Lincoln Electric SVM169-A service manual Electric Shock can kill

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SAFETY

 

 

 

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ELECTRIC SHOCK can kill.

3.a. The electrode and work (or ground) circuits are electrically “hot” when the welder is on. Do not touch these “hot” parts with your bare skin or wet clothing. Wear dry, hole-free gloves to insulate hands.

3.b. Insulate yourself from work and ground using dry insulation. Make certain the insulation is large enough to cover your full area of physical contact with work and ground.

In addition to the normal safety precautions, if welding must be performed under electrically hazardous conditions (in damp locations or while wearing wet clothing; on metal structures such as floors, gratings or scaffolds; when in cramped positions such as sitting, kneeling or lying, if there is a high risk of unavoidable or accidental contact with the workpiece or ground) use the following equipment:

Semiautomatic DC Constant Voltage (Wire) Welder.

DC Manual (Stick) Welder.

AC Welder with Reduced Voltage Control.

3.c. In semiautomatic or automatic wire welding, the electrode, electrode reel, welding head, nozzle or semiautomatic welding gun are also electrically “hot”.

3.d. Always be sure the work cable makes a good electrical connection with the metal being welded. The connection should be as close as possible to the area being welded.

3.e. Ground the work or metal to be welded to a good electrical (earth) ground.

3.f. Maintain the electrode holder, work clamp, welding cable and welding machine in good, safe operating condition. Replace damaged insulation.

3.g. Never dip the electrode in water for cooling.

3.h. Never simultaneously touch electrically “hot” parts of electrode holders connected to two welders because voltage between the two can be the total of the open circuit voltage of both welders.

3.i. When working above floor level, use a safety belt to protect yourself from a fall should you get a shock.

3.j. Also see Items 6.c. and 8.

ARC RAYS can burn.

4.a. Use a shield with the proper filter and cover plates to protect your eyes from sparks and the rays of the arc when welding or observing open arc welding. Headshield and filter lens should conform to ANSI Z87. I standards.

4.b. Use suitable clothing made from durable flame-resistant material to protect your skin and that of your helpers from the arc rays.

4.c. Protect other nearby personnel with suitable, non-flammable screening and/or warn them not to watch the arc nor expose themselves to the arc rays or to hot spatter or metal.

FUMES AND GASES can be dangerous.

5.a. Welding may produce fumes and gases hazardous to health. Avoid breathing these fumes and gases.When welding, keep your head out of the fume. Use enough ventilation and/or exhaust at the arc to keep

fumes and gases away from the breathing zone. When welding with electrodes which require special ventilation such as stainless or hard facing (see instructions on container or MSDS) or on lead or cadmium plated steel and other metals or coatings which produce highly toxic fumes, keep exposure as low as possible and below Threshold Limit Values (TLV) using local exhaust or mechanical ventilation. In confined spaces or in some circumstances, outdoors, a respirator may be required. Additional precautions are also required when welding on galvanized steel.

5.b. Do not weld in locations near chlorinated hydrocarbon vapors coming from degreasing, cleaning or spraying operations. The heat and rays of the arc can react with solvent vapors to form phosgene, a highly toxic gas, and other irritating prod- ucts.

5.c. Shielding gases used for arc welding can displace air and cause injury or death. Always use enough ventilation, especially in confined areas, to insure breathing air is safe.

5.d. Read and understand the manufacturer’s instructions for this equipment and the consumables to be used, including the material safety data sheet (MSDS) and follow your employer’s safety practices. MSDS forms are available from your welding distributor or from the manufacturer.

5.e. Also see item 1.b.

