Lincoln Electric SVM114-C service manual Theory of Operation Section

Page 33

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Section E

TABLE OF CONTENTS

Section E

 

- THEORY OF OPERATION SECTION -

 

 

 

 

Theory of Operation

Section E

General Description

E-2

Control Circuit Operation

E-2

Input Power Circuit

E-2

Welding Current Circuit

E-2

Feedback and Control Circuits

E-3

Trigger Circuit

E-3

Optional Circuits

E-4

Contactor

E-4

Gas Solenoid

E-4

Protective Devices & Circuits

E-5

Overvoltage Shutdown

E-5

Motor Overload Shutdown

E-5

Control PC Board Fuses

E-5

FIGURE E.1 THEORY OF OPERATION BLOCK DIAGRAM

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ELECTRODE INPUT CABLE

TO WORK

SENSING LEAD

 

 

 

OPTIONAL

 

 

 

 

 

CONTACTOR

 

 

 

 

 

CONDUCTOR

GUN CABLE

 

 

 

BLOCK

 

 

COLD

 

 

M

 

GUN

 

OPTIONAL

O

HALL

TRIGGER

INCH

 

T

CONNECTOR

SWITCH

CONTACTOR

O

EFFECT

 

 

 

BOARD

R

MODULE

 

P

 

 

 

 

 

O S

 

 

 

 

 

L W

 

 

ARMATURE VOLTAGE

 

 

A I

VOLT

 

 

 

R T

 

 

 

 

I C

METER

CONTROL

RPM FEEDBACK

 

 

T H

 

 

 

 

 

 

 

Y

 

BOARD

 

 

 

WIRE FEED

 

RANGE

 

 

 

SWITCH

 

 

MODE SWITCH

 

 

 

 

 

 

 

 

 

 

WIRE SPEED

 

 

 

 

 

CONTROL

 

 

 

 

SOLENOID

GAS

 

 

 

 

PC BOARD

SOLENOID

 

 

 

 

EARLY MODELS ONLY - LATER MODELS HAVE CIRCUITRY

 

 

 

 

INCLUDED ON CONTROL BOARD

 

