Square Wave TIG | Lincoln Electric SVM100-A instruction

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SQUARE WAVE TIG 255

NOTES

G-5

Image 91

Lincoln Electric SVM100-A service manual Square Wave TIG

Contents

Square Wave TIG Fumes and Gases can be dangerous SafetyElectric Shock can kill ARC Rays can burn Welding Sparks can cause fire or explosion Cylinder may explode if damaged May be dangerous Electric and Magnetic Fields Sûreté Pour Soudage a L’Arc Précautions DE Sûreté Master Table of Contents for ALL Sections Installation Section Table of Contents Technical Specifications Square Wave TIG Installation Stacking Safety PrecautionsHigh Frequency Interference Protection Select Suitable Location Ground Connection Input ConnectionsInput Supply Connections Output Connections Reconnect ProcedureTIG Torch Connection Stick Electrode Cable Connection Table A.1 Operation Section Fumes and Gases OperationOperating Instructions General Warnings Section TOC Coolant Tion Output Polarity Do not Switch AC & DC Recti Fier Power SourceWhile Weld ING TIG Gtaw Single Phase Work Connec Recommended Processes and Equipment Design Features AdvantagesOperational Features and Controls General Description Limitations Welding Capability Control Panel Keys Controls and Settings Load Case Front Controls TIG Welding Guidelines Accessory Operation TIG WeldingTable B.1 Recommended Polarity Settings for TIG Welding Hand and Foot Amptrol Welding Operation Table B.2 Typical Current Ranges 1 for Tungsten Electrodes TIG Welding Sequence Operation 2-STEP ModeSquare Wave TIG 255 12/95 TIG Welding Sequence Operation 4-STEP Mode AC Wave Balance and Auto Balance Auxiliary PowerAdvanced TIG Welding Features ALL Machines Overload Protection Square Wave TIG Accessories Section Undercarriage Function AccessoriesOptions / Accessories Installation of Field Installed Options Maintenance Section Safety Precautions MaintenanceMaintenance Routine and Periodic Maintenance Figure D.1 General Assembly Exploded View Square Wave TIG Theory of Operation Section Power Supply Block Logic Diagram Input Line Voltage and Main Transformer Theory of Operation Output Rectification and Feedback Control High Voltage / High Frequency Circuit DC Welding Circuit DC Welding Output AC Welding Circuit AC Welding Output SCR Operation Square Wave TIG SCR Operation Thermal Protection Troubleshooting & Repair Section HOW to USE Troubleshooting Guide 1TROUBLESHOOTING & Repair PC Board Troubleshooting Procedures Troubleshooting & Repair Output Problems Troubleshooting Guide 12/95 Square Wave TIG Troubleshooting & Repair Possible Areas of Misadjustments Problems SymptomsRecommended Course of Action Function Problems Troubleshooting Guide Troubleshooting & Repair TIG Mode Problems Troubleshooting & Repair Troubleshooting Guide TIG Welding Problems Troubleshooting & Repair Stick Welding Problems Figure F.1 Control Board Connectors PC Board Connector Locations Test Description Control Transformer T2 Voltage TestMaterials Needed Control BOX Test Procedure Figure F.4 Control Board and Transformer Control Transformer T2 Voltage Test PROTECTION/SNUBBER Board Continuity Test PROTECTION/SNUBBER Board Continuity Test Table F.6 Square Wave TIG Figure F.6 PROTECTION/SNUBBER Board Test Points ARC Start Trigger Circuit Test ARC Start Trigger Circuit Test Figure F.9 PROTECTION/SNUBBER Board Test Points Static SCR Test Figure F.11 Protection Board Plug Locations Static SCR Test Active SCR Test Figure F.13 PROTECTION/SNUBBER Board Plug Locations Active SCR Test Silicon Controlled Rectifier Test Battery Test Scope Settings Normal Open Circuit Voltage Waveform DC Stick Mode Normal Open Circuit Voltage Waveform AC Stick Mode Normal Open Circuit Voltage Waveform DC TIG Mode Normal Open Circuit Voltage Waveform AC TIG Mode Machine Loaded to 200 Amps AT 50 VDC Typical Output Voltage Waveform Machine Loaded DC TIG Mode Machine Loaded to 50 Amps AT 26VAC AC TIG Mode Auto Balance onMachine Loaded to 200 Amps AT 46 VAC Typical SCR Gate Voltage Waveform Volts 5ms Volts 2ms Troubleshooting & Repair Tools Required FAN Motor and Blade Removal FAN Motor and Blade Removal Materials Required SCR Heat Sink Assembly Removal SCR Heat Sink Assembly Removal Input Idle Amps Retest After RepairRecommended Meters for Machine Output Tests Figure F.16 Transformer Lead Test Points Retest After Repair cont’d Electrical Diagrams Electrical Diagrams PTC1,PTC2 THERMISTOR-PTC,56 OHMS,90MA Control Board G2150 Control Board G2150 cont’d Square Wave TIG PROTECTION/SNUBBER Board L9255 CAPACITOR-CEMO,4700P,50V,10% Square Wave TIG Wiring Diagram Square Wave TIG 6 a 0 a 7 a 8 a 3 C Machine Schematic Square Wave TIG A C C T G2150 Y P a D Control Board Schematic Square Wave TIG 255 cont’d G2150 PROTECTION/SNUBBER Board Schematic Square Wave TIG 255 L9255 Keypad LED Board Square Wave TIG 255 L9212