCHARGING THE HIGH VOLTAGE CAPACITOR AND REMOVING THE LEAD WIRES FROM THE PRIMARY WINDING OF THE HIGH VOLTAGE TRANSFORMER 2 ALL OPERATIONAL CHECKS WITH MICROWAVE ENERGY MUST BE DONE WITH A LOAD 1 LITER OF WATER IN CONTAINER IN THE OVEN A TEST PROCEDURES COMPONENTS TEST RESULTS TRANSFORMER FIEANENT se SECONDARY Q WINDING PRIMARY WINDING 1 Remove wire leads 2 Measure resistance ohm meter scale Rx1 e Primary winding High Approx 0 2 to 0 5 ohms Low Approx 0 2 to 0 5 ohms Secondary winding Approx 50 to 120 ohms Filament winding 0 ohm 3 Measure resistance ohm meter scale Rx1000 Primary winding to ground Normal Infinite Filament winding to ground Normal Infinite MAGNETRON Anene Gasket Chassis 1 Remove wire leads Install the magnetron seal in the correct position Check that the seal is in good condition 2 Measure resistance ohm meter scale Rx1 Normal Less than 1 ohm Filament terminal 3 Measure resistance ohm meter scale Rx1000 Normal Infinite Filament to chassis 7 15 COMPONENTS TEST RE
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9. TIME QUICK DEFROST HOLD CUSTOM CUSTOM SET COOK DEFROST DEFROST VENT ON OFF 5 SPEED LIGHT HI LOW OFF AUTO TIME SET mex jer 4 1 CONTROL PANEL INSTRUCTIONS 1 DISPLAY The Display includes a clock and indicators to tell you time of day cooking time setting and cooking functions selected 2 SOFTEN Touch this pad to soften Butter Ice Cream Cream Cheese and Frozen Juice 3 MELT Touch this pad to melt Butter Magarine Chocolate Cheese and Marshmallows 4 COOK Touch this pad to cook Baked Potato Vegetable Casserole Rice and Frozen Entr e The oven s sensor will tell the oven how long to cook depending on the amount of humidity coming from the food 5 REHEAT Touch this pad to reheat Pizza Slice Dinner Plate Soup Sauce and Casserole The oven s sensor will tell the oven how long to cook depending on the amount of humidity coming from the food 6 POPCORN Touch this pad when popping popcorn in your microwave oven The oven s sensor will tell the oven how long to cook depending on the amount of humidity it detects from the popcorn 7 AUTO DEFROST Meat poultry fish and bread Touch this pad to select food type and defrost food by weight 8 TIME DEFROST Touch this pad to defrost most other frozen foods 9 QUICK DEFROST This pad provides quick defrost for 1 0 pound of frozen food 10 CHICKEN CHOICES Touch this pad
10. be operated a The door does not close firmly b The hinge is broken c The door seal is damaged d The door is bent or warped or there is any other visible damage on the unit that may cause microwave energy leakage NOTE Always keep the seal clean e Make sure that there are no defective parts in the interlock mechanism A SINCE NEARLY 4000 VOLTS EXISTS IN SOME CIRCUITS OF THIS UNIT REPAIRS SHOULD BE CARRIED OUT WITH GREAT CARE The filament leads of magnetron carry High Voltage with respect to ground Extreme caution must be exercised Never plug the unit into a power source to determine which component is defective in high voltage section B TO AVOID POSSIBLE EXPOSURE TO f Make sure that there are no detective parts MICROWAVE ENERGY LEAKAGE THE in the microwave generating and transmission BEFORE SERVICING 1 Before the power is applied a Make sure the primary interlock switch the secondary interlock switch and the interlock monitor switch operate properly by opening and closing the door several by opening and closing the door several times b Make sure the perforated screen and the dielectric choke of the door are correctly and firmly mounted 4 The following items should be checked after the unit is repaired a The interlock monitor switch is connected correctly and firmly b The magnetron gasket is properly positioned and mounted c The waveguide and the oven cavity are intact
11. connector 4 Mount All Power code Mounting Plate Out Case Vent Grille Controller Figure 8 C REMOVING THE DOOR INTERLOCK SWITCHES Figures 9 10 1 Disconnect the wire leads from the interlock Switches 2 Remove two screws securing the Latch Board 3 Make necessary replacements and check microwave energy leakage according to ADJUSTMENT PROCEDURES on page 7 12 Latch Board Figure 9 7 7 Latch Board Primary Interlock Switch Interlock Monitor Switch Secondary Interlock Switch Figure 10 WIRE COLOR SYMBOL COLOR WH WHITE BK BLACK BR BROWN RD RED YL YELLOW PK BL BLUE GY GREY GN GREEN Not Provided D REMOVING MAGNETRON When replacing the magnetron be sure to install the Figures 11 Through 12 magnetron gasket in the correct position and be sure 1 Remove the vent grille by loosening two screws that the gasket is in good condition Figure 11 2 Remove the outcase See 7 6 After replacing the magnetron check for microwave 3 Remove four tap tite screws securing the energy leakage with a survey meter Check magnetron to the wave guide microwave energy leakage must be below the limit 4 Remove the magnetron VERY CAREFULLY of 5 mW cm All service adjustments should be made for minimum microwave energy leakage NOTES readings When remo
