LG LCRT2010ST Service Manual Download

Page: 1 / 35

MICROWAVE OVEN

SERVICE MANUAL

MODEL: LCRT2010ST

CAUTION

BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

Website http://biz.lgservice.com

P/NO : MFL06272518

November, 2010

Printed in Korea

삼

흥

정

판

Internal Use Only

Summary of Contents for LCRT2010ST

Page 1: ...N SERVICE MANUAL MODEL LCRT2010ST CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL Website http biz lgservice com P NO MFL06272518 November 2010 Printed in Korea 삼 흥 정 판 Internal Use Only ...

Page 2: ...r and other damage 4 damage to or loosening of hinges and latches 5 evidence of dropping or abuse C 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 D Any defective or misadjusted components in the interlock monitor door seal...

Page 3: ...4 1 OPERATING SEQUENCE 4 2 SCHEMATIC DIAGRAM 4 3 CIRCUIT DESCRIPTION 4 4 SERVICE INFORMATION 5 1 TOOLS AND MEASURING INSTRUMENTS 5 1 MICROWAVE LEAKAGE TEST 5 1 MEASUREMENT OF MICROWAVE POWER OUTPUT 5 3 DISASSEMBLY AND ADJUSTMENT 5 3 INTERLOCK CONTINUITY TEST 5 7 COMPONENT TEST PROCEDURE 5 8 TROUBLE SHOOTING 5 11 EXPLODED VIEW 6 1 REPLACEMENT PARTS LIST 7 1 ...

Page 4: ...trol System Clock 1 00 12 59 Microwave Power for Variable Cooking Power level HIGH Full power throughout the cooking time 9 Saute approx 90 of Full power 8 Reheat approx 80 7 Med High approx 70 6 Medium approx 60 5 Med Low approx 50 4 Defrost approx 40 3 Low approx 30 2 Simmer approx 20 1 Warm approx 10 Owner s manual cooking guide Glass turntable Roller rest ITEM Model Power Requirement Power Out...

Page 5: ...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 2 1 CAUTIONS Unlike other appliances the microwave oven is high voltage and high current equipment Though it is free from...

Page 6: ...ional surface unit or above a conventional wall oven 5 Use microwave oven in an ambient temperature less than 104 F 40 C 6 Place the microwave oven on a sturdy and flat surface at least 10 cm 4 inches from the wall 7 Place the microwave oven as far away as possible from TV RADIO COMPUTER etc to prevent interference GROUNDING INSTRUCTIONS For personal safety this appliance must be fully grounded at...

Page 7: ...quickly 8 AUTO DEFROST Thispadis anaccurate defrosting method for meat poultryandfishupto6 0lbsor 4 0 kgs 9 SOFTEN Touch this pad to soften butter ice cream cream cheese or frozen juice 10 MELT TTouch this pads to melt butter margarine chocolate cheese or mashmallows 11 NUMBER PADS Touch number pads to enter cooking time power level quantities or weights 12 TIME COOK Touch this pad to set a cookin...

Page 8: ...d pad LOCKED appears on the display TO CANCEL CHILD LOCK Touch and hold pad LOCKED disappears 9 MORE LESS The cook time is adjustable by MORE pad or LESS pad 10 QUICK DEFROST 11 KITCHEN TIMER 12 MELT NOTE Then the oven will start automatically 13 SOFTEN NOTE Then the oven will start automatically 14 CUSTOM SET 15 EXPRESS DEFROST 16 AUTO COOK 4 2 Ez On STOP CLEAR POPCORN STOP CLEAR NUMBER START ENT...

Page 9: ...SCHEMATIC DIAGRAM 4 3 ...

Page 10: ...oximately 2100 volts AC is generated in the secondary of the high voltage transformer which is increased by the action of the high voltage diode and charging of the high voltage capacitor The negative 4 000 Volts DC is applied to the filament of the magnetron WHEN THE OVEN IS SET AT ANY LEVEL EXCEPT MAXIMUM The micom controller controls the ON OFF time of relay 2 by the applied signal to vary the ...