Mar ‘95

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PRECISION TIG 185

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Contents Precision TIG Safety Electric Shock can kill Welding Sparks can cause fire or explosion SafetySûreté Pour Soudage a L’Arc Précautions DE SûretéMaster Table of Contents for ALL Sections Installation Section Table of ContentsInput Single Phase only InstallationK2345-2 Input at Rated Output Model Height Width Depth WeightSelect Suitable Location Safety PrecautionsInput Connections TIG Torch Connection Input Reconnect ProcedureOutput Connections Connections for TIG Gtaw WeldingRemote Control Connection Work Cable ConnectionShielding GAS Connection Precision TIG Section B Operation SectionOperation Recommended Processes and Equipment Product DescriptionControl Functionality Controls and SettingsWelding in TIG Mode Operating StepsPulse TIG Control Benefits of the Precision TIG 185 Design Remote Control OperationRecommended Electrode Amperage Ranges Precision TIG Welding in Stick ModePrecision TIG Accessories Section Accessories Factory Installed OptionsTable C.1 K2348-1 Under-Storage Cart Field Installed OptionsPrecision TIG Section D Maintenance SectionMaintenance Routine and Periodic MaintenanceSpark GAP Adjustment Figure D.2 Location of Maintenance Components Return to Section TOC Section E Theory of Operation SectionInput Power Circuit Theory of OperationGeneral Description Figure E.3 Control Board and Output Feedback Control Output Rectification Feedback ControlFigure E.4 High Voltage/High Frequency Circuit High Voltage / High Frequency CircuitFigure E.5 DC Welding Current Generation DC Welding OutputFigure E.6 AC Square Wave Welding Current Generation AC Welding OutputFigure E.7 SCR Operation SCR OperationProtective Circuits Thermal ProtectionOverload Protection Section F Troubleshooting & Repair SectionHigh Voltage / High Frequency can damage test equipment Troubleshooting & RepairWorkstations PC Board Troubleshooting ProceduresCourse of Action Problems Possible Areas Recommended SymptomsPossible Areas Recommended Symptoms Problems Possible Areas Check the welding cables and or TIG Mode Problems Troubleshooting & Repair TIG Welding Problems Problems Possible Areas Electric Shock can Problems Possible Areas Recommended Symptoms Stick Welding Problems Test Description High Frequency Circuit Disable ProcedureFigure F.1 Spark GAP Assembly ProcedureT1 Transformer Test T1 Transformer Test Test ProcedurePrimary Windings Primary Voltages Return to Section Section TOCPrecision TIG Static SCR Test Static SCR Test Assembly Removal and Replacement Precision TIG Active SCR Test Active SCR Test Figure F.6 SCR Gate Locations Precision TIG AC TIG Mode Scope SettingsNormal Open Circuit Voltage Waveform DC TIG Mode AC Stick Mode DC Stick Mode Machine Loaded to 180 Amps AT 16VDC Typical Output Voltage Waveform Machine LoadedDC TIG Mode Machine Loaded to 180 Amps AT 26VDC DC Stick Mode 50 V/Div Precision TIG SCR Bridge Assembly Removal and Replacement Procedure Troubleshooting and RepairProcedure SCR Bridge AssemblyFront Panel Mounting Screws Figure F.9 Plug J2 on Control Board 42TROUBLESHOOTING & REPAIRF-42Replacement Procedure 43TROUBLESHOOTING & REPAIRF-43Precision TIG Polarity Switch Removal and Replacement Procedure Removal Procedure Polarity SwitchReplacement Procedure Precision TIG High Voltage Transformer Removal and Replacement Procedure Transformer Secondary Leads Precision TIG High Voltage TransformerFigure F.12 High Voltage Transformer Mounting Insulators Precision TIG Nutdriver Wrench Wire cutters Perform the SCR Bridge Assembly Removal Procedure Assembly Replacement Procedure Precision TIG Recommended Meters for Machine Output Tests Troubleshooting and RepairRetest After Repair Input Idle AmpsPrecision TIG Electrical Diagrams Section Precision TIG Wiring Diagram Entire Machine G4549G4588 Schematic Entire Machine G4588Schematic Control PC Board G4550-1B4-1 Schematic Control P.C. Board G4550-1B4-2 Schematic Control P.C. Board G4550-1B4-3 G4551 PC Board Assembly Control G4551-1SVM Error Reporting Form