12. no microwave energy leakage d The door can be properly closed and the safety switches work properly e The unit must stop when the door is opened or 2 After power is applied the time is up a Make sure the interlock switch mechanism is operating properly by opening and closin the adn 9 The unit must not be operated with any of the above components removed or by passed b Check microwave energy leakage must be below the limit of 5 mW cm All service adjustments should be made for minimum microwave energy leakage readings 7 1 MICROWAVE LEAKAGE TEST CAUTIONS Be sure to check microwave leakage prior to servicing the oven if the oven is operative prior to servicing The service personnel should inform the manufacture importer or assembler of any certified oven unit found to have a microwave emission level in excess of 5 mW cn and should repair any unit found to have excessive emission levels at no cost to the owner and should ascertain the cause of the excessive leakage The service personnel should instruct the owner not to use the unit until the oven has been brought into compliance If the oven operates with the door open the service personnel should Tell the user not to operate the oven Contact the manufacturer and CDRH Center for Devices and Radiological Health immediately NOTE Address on CDRH Office of Compliance HFZ 312 Center for Devices and Radiological Healt
13. ob TAP 2 TAP 1 HV TRANS FORMER CN3 11213 p gi ak Rowi M CAPACITOR hc hs THERMISTOR H MDIODE Ly s ABSOLUTE HUMIDITY SENSOR MAGNETRON CHOKE FILTER FOR CANADA MODEL ONLY CONTROL MODULE WIRE COLORS BL WH YL BN BK PK BL WH RD BK 8 32 1 3 PIN CN3 12 PIN CONNECTOR CN1 CONNECTOR FOR SENSOR MATRIX CIRCUIT FOR TOUCH KEY BOARD KEY MATRIX EE 0 CUSTOM i N N A C 2 C LIGHT HuLoworF CHOICES TIME SET SOFTEN MELT AUTO TIME QUICK CUSTOM HOLD POWER N C STOP START LEVEL CLEAR ENTER oj _ tf 5 2 GENERAL INFORMATION FOR SERVICE GENERAL PRECAUTIONS IN USE A Never operate the unit when it is empty Operating the oven with no load may shorten the life of the magnetron Whenever cooking dry foods dried fish bread etc or a small amount of food be sure to put a glass of water into the cooking compartment The glass turntable may become hot after operating be careful when touching it B Aluminum foil should be avoided because it will disrupt cooking and may cause arcing However small pieces may be used to cover some parts of food to slow the cooking Any aluminum foil used should never be closer than 2 5 cm to any side wall of the oven TRIAL OPERATION After installation the following sequences and results should be checked carefully A Put a container filled with water about 1 liter into
14. 1 GENERAL PRECAUTIONS IN USE iii 6 1 TRIAL OPERATION eran tht coe e edic aa 6 1 FEATURES AND SPECIFICATIONS FEATURES 1 ii 6 1 SERVICE INFORMATION 22 E ERE air 7 1 PRECAUTIONS AND REPAIR SERVICE TIPS 7 1 MICROWAVE LEAKAGE TEST cca ana A Ue e re pov 7 2 POWER OUTPUT MEASUREMENT ii 7 3 DISASSEMBLY INSTRUCTIONS u een ape ete A EY e REIR Ene 7 4 INTERLOCK SYSTEM lia ERR da e EUR 7 12 INTERLOCK CONTINUITY TEST tt eR D Aita 7 14 TEST AND CHECKOUT PROCEDURES AND TROUBLESHOOTING seen 7 15 A TEST PROCEDURES ottenere a AI io 7 15 B CHECKOUT PROCE DURE O uuu regedit Sei eee aaa 7 19 C TROUBLESHOOTING sonic dali Re A TERRE EAR iaia 7 22 EXPEODED VIEW nails 8 1 PART REFERENGE LIST ela PEU rd 9 1 SPEC IAC ATONS Rated Power Consumption 1700W maximum Microwave oven Cook top lamps Ventilation fan Microwave ii 1100W IEC60705 Frequency tia 2450 MHz 50 MHz Power Supply i 120 VAC 60 Hz Rated Current 14 5 Amp Microwave oven Cook top lamps Ventilation fan Magnetron Cooling Forced Air Cooling Rectification ruote rede aed Rectification Voltage Double Half Wave Door Sealing Choke System Safety Devices Ma