Page 11: ...ity of the microwave radiation leakage emitted by the microwave oven should not exceed 4 mW cm2 Always start measuring of an unknown field to assure safety for operating personnel from radiation leakage NECESSARY MEASURING INSTRUMENTS TESTER VOLTS DC AC Ohmmeter Microwave survey meter Holaday HI 1500 HI 1501 Narda 8100 8200 Inch scale 600 cc non conductive material beaker glass or plastic inside d...

Page 12: ... 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 befween 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 Hold vertically when testing the top and bottom and horizontally along RECORD KEE...

Page 13: ... material thickness of 3 mm and an outside diameter of approximately 190mm The oven and the empty vessel are at ambient temperature prior to the start of the test The initial temperature T1 of the water is 10 2 C 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 thd ...

Page 14: ...d push the door NOTE 1 After replacing the door be sure to check that the primary switch monitor switch and secondary switch operate normally 2 After replacing the door check for microwave energy leakage with a survey meter Microwave energy must be below the limit of 4 mW cm2 with a 275 ml water load 3 When mounting the door assembly to the oven assembly be sure to adjust the door assembly paralle...

Page 15: ...ure to install the magnetron gasket in the correct position and be sure that the gasket is in good condition 3 After replacing the magnetron check for microwave leakage with a survey meter around the magnetron Microwave energy must be below the limit of 5 mW cm2 With a 275 ml water load Make sure that gasket is rigidly attached to the magnetron To prevent microwave leakage tighten the mounting scr...

Page 16: ... Discharge the high voltage capacitor 2 Disconnect the leadwire from magnetron high voltage transformer and capacitor 3 Remove the screw holding the high voltage transformer to the baseplate J FAN MOTOR ASSEMBLY REMOVAL 1 Discharge the high voltage capacitor 2 Disconnect the leadwire from fan motor and high voltage capacitor 3 Remove the two screws holding the the suction guide ASS Y to the oven c...

Page 17: ...to the oven assembly Adjust the latch board in the arrow direction so that oven door will not have any play in it when the door is closed Tighten the mounting screw Check for play in the door by pushing the door release button Door movement should be less than 0 5 mm 1 64 inch Don t push the door release button while making this adjustment Make sure that the latch moves smoothly after adjustment a...

Page 18: ...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 ...

Page 19: ... THE OVEN HIGH VOLTAGE TRANSFORMER Wire leads removed MAGNETRON Wire leads removed Approx 0 2 0 4 ohm Approx 70 100 ohm Less than 1 ohm Normal Infinite Normal Infinite Normal Less than 1 ohm Normal Infinite PRIMARY TERMINAL FILAMENT WINDING COMPONENTS TEST PROCEDURE RESULTS 1 Measure the resistance Ohm meter scale Rx1 and Rx100 Primary winding Secondary winding Filament winding 2 Measure the resis...

Page 20: ...Normal Momentarily indicates several ohms and then gradually returns to infinite Normal Infinite Normal Infinite Abnormal Continuity Normal Continuity Abnormal Infinite Measure the resistance Ohm meter scale Rx1000 Terminal to case Measure the continuity Forward Ohm meter scale Rx10000 Measure the continuity Reverse Ohm meter scale Rx10000 HIGH VOLTAGE DIODE NOTE Some inexpensive meters may indica...

Page 21: ...E WIRE LEADS ARE IN THE CORRECT POSITION WHEN REMOVING THE WIRE LEADS FROM THE PARTS BE SURE TO GRASP THE CONNECTOR NOT THE WIRES Measure the resistance Ohm meter scale R x 1 Normal A Approx 85 100 ohm B Approx 10 25 ohm Abnormal Infinite or several ohm Normal Approx 100 150 ohm Abnormal Infinite or several ohm POWER LEVEL 1 2 3 4 5 6 7 8 9 10 4 sec 6 sec 8 sec 10 sec 12 sec 14 sec 16 sec 18 sec 2...

