LG Electronics GR-P227/L227 Explation for Micom Circuit, Explanation for PWB circuit

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EXPLATION FOR MICOM CIRCUIT

1. Explanation for PWB circuit

1-1. Power circuit

The power circuit includes a Switched Mode Power Supply (SMPS). It consists of a rectifier (BD1 and CE1) converting AC to DC, a switch (IC2) switching the DC voltage, a transformer, and a feedback circuit (IC3 and IC4).

Caution : Since high voltage (310 Vdc) is maintained at the power terminal, wait at least 3 minutes after unplugging the appliance to check the voltages to allow the current to dissipate.

Voltage of every part is as follows:

Part	VA1	CE1	CE2	CE3	CE4	CE5

Voltage	230 Vac	310 Vdc	16 Vdc	12 Vdc	16 Vdc	5 Vdc

(1) GR-P227/L227

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Contents Refrigerator Contents Page Specifications Front ViewRef No. GR-L227 Ref No. GR-P257 Ref No. GR-L257 Parts Identification Freezer Refrigerator compartment compartmentRef No. GR-P227/GR-P257EXTERNAL Filter Parts Identification Parts Identification HOW to Install Refrigerator How to Adjust Door Height of RefrigeratorBefore Installation How to Install Water PipeClass Shape and Spec Nomenclature Connection of Pipe Connector a and B Single Lever Type Faucet generalTwo Hands Type Faucet General TypeFilter Cleaning When customer uses bottled waterOutternal Filter Filter Fixation After installing water filter Replacement of water filterHow to Control the Amount of Water Supplied to Icemaker Confirm the amount of water supplied to the icemakerDoor Alarm Buzzer Mute Mode Display Power saving ModeMicom Function Monitor PanelExhibition Mode Description of FunctionOutside temperature display function LCD Back Light ControlLock function display button lock Filter condition display functionWhen ice maker does not operate smoothly Dispenser use selectionAutomatic ice maker Express FreezerMiracle Zone function Super freezingControl of variable type of freezing room fan Door opening alarm Control of M/C room fan motorDoors of freezing Or home barSequential operation of built-in product Failure Diagnosis Function Mode Operation Contents Remarks Test FunctionTest Mode 1 Status LCD Test Mode 2 Status LCD Function of dispenser and water dispenser built-inPower circuit Explation for Micom CircuitExplanation for PWB circuit GR-P227/L227Oscillation circuit Reset circuitGR-P227/L227/P257/L257 Load/dispenser operation, door opening circuit Load Driving CircuitLever Switch sensing circuit Measuring part Dispenser operation circuitDoor opening sensing circuit Temperature sensing circuit Short OpenOption designation circuit model separation function Switch entry circuitSeparation Connection Status Application Standard Stepping motor operation circuit Fan motor driving circuit freezer, mechanical area +5 C +9F 33 k Ω 56 k Ω JCR1 Main PCB Sensor resistance characteristics table Miracle Zone Stepping Motor / Display Operation Principle Harvest Mode Icemaking ModeFill/Park Position Water supply amount TableStage Items Indicator Remarks Defect diagnosis functionCircuit Trouble Shooting Trouble DiagnosisNot performed Evaporator by heating as Refrigeration Refrigeration Residual Refrigeration No cooling air circulation Is weak Fan does not work Recess Sounds Compressor compartment operating sounds Bad soldering Bad rivet contact Short Structure Door foam Appearance Sag Faults PowerProblems Causes Checks Measures Remarks Problems Causes Checks MeasuresTemperature Cooling Disconnected from the motor Refer to fan motor disassembly Defrosting failure Problems CausesMeasures Remarks Remove the parts and replace it Icing Discharging port of cooling air Sound Click Contraction of evaporator Sources Sound Burping It happens when refrigerant expands Odor Problems Symptom Causes Checks Measures Remarks MicomDriving circuits Motor damper Replace door switch Trouble Diagnosis Cooling Cycle Heavy Repair Items Unit Standards Purposes RemarksProcess Contents Tools Summary Of Heavy RepairPrecautions During Heavy Repair Items PrecautionsWhen replacing a drier When replacing a compressorPractical Work For Heavy Repair Inserting a capillary tubePipe Connection Vacuum SequenceCharging sequence Calculation of amount of refrigerant chargedStandard Regulations For Heavy Repair 12-0mmAsia / Middle-East Africa Brazing Reference DrawingsEurope & CIS / America Problems Checks and Measures Explain the principles of temperature changeSound depends on the installation location Explain general principles of soundsExplain the procedure and principles of ice maker operation Explain the flow of refrigerantExplain the characteriistics of moving parts Explain the principles of water supplied to dispenserMeasures for Symptoms on Temperature Check the temperature control button and set at strong Odor and FrostExplain the basic principles of food odor Explain the basic principles of frost formationOthers HOW to Disassemble and Assemble Remove a freezer doorHandle InsertTubeLineColletClip Assembly COVER, Dispenser Exploded View Ref No. GR-P227/GR-P257 Optional partRef No. GR-L227/GR-L257 Freezer Compartment Refrigerator Compartment Optional partMachine Compartment ICE & Water Part Dispenser Part No JD8999A