15. JUSTMENTS AND CONTIN UITY CHECKS WHEN RECONNECTING THE WIRE LEADS TO ANY PART MAKE SURE THE WIRING CONNE CTIONS AND LEAD COLORS ARE CORRECTLY MATCHED ACCORDING TO THE OVERALL CIR CUIT DIAGRAM ESPECIALLY SWITCHES AND HIGH VOLTAGE CIRCUIT A REMOVING POWER AND CONTROL CIRCUIT BOARD Figures 1 2 and 3 1 Remove a screw securing the control panel assembly to the oven cavity 2 Remove the control panel with pushing it upward 3 Remove the connectors CN1 CN3 CN6 CN7 and wire leads 3 Tap Power Relay RY8 from the circuit board Control Panel Circuit Board N CES 3 Tap Power Relay TUS lt RY8 Figure 1 4 Remove 3 screws securing the circuit board Circuit Board Figure 2 5 Remove the FPC connector from the terminal socket following HOW TO REMOVE THE FPC CONNECTOR on the next page 6 Remove the circuit board from the control bracket carefully Control Bracket FPC Connector S1 Circuit Board Figure 3 7 4 HOW TO REMOVE THE F P C CONNECTOR Follow the steps below as illustrated in Figures 4 and 5 to remove the F P C connector 1 Hold the edges of the plastic fastener with thumb and forefinger Figure 4 2 Lift up the lever of the plastic fastener from the terminal socket by lightly pressing the lever end with forefinger Figure 5 8 Remove the F P C connector from the
16. SULTS Remove wire leads CAPACITOR 2 Measure resistance ohm meter scale Rx1000 e Terminal to terminal Normal 8 Momently indicates several ohm and then gradually returns to infinite Terminal to case Normal Infinite O A DIODE 1 Measure continuity Forward Normal Continuity Some inexpensive ohm meters may indicate infinite resistance in both directions RELAY 8 1 Measure continuity ohm meter scale Rx1000 2 Measure continuity Reverse ohm meter scale Rx1000 9 Abnormal Infinite Normal Infinite CN Abnormal Continuity Power ohm meter scale Rx1 Level Open Close 2 Remove the lead wires and operate oven at 1 4 Sec 18 Sec power level 1 through power level 10 2 6 Sec 16 Sec 3 8 Sec 14 Sec 4 10 Sec 12 Sec 5 12 Sec 10 Sec 6 14Sec 8 Sec 7 16 6 Sec 8 18 Sec 4 Sec 9 20 Sec 2 Sec 10 22Sec 0 5 FAN MOTOR 1 Remove wire leads Normal Approximately 2 Measure resistance ohm meter scale Rx1 Terminal A 35 to 50 ohms Terminal 5 to 15 ohms Abnormal Infinite or several COMPONENTS VENTILATION MOTOR TEST 1 Remove lead wires 2 Measure resistance ohm meter scale Rx1 RESULTS Normal Approximately 20 to 40 ohms Abnormal Infinite TURNTABLE MOTOR 1 Remove wire leads 2 Measure resistance ohm meter scale Rx1000
17. Website http us Igservice com LG MICROWAVE OVEN MODEL LMVM2075SB LMVM2075ST LMVM2075SW BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL February 2007 P NO MFL06272503 Printed in Korea CAUTION WARNING TO SERVICE TECHNICIANS PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY 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 to or loosening of hinges and latches 5 evidence of dropping or abuse Before turning on microwave power for any service test or inspection within the microwave generating compartments check the magnetron wave guide or transmission line and cavity for proper alignment integrity and connections Any defective or misadjusted components in the interlock monitor door seal and microwave generation and transmission systems shall be repaired replaced or adjusted by procedures described in this manual before the oven is released to the owner A Microwave leakage check to verify compliance with the Federal performance standard should be performed on each oven prior to release to the owner Proper operation of
18. eing measured Move probe along shaded area Probe scanning speed Less than 2 5 cm sec 1 in sec MEASUREMENT WITH THE OUTER CASE REMOVED 1 When you replace the magnetron measure for microwave energy leakage before the outer case is installed and after all necessary components are replaced or adjusted Special care should be taken in measuring the following parts Around the magnetron The waveguide WARNING AVOID CONTACTING ANY HIGH VOLTAGE PARTS MEASUREMENT WITH A FULLY ASSEMBLED OVEN 1 After all components including the outer panels are fully assembled measure for microwave energy leakage around the door viewing window the exhaust opening and air inlet openings Microwave energy leakage must not exceed the values prescribed below NOTES Leakage with the outer panels removed less than 5 mW cm Leakage for a fully assembled oven Before the latch switch primary is interrupted with the door in a slightly opened position less than 1 mW cm D POWER OUTPUT MEASUREMENT 1 Microwave power output measurement is made with the microwave oven supplied at its rated voltage and operated at its maximum microwave power setting with a load of 1000 5 g of potable water 2 The water is contained in a cylindrical borosilicate glass vessel having a maximum material thickness of 1 8 3 mm and an outside diameter of approximately 7 6 190mm 3 The oven and the empt