LN-25™

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Contents Semiautomatic Wire Feeder California Proposition 65 Warnings SafetyElectric Shock can kill Fumes and GasesCan be dangerous Welding and Cutting Sparks can Cause fire or explosion Cylinder may explode if damagedIii Sûreté Pour Soudage a L’Arc Précautions DE SûretéMaster Table of Contents for ALL Sections Installation Section Table of ContentsTechnical Specifications LN-25 InstallationWire Feed Speed CurrentrentPower Source Connection Safety PrecautionsGUN Cable Connection to Feeder INVERTEC, CV300 and Other Newer Lincoln Power SourcesWith CV Adapter For GMA GUN and CablesWeld Cable Connection Wire Feed Drive Roll and Guide Tube KitsElectrode Cable Connection Work Cable ConnectionLN-25 Operation Section Operation Welding CapabilityRead and Understand Entire Section Before Operating Machine Wire Feed Mode Switch Electrode Polarity SwitchWire Speed Dial and Range Switch LN-25 Instruments ControlsWork Clip Lead GAS Post PRE-FLOW Timers OptionalAWG Remote ARC Voltage Control OptionalLoading Electrode Sequence of OperationMounting 22 to 30 LB READI-REELCOILS Mounting 10 to 30 LB SpoolsIdle Roll Pressure Setting Loading Wire DriveGrooves READI-REEL Inside Cage Wires 6OPERATIONB-6Setting Constant Wire Feed Speed CV Mode Presetting Wire Feed SpeedSetting ARC Sensing Wire Feed Speed CC Mode Minimum Arc VoltsMaking a Weld Figure B.4 VV CC Wire Speed SettingProcedure AT END of Coil WeldingCylinder may explode if damaged Circuit Protection and Automatic Shutdown Overvoltage ShutdownMotor Overload Shutdown Accessories Section C Accessories SectionLN-25 Option Chart AccessoriesHow to use Table C.1 Table C.1Optional Accessories K434-1 GAS Flow Timer KITGAS Solenoid KIT K430-2 for Codes K432 Remote Control Cable Assembly K433 Power Source Remote BOXRemote Output Control Options and Control Cable Assemblies LN-25 Contactor KIT K443-1 for CodesK625, K626, K627 Remote Control Cable Assembly K439 Remote Extension Cable AssemblyK624-1 42V Remote Output Control Module K444, K444-1 or K444-2 Remote Voltage Control KITTo GUN Switch Connect Leads to Pins a and C Connector Must be Insulated in this AreaStyle a DIA. HoleMaintenance Section Maintenance Routine MaintenanceAdjusting Speed Sensor Module Calibration of LN-25 Wire Speed Dial LN-25 Theory of Operation Section Figure E.1 Theory of Operation Block DiagramTheory of Operation Input Power CircuitGeneral Description Control Circuit OperationTrigger Circuit Feedback and Control CircuitsContactor Optional CircuitsGAS Solenoid Later ModelsControl PC Board Fuses Protective Devices CircuitsLN-25 Troubleshooting and Repair Section HOW to USE Troubleshooting Guide 2TROUBLESHOOTING and REPAIRF-2PC Board Troubleshooting Procedures Troubleshooting and RepairFeeding Problems Feeding Problems Hall Effect Test Description GAS Solenoid Valve and Solenoid PC Board TestMaterials Needed For Codes below 10500 onlyScrew Wire Reel Retaining Collar Test ProcedureCase Door GAS Solenoid ValveFigure F.2 Solenoid Leads Troubleshooting and Repair 512 GAS Solenoid Valve and Solenoid PC Board Test624A 621 J11 PC Board for K430 GAS Solenoid KITLN-25 For Codes Above 10500 only GAS Solenoid Valve and Control PC Board TestFigure F.5 Control BOX Cover Removal For Codes Above 10500 onlyFigure F.6. Solenoid Leads Solenoid LeadsControl PC Board Solenoid Circuitry Test Figure F.7. Applied Voltage Polarity667 555 691 621 500 512 690 G3425LN-25 Hall Effect Module Test Hall Effect Module Test G2196 539 541 500539 G1757 Figure F.11 Control PC Board Codes Above LN-25 Wire Drive Motor Test Drive Motor Lead IN-LINE Connector Hall Effect Module Contactor & Contactor PC Board Test Contactor & Contactor PC Board Test Contactor Test ProcedureContactor Coil Leads S2096328TROUBLESHOOTING and Repair F-28 Contactor PC Board Test667 J14 LN-25 Tools Required Contactor PC Board ReplacementRepair Procedure Contactor PC Board Replacement33TROUBLESHOOTING and Repair F-33 Figure F.17 Control PC Board Replacement Figure F.21. Control PC Board Codes 9812 and below Control PC Board ReplacementJ14 Figure F.22. Plug Locations for L12253- Control BoardFigure F.24. Control Board Replacement PC Board Screw For Codes below Contactor ReplacementContactor Replacement 40TROUBLESHOOTING and Repair F-40For Codes Above Figure F.26 Phillips Head Screwdriver Wrench Pliers Purge Switch Leads Solenoid Plug J11 Present ReplacementGAS Solenoid Valve AND/OR Solenoid PC Board if GAS SolenoidFigure F.29. Solenoid Assembly Wiring Codes 9812 and below Figure F.31. GAS Solenoid Assembly for Earlier Codes Phillips Head Screwdriver Wrench Slot Head Screwdriver Drive Motor and Gearbox Replacement and Access to 48TROUBLESHOOTING and Repair F-48Hall Effect Module Mylar Insulation Electrode CableG1757 Figure F.34. Drive Motor Replacement Retest After Repair LN-25 Table of Contents Electrical Diagrams Section Electrical DiagramsOptional 42 Volt Remote Output Control Wiring Diagram Above Code 11140 G4679Wiring Diagram Code 10556 Thru 10500 L10925 Wiring Diagram Code 10100 Thru 10500 L9644 Wiring Diagram below Code 9900 L7545 LN-25 Across the ARC Model Schematic Complete Machine Codes Above 11140 G5366Schematic Complete Machine below Code 9900 only G1833 Schematic Control PC BD Above Code 11140 G4616-5 Schematic Control PC BD Code 10556 Thru 10558 G3424-3 Schematic Control PC BD Code 10100 Thru 10500 G2194 PC Board Assembly Control Abovr Code 11140 L12253-3 L12253L12253-3 G3425 PC Board Assembly Control Code 10556 Thru 10558 G3425-3PC Board Assembly Control Code 10100 Thru 10500 G2196-1 LN-25 Control PC Board Assembly Control below Code 9900 G1757-6Contactor Schematic Contactor PC BD Above Code 10500 M10965Schematic Contactor PC BD Code 10100 Thru 10500 M17621 Electrical Diagrams Electrical Diagrams L10863 PC Board Assembly Contactor Above Code 10500 L10863-1PC Board Assembly Contactor Code 10100 Thru 10500 L9670-1 PC Board Assembly Contactor below Code 9900 L9185-2
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