Lincoln Electric IM520-B manual Advanced TIG Welding Features, AC Wave Balance and Auto Balance

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OPERATION

10.Press and release the Arc Start Switch, and set the gas flow meter. The welder is now ready for welding.

11.Position the tungsten electrode at the start of the weld at a 65 to 75 angle with the horizontal so that the electrode is approximately 1/8” (4mm) above the work piece. Press the Arc Start Switch. This opens the gas and water valves to automatically purge air from the hose and torch. After a 0.5 second preflow time, the high frequency becomes available to strike the arc.

12.Hold the Arc Start Switch or Amptrol down until an arc is established. If using an Amptrol, read the section on Hand and Foot Amptrol Operation. Release the Arc Start Switch or Amptrol to stop the arc and start the Afterflow timer. After the Afterflow time has expired, the gas and water valves will close. To make another weld, repeat steps 11 and 12.

TIG WELDING SEQUENCE OF OPERATION (4-Step Mode)

1.Connect an Arc Start Switch to the Remote Receptacle.

2.Turn the welder, gas supply and water supply (if so equipped), on. The Control Panel Display and red LEDS will illuminate when the power is on.

3.Select the TIG 4-Step Weld Mode.

4.Select the Local current control. Set the output current using the Amps Up/Down keys. The output current setting will be displayed on the Ammeter. On later version machines, remote control is also available in TIG 4- Step mode on codes 10022 and higher utilizing ROM version S21228-4 and higher provided that the remote control used has separate Arc Start and Output Control mechanisms.

5.Select Continuous High Frequency if welding with AC polarity, or Start Only High Frequency if welding with DC- polarity. High Frequency Off can be used for scratch start welding.

6.Select AC or DC- electrode polarity. See Table 2.

7.If welding with AC polarity, select Auto Balance™. This gives the optimum ratio between cleaning and penetration, automatically adjusted for the output current. If manual adjustment of the AC Wave Balance is desired, select Manual Balance, and adjust the wave balance with the Cleaning and Penetration keys. See the Advanced Features section for more information on setting and using the AC Wave Balance.

8.Select TIG Pulser On or Off. If the TIG Pulser is on, adjust the pulse frequency with the Pulses Per Second Up/Down keys. See the Advanced Features section for more information on setting and using the TIG Pulser.

9.Set the Afterflow time with the Seconds Up/Down keys. Afterflow time provides shielding gas flow (and cooling water, if used) after the weld. Use short Afterflow times with low currents and small tungstens, long afterflow times at high output currents with large tungstens.

10.Press and release the Arc Start Switch, and set the gas flow meter. The welder is now ready for welding.

11.Position the tungsten electrode at the start of the weld at a 65 to 75 angle with the horizontal so that the electrode is approximately 1/8” (4mm) above the work piece. Press the Arc Start Switch. This opens the gas and water valves to automatically purge air from the hose and torch. After a 0.5 second preflow time, the high frequency becomes available to strike the arc.

12.Hold the Arc Start Switch down until an arc is established. The arc will start at a low current value. Release the Arc Start Switch. At this point, the Square Wave TIG 255 will quickly ramp up to the welding current, and the weld will continue indefinitely. Press the Arc Start Switch a second time to initiate a 5-second downslope. The current will go down to a crater fill current that is equal to 25% of the welding current. Release the Arc Start Switch to stop the arc and start the Afterflow timer. After the Afterflow time has expired, the gas and water valves will close. To make another weld, repeat steps 11 and 12.

ADVANCED TIG WELDING FEATURES

AC Wave Balance and Auto Balance™

AC Wave Balance is a feature unique to square wave TIG power sources. It is active only in AC TIG mode. It controls the amount of positive and negative current in the AC output.

The Square Wave TIG 255 allows the operator to select Auto Balance™. This selection provides automatic adjustment of the AC Wave Balance; it is suitable for most welding conditions. Auto Balance gives the ideal amount of cleaning and penetration, based on the welding current output.

Manual adjustment of the AC Wave Balance is also possible. Select the Manual Balance key, and the Balance setting will appear in the Momentary Display. Manual Balance settings vary from +5 (maximum cleaning) to -10 (maximum penetration). A setting of 0 yields a balanced output (equal amounts of cleaning and penetration). Use the following as a guide when setting the Balance manually:

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Square Wave TIG Safety Electric Shock can kill Welding Sparks can cause fire or explosion Précautions DE Sûreté Sûreté Pour Soudage a L’ArcPlease Examine Carton and Equipment For Damage Immediately Table of Contents Installation Stacking Safety PrecautionsSelect Suitable Location TiltingInput Connections Rear PanelOutput Connections TIG Torch ConnectionStick Electrode Cable Connection Operating Instructions Safety InstructionsOperation General WarningsOperation Work General Description Operational Features and ControlsDesign Features and Advantages Recommended Processes EquipmentWelding Capability LimitationsControls and Settings Control Panel KeysDisplay Case Front ControlsWelding Operation Hand and Foot Amptrol Accessory OperationRecommended Polarity Settings for TIG Welding TIG WeldingTIG Welding Sequence of Operation 2-STEP Mode Typical Current Ranges for Tungsten ElectrodesTIG Welding Sequence of Operation 4-Step Mode Advanced TIG Welding FeaturesAC Wave Balance and Auto Balance Overload Protection Auxiliary PowerStick Welding ALL MachinesInstallation of Field Installed Options AccessoriesOptions / Accessories Undercarriage FunctionMaintenance MaintenanceRoutine and Periodic Maintenance General Assembly Exploded View Troubleshooting How To Use Troubleshooting GuideProblems Possible Areas Symptoms Misadjustments Troubleshooting GuideRecommended Course of Action Troubleshooting Function Problems TIG Mode Problems TIG Welding Problems Troubleshooting Stick Welding Problems Wiring Wiring Diagram Wiring Diagram Square Wave TIG 255 Code 10451, 10452Need Welding Training? How To Read Shop DrawingsNew Lessons in Arc Welding Basic CourseWarnung PrecaucionAtenção Warnung Limited Warranty