19. gnetron Thermostat Open at 145 C 5 C Close at 60 C 5 C Oven Thermostat Open at 110 C 5 C Close at 0 C 5 C Fuse 20A Primary Interlock Switch Secondary Interlock Switch Interlock Monitor Switch Magrietron urere e er ede wen 2M282J Toshiba Cook top Lamp 12 VAC 20 W Halogen Cavity isnt aire etit 125 V 30 W or 40 W Timer i toD te i Digital up to 99 min in each cooking stage ic Tempered Safety Glass Overall Dimensions 2915 16 W x167 16 H x155 s D Oven Cavity Size 231 2 W x10 H x141 2 D Effective Capacity of Oven Cavity 2 0 Cu ft ACCOSSOL OS rnt dete erts Owner s Manual amp Cooking Guide Installation Manual Exhaust Adapter Exhaust Damper Mounting Kit and Filter Rotating Ring Assembly Glass Tray Metal Rack Guide Tray Defrosting Melting Softening Racking SWITCH CHART PRIMARY SECONDARY INTERLOCK SWITCH MODE INTERLOCK INTERLOCK MONITOR SWITCH SWITCH SWITCH COM COM COM CONDITIONS NO NO NC DOOR OPEN OPEN OPEN CLOSE DOOR CLOSED CLOSE CLOSE OPEN NOTE Use the above switch chart with circuit diagram on page 5 1 1 1 CAUTIONS Unlike other appliances the microwave oven is high voltage and high current equipment Though it is free from danger in ordinary use extre
20. h 1390 Piccard Drive Rockville Maryland 20850 The service personnel should check all surface and vent openings for microwave emission testing Check for microwave energy leakage after every servicing The power density of the microwave radiation leakage emitted by the microwave oven should not exceed 1mW cm sq And always start measuring of an unknown field to assure safety for operating personnel from radiation leakage NOTE The standard is 5mW cm sq while in the customer s home 1mW cm sq stated here is manufacturer s own voluntary standard for units in customer s home EQUIPMENT TESTER VOLTS DC AC Ohmmeter Microwave survey meter Holaday HI 1500 HI 1501 8100 8200 600 cc non conductive material beaker glass or plastic inside diameter approx 8 5 cm 3 2 in Glass thermometer 100 C or 212 F 1 deg scale MEASURING MICROWAVE ENERGY LEAKAGE Narda e Pour 275 15cc of 20 5 C 68 9 F water in a beaker which is graduated to 600 cc and place the beaker on the oven Set the energy leakage monitor to 2450 MHz and use it following the manufacturer s recommended test procedure to assure correct result When measuring the leakage always use the 2 inch bcm spacer supplied with the probe Operate the oven at its maximum output Measure the microwave radiation using and electromagnetic radiation monitor by holding the probe perpendicular to the surface b
21. ith a normal relay continuously operates 4 The buzzer does not sound or continues to sound 5 Some segments of one or more digits do not light up or they continue to light up or segments light when they should not 6 Wrong figures appear 7 The figures of all digits 8 The clock does not keep time properly NOTE A MICROWAVE ENERGY LEAKAGE TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS SERVICED FOR ANY REASON 7 21 uonoj oouelsisoH 81 2 pue ees LS 4012euu02 Jaye yono e2uejsiseJ ensee A joejuoo 6une s joejuoo suny 1094109 1004 LS 4012euuoo Jo 99481515 108105 y99uo yo eoe deu 12 1 09 ueuM 10900 JO pue jou ejdsig g IW3180Hd 5 suono uuoo JO 9JUODUI sung EWON 199109 NO 1 jo uid pue ZA uid uee eq anses N ozi 0 lt sung EWJON pieoq eoe deu EC CN ELI Oct 0 a IVLSONYIHL ALIAVO 61 z uo ONIMOTA ISN
