Lincoln Electric V250-S service manual Troubleshooting & Repair

Page 95

Section TOC

Master TOC

F-63	TROUBLESHOOTING & REPAIR	F-63
	TROUBLESHOOTING & REPAIR

OUTPUT DIODE ASSEMBLY REMOVAL AND REPLACEMENT

(MACHINE CODES ABOVE 10150)

(continued)

Return to

Return to Section TOC

Return to Section TOC

Return to Section TOC

Return to

Return to Master TOC

Return to Master TOC

Return to Master TOC

6.Using 7/16” wrench remove the top and bottom mounting bolts and associated washers from the diode module to be replaced.

7.Using 1/8” Allen wrench remove the center socket head cap screw from the diode module to be replaced.

8.Carefully remove the diode module.

9.To install the new module first make sure the heat sink surface is clean and free of dirt.

10.Apply a thin even coating (.004 to

.010 IN.) of thermal compound Penetrox A13 (Lincoln E2529) to the bottom surface of the base plate. Keep the compound away from the mounting hole areas.

11.Apply a small amount of Loctite #271 (Lincoln E1777-1) to the first three threads of the socket head cap screw.

12.Start threading the top and bottom screws and associated washers by hand. Also start the center socket head cap screw and associated washer.

13.Run the center cap screw in by hand until it makes contact with the surface of the module. Do not torque down yet!

14.Tighten the top and bottom screws to between 5.0 and 10.0 IN-LBS.

15.Tighten the center cap screw to between 12 and 18 IN-LBS.

16.Further tighten the top and bottom screws to between 30 and 40 IN-LBS.

17.Connect the leads to the proper ter- minals and tighten the screws to between 30 to 40 IN-LBS. Do not stress the module terminals when making these connections.

18.Clear all leads and prepare unit for reassembly of wrap-around case.

INVERTEC V250-S

Image 95

Contents Invertec V250-S Safety Fumes and Gases can be dangerous Electric Shock can killARC Rays can burn Welding Sparks can cause fire or explosion Cylinder may explode if damagedSûreté Pour Soudage a L’Arc Précautions DE SûretéMaster Table of Contents for ALL Sections Table of Contents Installation Section InstallationThree Phase Technical Specifications Invertec V250-SThree Phase Single Phase Select Suitable Location Safety PrecautionsInput Connections Power Input Connection for 50/60 HZ Machines Input Voltage Reconnect ProcedureInput Fuse and Supply Wire Output Cables Remote Control ReceptacleOutput Connections Quick Disconnect PlugsInvertec V250-S Operation Gouging Sparks Safety InstructionsFigure B.1 Case Front Controls Controls and SettingsTIG Welding Constant Current ProcessesManual ARC Welding Stick AIR Carbon ARC CuttingThermal Protection Parallel OperationOverload Protection Invertec V250-S Table of Contents Accessories Section AccessoriesCable Plugs Options / AccessoriesRemote Controls Table of Contents Maintenance Section MaintenanceFigure D.1 Location of Input Filter Capacitor Terminals Input Filter Capacitor Discharge ProcedureFilter Capacitor Conditioning Routine MaintenanceFigure D.2 Location of Maintenance Components Theory of Operation Table of Contents Theory of Operation SectionInput Line Voltage General DescriptionFigure E.2 Protection and PRE-CHARGE Circuits Precharge and ProtectionFigure E.3 Main Transformer Main TransformerFigure E.4 Output Rectification and Control Output Rectification ControlOverload Protection Protection CircuitsInsulated Gate Bipolar Transistor Igbt Operation Maximum Output Pulse Width ModulationMinimum Output Troubleshooting & Repair Oscilloscope Warning HOW to USE Troubleshooting GuideBoard can be dam- aged by static electricity PC Board Troubleshooting ProceduresCourse of Action Possible Areas Recommended SymptomsPerform the Control Board Voltage Checks Possible AreasCapacitor Balance Test Troubleshooting & Repair Perform the Output Diode Test Welding Problems Invertec V250-S Materials Needed Auxiliary Transformer TestTest Description Auxiliary Transformer Test Test ProcedureTable F.1 Auxiliary Transformer Test Points Auxiliary Transformer TestInvertec V250-S Input Rectifier Test Input Rectifier Test Test ProcedureTest Point Terminals Analog Meter X10 Range Table F.2 Input Rectifier Test PointsInvertec V250-S Power Board Resistance Test Test Description Power Board Resistance TestTable F.3 Power Board Resistance Test Points Power Board Resistance TestInvertec V250-S Output Diodes Test Figure F.4 Machine Output Terminals Output Diodes TestInvertec V250-S Diode Modules Power Board Voltage Test Figure F.8 Plug J6 on Power Board Power Board Voltage TestTest Conditions Table F.4. Power Board Voltage Test PointsAcceptable Test Description Invertec V250-S Control Board Voltage Test Figure F.9 Plugs J1-J5 on Control Board Control Board Voltage Test18VAC Table F.5. Control Board Voltage Test PointsInvertec V250-S Protection Circuit Test Figure F.10 Control Board Plug J2 Test Points Protection Circuit TestProtection Circuit Simplified Invertec V250-S Capacitor Balance Test Capacitor Balance Test Figure F.12 Power Board and Capacitor Test LocationsTable F.6 Capacitor Voltages Invertec V250-S Control Board Removal and Replacement V250S Control Control Board Removal and ReplacementProcedure Power Board Removal and Replacement Figure F.14 Power Board Lead Locations Power Board Removal and ReplacementPower Board Replacement Procedure Invertec V250-S Matched Parts Filter Capacitor Removal and ReplacementFigure F.15 Heatsink/Power Board Removal Filter Capacitor Removal and ReplacementPerform Power Board Replacement Procedure in this section Invertec V250-S Input Rectifier Bridge Removal and Replacement Figure F.16 Input Rectifier Lead Locations Input Rectifier Bridge Removal and ReplacementTroubleshooting & Repair Invertec V250-S Materials Needed Snubber Resistors Locking Tabs Invertec V250-S Wrench Allen type wrench Torque wrench Mounting Bolts Diode Modules Bolted Connections Troubleshooting & Repair Invertec V250-S Main Transformer Removal and Replacement Machine Codes below T3 Current Transformer Main Transformer Main Transformer Secondary Leads Figure F.22 Main Transformer Mountings Clear all leads and secure for case wrap-around assembly Invertec V250-S Main Transformer Removal and Replacement Machine Codes Above Figure F.23 Main Transformer Right Side Figure F.24 Main Transformer Left Side Figure F.25 Main Transformer Mountings Troubleshooting & Repair Invertec V250-S Input Idle Amps and Idle Watts Maximum Acceptable Output AT Minimum Output SettingsMinimum Acceptable Output AT Maximum Output Settings Retest After RepairInvertec V250-S Electrical Diagrams Invertec V250-S Invertec V250S Wiring Diagram Codes 10102Return to Section Wiring Diagram Codes 10187G2666 Control PC Board G2666 LayoutPower P.C. BD. Asbly Power PC Board G2684 LayoutRelay Coils Control PC Board G2666 SchematicFrom Control BD Power PC Board G2684 Schematic