Figure F.11 Control Board Mounting | Lincoln Electric SVM170-A

Return to Section TOC

Return to Section TOC

Return to Master TOC

Return to Master TOC

F-39	TROUBLESHOOTING AND REPAIR	F-39
	CONTROL PC BOARD REMOVAL AND REPLACEMENT (continued)

FIGURE F.11 — CONTROL BOARD MOUNTING.

TOOL

TRAY

MOUNTING PC CONTROL

STANDOFF BOARD

NOTE: TOP COVER SHOWN

REMOVED FOR CLARITY.

Return to Section TOC

Return to Section TOC

Return to Master TOC

Return to Master TOC

4.Ensure a static electricity grounding strap is used before handling the con- trol PC boards.

5.Carefully remove the control PC board from the mounting standoffs.

6.Lift the control PC board straight up and out from the machine.

7.When re-installing the control PC board carefully secure board to mounting standoffs.

8.Install all plug connectors previously removed from the control PC board.

9.Install the tool tray and close the side panels.

POWER MIG 255C

Image 79

Lincoln Electric SVM170-A service manual Figure F.11 Control Board Mounting

Contents

Power MIG 255C California Proposition 65 Warnings Safety Electric Shock can kill Iii Welding Sparks can cause fire or explosion Sûreté Pour Soudage a L’Arc Précautions DE Sûreté Master Table of Contents For ALL Sections Table of Contents Installation Section Installation Technical Specifications Power MIG 255C Location Safety PrecautionsUncrating the Power MIG 255C Input POWER, Grounding and Connection Diagrams Installation Figure A.2 Triple Voltage Machine Input Connections Auxiliary Power Receptacles GUN and Cable InstallationShielding GAS Operation Table of Contents Operation Section Wear eye, ear and body protec- tion OPERATIONB-2 Limitations Product DescriptionRecommended Processes and Equipment Welding Capability Wire Drive Roll Wire Size Conversion PartsDescription of Controls Wire Reel Loading Readi REELS, Spools or Coils Procedure for ChangingDrive and Idle Roll Sets To Start the Welder Feeding Wire ElectrodeIdle Roll Pressure Setting Wire Drive Configuration Figure B.4 Making a Weld When Timer Option is not installedInstructions to Enter Slow RUN-IN Instructions to Enter Fast RUN-IN Input Line Voltage Protection Avoiding Wire Feeding ProblemsWire Feed Overload Protection FAN Control Overcurrent Protection Welding Thermal Overload Protection Table of Contents Accessories Section Accessories Dual Cylinder Mounting KIT K1702-1 Drive Roll KitsMagnum GUN Connection KIT K363P READI-REEL Adapter Spool GUN Operating Instructions for Timer KITConnecting the Spool GUN to the Power MIG 255C K1738-1 Spool Gun Hanger Accessory Making a Weld with the Magnum SG Spool GUN Making a Weld with the Prince XL Spool GUN SG Spool Gun Wire Feed Speed Power MIG Table of Contents Maintenance Section Maintenance Liner Removal and Replacement GUN Tubes and Nozzles General MaintenanceGUN Cable Cleaning Contact TIP and GAS Nozzle Installation Table D.1 GUN Handle Disassembly English Metric Description MAINTENANCED-4 Theory of Operation Table of Contents Theory of Operation Section Main Transformer Input Line Voltage Feedback Control Output Rectification Figure E.4 Constant Voltage Output Constant Voltage Output Feedback Wire Drive Motor Thermal and Overload Protection Wire Feed Overload Protection Figure E.6 SCR Operation SCR Operation Power MIG 255C Table of Contents Troubleshooting and Repair Section Troubleshooting and Repair HOW to USE Troubleshooting Guide 2TROUBLESHOOTING and REPAIRF-2 PC Board Troubleshooting Procedures Output Problems Troubleshooting Guide Toxic. Avoid contact with any Problems Possible AreasSymptoms Misadjustments Course of Action Trolyte in these capacitors is Perform the SCR Rectifier Function Problems Wire Feeding Problems Welding Problems Welding Problems Materials Needed Test ProceduresMain Transformer Test Test Description ON/OFF Power Switch will be hot during these tests Test Procedure 16J5 8J5 115VAC 206 3J5 Rectifier Diode Bridge Test Figure F.2 G3521 Rectifier Diode Bridge Location 16TROUBLESHOOTING and REPAIRF-16 354 206 36 VDC 208 206 28 VAC 209 Power MIG 255C Static SCR Rectifier Assembly Test Static SCR Rectifier Assembly Test Active SCR Rectifier Assembly Test Power MIG 255C Active SCR Rectifier Assembly Test Active SCR Rectifier Assembly Test Figure F.7 Location Leads X2 Figure F.8 Wire Drive Motor and Tachometer Feedback Test 4J1 Wire Drive Motor and Tachometer Feedback Test 515B 206B 15 VDC 5J1 1J1 Test for Supply Voltage to Tachometer 555 206B To 3.5 VDC 6J1 1J1 Test for Feedback Voltage to Control Board Volts Normal Open Circuit Voltage Waveform Typical Output Voltage Waveform Machine Loaded Machine Loaded to 250 Amps AT 26 VDC Scope Settings Machine Loaded to 220 Amps AT 22 VDC Scope Settings Troubleshooting and Repair Typical SCR Gate Voltage Waveform Power MIG 255C Control PC Board Removal and Replacement Component Replacement ProceduresDescription Procedure Removal and Replacement Figure F.11 Control Board Mounting Power MIG 255C Wire Drive Assembly Removal and Replacement Wire Drive Assembly Removal and Replacement Procedure Power MIG 255C SCR Output Rectifier Removal and Replacement SCR Output Rectifier Removal and Replacement Figure F.15 Right Heat Sink Lead Disconnection Power MIG 255C Capacitor Bank Removal and Replacement Capacitor Bank Removal and Replacement Main Transformer and Output Choke Removal and Replacement Main Transformer and Output Choke 52TROUBLESHOOTING and REPAIRF-52 TOC Power MIG 255C FAN Motor Assembly Removal and Replacement FAN Motor Assembly Removal and Replacement Input Volts/Hertz Wire Speed RangeRetest After Repair Open Circuit Voltage Power MIG 255C Section G-1 Electrical Diagrams Section Wiring Diagram Entire Machine Code 11192 L12464 Electrical Diagrams Wiring Diagram Entire Machine Code 11218 L12506 Schematic Entire Machine G4752 Schematic Control PC Board G4823-2D1 Sheet Electrical Diagrams Electrical Diagrams Item Used with QTY Part Number Description PC Board Assembly Control G4824-2D1 Powermig Schematic Display PC Board L10951 Lincoln Electric CO PC Board Assembly Display L10952 SVM Error Reporting Form