22. me care should be taken during repair DO NOT operate on a 2 wire extension cord during repair and use NEVER TOUCH any oven components or wiring during operation BEFORE TOUCHING any parts of the oven always remove the power plug from the outlet Remove your watches whenever working close to or replacing the Magnetron DO NOT touch any parts of the control panel circuit A resulting static electric discharge may damage this P C B NEVER operate the oven with no load NEVER injure the door seal and front plate of the oven cavity NEVER put iron tools on the magnetron NEVER put anything into the latch hole and the interlock switches area 2 1 MICROWAVE RADIATION Personnel should not be exposed to the microwave energy which may radiate from the magnetron or other microwave generating device if it is improperly used or connection All input and output microwave connections waveguide flange and gasket must be secure never operate the device without a microwave energy absorbing load attached Never look into an open waveguide or antenna while the device is energized Proper operation of the microwave oven requires that the magnetron be assembled to the waveguide and cavity Never operate the magnetron unless it is properly installed Be sure that the magnetron gasket is properly installed around the dome of the tube whenever installing the magnetron ANTENNA Gasket COOLING FIN
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24. ndary switch Connect the ohmmeter leads to the common COM and normally open NO terminals of the switch The meter should indicate a open circuit in the door open condition When the door is closed meter should indicate an closed circuit When the secondary switch operation is abnormal make the necessary adjustment or replace the switch only with the same type of switch C MONITOR SWITCH TEST Disconnect the wire lead from the monitor switch Connect the ohmmeter leads to the common COM and normally closed NC terminals of the switch The meter should indicate closed circuit in the door open condition When the door is closed meter should indicate an open circuit When the monitor switch operation is abnormal replace with the same type of switch NOTE After repairing the door or the interlock system it is necessary to do this continuity test before operating the oven RESULTS SWITCHES Check for continuity of the Wire leads removed switch with an Ohm meter Door open Primary Switch EN Monitor Switch Secondary Switch NOTE After checking for the continuity of switches make sure that they are connected correctly WARNING FOR CONTINUED PROTECTION AGAINST EXCESSIVE RADIATION EMISSION REPLACE ONLY WITH IDENTICAL REPLACEMENT PARTS TYPE NO SZM V16 FA 63 OR VP 533A OF OR V 5230Q FOR PRIMARY SWITCH TYPE NO SZM V16 FA
25. o the chassis Also adjust so the door has no play between the inner door surface and oven frame assembly If the door assembly is not mounted properly microwaves may leak from the clearance between the door and the oven Space M E REMOVING THE VENTILATION MOTOR 1 Remove the mounting plate by loosening mounting plate screws 1 or 2 screws securing it to the back plate See Figure 17 2 Remove MOUNT ALL loosening two screw loosening two screw securing the ventilation Motor and back plate See Figure 18 a Mount All Figure 18 a 3 Carefully pull the ventilation motor ASS Y out of the microwave oven See Figure 18 b Figure 18 b J REMOVING THE TURNTABLE MOTOR K REPLACING THE HUMIDITY SENSOR 1 Remove the glass tray and rotating ring 1 Remove the sensor by removing two screws 2 Remove the turntable shaft VERY CAREFULLY securing it to the air duct See Figure 22 with a hand Figure 19 2 Mount the new humidity sensor to the air duct 8 Remove the base plate by removing 8 screws securing it to the oven cavity Figure 20 4 Disconnect the leadwire from the turntable motor terminals Y 5 Remove the 1 screws securing the turntable motor i to the oven cavity ASS Y Figure 21 NOTES Remove the leadwire from the turntable motor VERY CAREFULLY Be sure to grasp the connector not the wires when removing Wire Leads e Turntable Motor Fig
26. rgy interruption or microwave energy blocking device record the measured values for future reference Also enter the information on the service invoice Should the microwave energy leakage not be more than 1 mW cm after determining that all parts are in good condition functioning properly and genuine replacement parts which are listed in this manual have been used At least once a year have the electromagnetic energy leakage monitor checked for calibration by its manufacturer 2 3 lt 4 187 Mw T2 T1 0 55Mc T2 TO t is measured while the microwave generator is operating at full power Magnetron filament heat up time is not included about sec 7 The water is stirred to equalize temperature throughout the vessel prior to measuring the final water temperature 8 Stirring devices and measuring instruments are selected in order to minimize addition or removal of heat P Where P is the microwave power output in watts Mw is the mass of the water in grams Mc is the mass of the container in grams TO is the ambient temperature in C T1 is the initial temperature of the water in C T2 is the final temperature of the water in C tis the heating time in seconds excluding the magnetron filament heat up time WATER LOAD GLASS TRAY DISASSEMBLY INSTRUCTIONS IMPORTANT NOTES UNIT MUST BE DISCONNECTED FROM ELEC TRICAL OUTLET WHEN MAKING REPAIRS RE PLACEMENTS AD