Page 22: ...llic ware for cooking except where noted in the cooking guide Do not use any type of cookware with metallic trimming CAUSE REMEDY TROUBLE SHOOTING CAUTIONS 1 Check grounding before checking for trouble 2 Be careful of the high voltage circuit 3 Discharge the high voltage capacitor See page 2 1 4 When checking the continuity of the switches or of the high voltage transformer disconnect one lead wir...

Page 23: ...ly TROUBLE 1 The following visual conditions indicate a probable defective control circuit 1 Incomplete segments Segment missing Partial segment missing Digit flickering NOTE Slight flickering is normal 2 Colon does not turn on or blink 3 A distinct change in the brightness of one or more numbers in display 4 One or more digits in the display are not lighting 5 Display indicates a number different...

Page 24: ...switches and RELAY RY2 of P C B Assembly Check continuity of monitor switch with door closed Continuity No continuity Shorted contact at the primary switch Replace fuse primary monitor secondary switches and RELAY RY2 of P C B Assembly Check continuity of primary switch with door opened Continuity No continuity Malfunction of secondary switch Replace fuse primary monitor secondary switches and REL...

Page 25: ... Defective PCB assembly Loose connection Output is low Lower than 90 of rating voltage Normal Decrease in power source voltage with load Suggest customer contact local electric power utility co or qualified electrician Check the power source voltage Disconnect the wire leads from relay 2 and check on and off time with multitester Measure the output power Abnormal Abnormal Normal Defective PCB asse...

Page 26: ...uity relay 2 Operate the unit Defective PCB assembly Replace PCB assembly Replace high voltage transformer Defective high voltage capacitor Replace high voltage capacitor Abnormal normal Check high vol tage transformer Abnormal normal Check high vol tage capacitor Defective high voltage diode Replace high voltage diode Abnormal normal Check high vol tage diode Defective magnetron Replace magnetron...

Page 27: ...INTERIOR PARTS OVEN CAVITY PARTS DOOR PARTS LATCH BOARD PARTS CONTROL PANEL PARTS BASE PLATE PARTS SENSOR PARTS MAY000 MFL552 6 1 EXPLODED VIEW INTRODUCTION EV MODEL ...

Page 28: ... 6 2 DOOR PARTS 13581A 13551A 13213A 13552A 13536A 14026A 14970A EV ...

Page 29: ... 6 3 CONTROLLER PARTS 24781M 23550D 24510L 24970A 23551B 268711 WTP018 23551A EV ...

Page 30: ... 6 4 OVEN CAVITY PARTS 33390G WTT020 WSZ185 33112U 35889A 36549S WTP013 33052A Button Head Torx style 2 EV ...

Page 31: ... 6 5 LATCH BOARD PARTS WSZ085 WTT028 56912B 55262A 466001 466003 466001 43500A 43501A EV ...

Page 32: ... 6 6 INTERIOR PARTS 568771 WSZ002 WEB001 WTT028 56411A 56930V 56549F 54974S WTT037 55900A 54810C WTT028 50CZZH 56851D 56324A WEB001 948501 WSZ002 WSZ002 35012A 50FZZA 56201A 34930W EV ...

Page 33: ... 6 7 BASE PLATE PARTS 63302A WTT021 56170D WSZ002 65006B 63303A EV ...

Page 34: ... 6 8 SENSOR PARTS 56501A WSZ002 WTP004 54974T EV ...

Page 35: ......

Search results

Summary of Contents for LCRT2010ST

Reviews:

Related manuals for LCRT2010ST

Brands by name

Popular brands

LG LCRT2010ST, Service Manual

Search results

Summary of Contents for LCRT2010ST

Reviews:

Related manuals for LCRT2010ST

Brands by name

Popular brands