27. rn the light on high low or off OVERALL CIRC UIT DIAGRAM SCHEMATIC DIAGRAM A CELERE LELE AC MAIN PCB quy CN6 10P CN7 14P Tj 9235 8 7 8 9 10 1213141515 11213 pp pp A i 21 UAR qr F 1413 775 FUSE 20A 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 1___CN6 10P CN7 14P MICOM CONTROLLER ASS Y LV TRANSFORMER 3 WH N wn eae et oven Ta um RY2 2 K 3586 CITOP LAMP 3 TEE H RELAY 3 BL GARAND BK 4 CITOP LAMP RD YL LOWRELAY 107 5 6 RD MOT BK THERMOSTAT e 145 C 60 C L V T RIGO s BN VENTFAN I WH ONIOFF RELY BK sort 44 Loup 10 SECONDARY PRIMARY M SWITCH wH SWITCH ER er YL 2T Di 12 BL RD YL RD BN m power 3 e 4 RELAY WH MONITOR RD TAP SWITCH feme rq 3 DI um RD POWER ESS RELAY
28. rvey meter this sequence See Steps 3 and 4 6 Close the oven door slowly and be sure it is tightly closed Watch the three switches to make sure they are zero to the body of the switches in the following sequence Interlock Monitor Switch Primary Interlock Switch Secondary Interlock Switch NOTE The Interlock Monitor Switch is an added safety check on the Primary and Secondary Interlock Switches If the Primary and Secondary Interlock Switches allow the oven to operate with the door open the Monitor Switch will blow the fuse INTERLOCK CONTINUITY TEST A PRIMARY INTERLOCK SWITCH TEST B S ECONDARY INTERLOCK SWITCH TEST When the door is opened slowly an audible click should be heard at the same time or successively at intervals and the latches should activate the switches with an audible click If the latches do not activate the switches when the door is closed the switches should be a adjusted in accordance with the adjustment procedure Disconnect the wire lead from the primary switch Connect the ohmmeter leads to the common COM and normally open NO terminal of the switch The meter should indicate an open circuit in the door open condition When the door is closed the meter should indicate a closed circuit When the primary switch operation is abnormal make the necessary adjustment or replace the switch only with the same type of switch COMPONENTS TEST PROCEDURE Disconnect the wire lead from the seco
29. terminal socket Plastic fastener Connector Terminal socket Figure 4 Plastic fastener Connector Terminal socket Figure 5 7 5 HOW TO INSERT THE F P C CONNECTOR Follow the steps below as illustrated in Figures 6 and 7 to insert the F P C connector 1 Insert the F P C connector into the terminal socket securely with the fingers 2 Hold the plastic fastener with thumb and forefinger of the other hand and push it slowly into the terminal socket Figure 6 NOTE When reconnecting the F P C connector make sure that the holes on the F P C connector are properly engaged with the hooks on the plastic fastener Lock the level of the plastic fastener into the hook of the terminal socket securely by releasing the fingers Figure 7 Plastic fastener Connector Terminal socket Figure 6 Plastic fastener Connector Terminal socket Figure 7 B REMOVING THE OUT CASE Figure 8 1 Remove the vent grille by removing two screws securing it to the out case 2 Remove two screws securing it to the air duct 8 Remove the mounting plate by turning the screws 1 or 2 screws securing it to the out case 4 Remove two screws on the left central edge and two screws on the right central edge of Base plate Remove the Mount All from the out case by removing one screw securing it to the out case b Remove four screws of the rear cavity 6 Remove the outcase with disconnecting power cord
30. the circuit board Does the unit still operate YES GOOD je ie Defective Replace the circuit board Replace Wire Assembly Wire Assembly Remove the mate connector of I O CON from the circuit board Does the unit still operate YES pe Defective Wire Assembly YES GOOD Replace the circuit board Replace Wire Assembly PROBLEM B FAN motor turns on When the door is closed and PROBLEM B Oven lamp turns on When the door is closed and START key is touched YES Measure the voltage at pin NO 1 6 of CN1 Voltage reading 120 V AC p ps ne Replace the Defective circuit board FAN motor Replace FAN motor 7 20 START key is touched YES p Measure the voltage at pin NO 1 4 of CN1 Voltage reading 120 V AC ud ps Replace the Defective circuit board Oven lamp Replace Oven lamp 3 CHECKOUT PROCEDURES FOR CIRCUIT BOARD The following symptoms indicate a defective circuit board 1 Check the input current If the input current is more than 20A check the magnetron and wiring If the input current is less than 0 5 A there is no input to the H V T 2 The start function fails to operate but the high voltage Systems the interlock switches the door sensing and the relay check good 3 The unit w
31. the microwave ovens requires that the magnetron be assembled to the wave guide and cavity Never operate the magnetron unless it is properly installed Be sure that the magnetron gasket is properly installed around the dome of the tube whenever installing the magnetron Routine service safety procedures should be exercised at all times Untrained personnel should not attempt service without a thorough review of the test procedures and safety information contained in this manual 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 TABLE OF CONTENTS Page SAFETY PREGAUTIONS oue ir Inside front page SPECIFICATIONS 5 2 m rh ti en tee o tete neo te Hec ue tede er BEL Dv te oer E eich eet a 1 1 CAUTIONS ssi etat oce n e eR t a A da ala Hie eee pr du p a 2 1 INSTALLATIONS 3 me oe eret pci E o e P dee ne aen P pe dea te db iet ped des 3 1 OPERATING INSTRUGTIONS E e RR E Rte te P PEOR AE di eae e 4 1 teras et e de ce e b e eet ee toa omes ot i ne i tod 4 1 CONTROL PANEL INSTRUCTIONS iii 4 2 OVERALL CIRCUIT DIAGRAM ii 5 1 SCHEMATIC DIAGRAM ea p me e recte e be ce e ira 5 1 MATRIX CIRCUIT FOR TOUCH KEY BOARD i 5 2 GENERAL INFORMATION FOR SERVICE 6
32. to cook chicken wings chicken nugget spicy chicken and Mexican chicken 11 HOLD WARM Touch this pad to keep hot cooked foods warm in your microwave oven for up to 90 minutes 12 EZ ON Touch this pad to set and start quickly at 10096 power level 4 2 13 CUSTOM SET Touch this pad to change the oven s default setting for sound clock disply speed and defrost weight 14 CLOCK Touch this pad to enter the time of day 15 CUSTOM COOK Touch this pad to recall one cooking instruction previously programmed into memory 16 TIMER Touch this pad to set the timer 17 COOK TIME Touch this pad to to set a cooking time 18 POWER LEVEL Touch this pad to select a cooking power level 19 MORE Touch this pad to add ten seconds of cooking time each time you press it 20 LESS Touch this pad to subtract ten seconds of cooking time each time you press it 21 NUMBER Touch number pads to enter cooking time power level quantities or weights 22 START ENTER Touch this pad to start a function If you open the door after oven begins to cook touch START ENTER again 23 STOP CLEAR Touch this pad to stop the oven or to clear all entries 24 VENT ON OFF Touch this pad to turn the fan on off 25 VENT 5 SPEED Touch this pad to choose one of 5 fan speeds 26 VENT AUTO TIME SET Touch this pad when setting ventilation time 1 3 5 10 and 30 minutes 27 LIGHT H LOW OFF Touch this pad to tu
33. ure 21 INTERLOCK SYSTEM INTERLOCK MECHANISM The door lock mechanism is a device which has been specially designed to eliminate completely microwave activity when the door is opened during cooking and thus to prevent the danger resulting from the microwave leakage ADJUSTMENT PROCEDURES To avoid possible exposure to microwave energy leakage adjust the door latches and interlock switches using the following procedure The Interlock Monitor and Primary Interlock Switch act as the final safety switch protecting the user from microwave energy The terminals between COM and NC of the Interlock Monitor must close when the door is opened After adjusting the Interlock Monitor Switch make sure that it is correctly connected Mounting of the primary monitor secondary switches to the latch board T Latch Board Y 1 Primary Interlock Switch Interlock Monitor Switch Secondary Interlock Switch Figure 23 a LATCH 0 1 64 LATCH BOARD Figure 23 b 0 1 64 CHECK THE DOOR LATCH AND SWITCH CLOSING NOTE The outer cover of the microwave oven is removed 1 Set the microwave oven on its side so that you can see the latch board and the switches as shown in Figure 23 a 2 Close the door tightly and check gaps A and B to be sure they are no more than 1 64 0 5 mm See Figure 23 b for close up view of gaps A and B door latches If all gaps are less than 1 64 0 5 mm adj
34. ustment of the latch board may not be necessary Go to Steps 5 and 6 to check the sequence of the switches NOTE To correct sequence of the Primary Interlock Switch Secondary Interlock Switch and the Interlock Monitor Switch is very important If any gap is larger than 1 64 0 5 mm you will need to adjust the latch board Go to step 3 and follow all steps in order ADJUST THE LATCH AND SWITCH CLOSING 8 Loosen the two screws holding the plastic latch board as shown 4 With the oven door closed tightly move the latch board upward toward the top of the oven and or away from the door latch until the gaps are less than 1 64 0 5 mm Hold the latch board tightly in this position until you check the sequence of the switches in steps 5 and 6 TEST THE LATCH AND SWITCH SEQUENCE 7 When you achieve the proper sequence of b Open the oven door slowly Watch the door latch the Secondary Switch Release Rod and Lever switches in Steps 5 and 6 tighten the latch board on the switches to make sure they are zero to the screws at that point body of the switches in the following sequence TEST THE MICROWAVE ENERGY LEAKAGE Primary Interlock Switch Secondary Interlock Switch Make sure the microwave energy leakage is below the Interlock Monitor Switch limit of 1mW crr with a 275 ml water load and 5mW cm with a 275 ml water load without the Adjust the latch board until the switches operate in cabinet when measured with a su
35. ving the magnetron make sure that its dome does not hit any adjacent parts or it may be damaged Mount All Magnetron Figure 12 7 8 E REMOVING STIRRER FAN F REMOVING DOOR Figure 15 Figures 13 and 14 1 Remove the vent grille by two screws securing it 1 Remove one rivet ASS Y securing it to the oven to the outcase loosening upper plate by using knife blade 2 Lift up and draw the door 2 Pull out the stirrer fan cover 3 Remove two rivets ASS Y securiting it to the oven upper plate by using knife blade 4 Remove the stirrer fan NOTES After replacing the door be sure to check that the primary interlock switch the secondary interlock switch and the interlock monitor switch is in good operating normally After replacing the door check for microwave energy leakage with a survey meter Microwave energy leakage must be below the limit of 5mW cm With a 275 ml water load Figure 13 Figure 15 G DISASSEMBLING DOOR Figure 16 1 Remove the dielectric choke by using knife blade or small screw driver etc 2 Remove two screws securing it to the door handle CAUTION Be careful not to damage door seal plate with the screwdriver Figure 14 Door Screen Figure 16 7 9 H ASSEMBLING DOOR 1 When mounting the door assembly to the oven assembly be sure to adjust the door assembly parallel t
36. y vessel are at ambient Temperature TO prior to the start of the test 4 The initial temperature T1 of the water is 10 1 50 F It is measured immediately before the water is added to the vessel After addition of the water to the vessel the load is immediately placed on the center of the turntable which is in the lowest position and the microwave power switched on The time t for the temperature of the water to rise by a value T of 10 1 K is measured where t is the time in seconds and T is the temperature rise The initial and final water temperatures are selected so that the maximum difference between the final water temperature and the ambient temperature is 5 K The microwave power output P in watts is calculated from the following formula al NOTE WHEN MEASURING 1 Do not exceed meter full scale deflection 2 The test probe must be removed no faster than 1 inch sec 2 5cm sec along the shaded area otherwise a false reading may result The test probe must be held with the grip portion of the handle A false reading may result if the operator s hand is between the handle and the probe When testing near a corner of the door keep the probe perpendicular to the surface making sure the probe horizontally along the oven surface this may possibly cause probe damage 3 lt 4 RECORD KEEPING AND NOTIFICATION AFTER MEASUREMENT 1 After adjustment and repair of any microwave ene
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