Full Product Manual

35
TERMS RELATED TO DC TIG FUNCTIONS
Arc Start Type. There are two basic forms of Arc starting that may be selected in manual mode, The user may select from either
High Frequency (touchless) arc starting or Lift Start (Lift Arc) . High Frequency start sends an HF impulse to the torch tip to jump
the gap between the Tungsten and the workpiece which establishes a circuit path for the welding arc to follow and ignite. Lift Start
which uses the torch switch or foot pedal to send a low current to the Tungsten tip. Once the tip of the Tungsten is touched quick-
ly to the work and raised up in a seamless motion, the welder senses the contact and sends full current through to the tip as it
breaks contact with the work, igniting the arc. (See instructions on TIG arc starting later in this manual.)
Amps. (A) Amps are the measurement of the “pressure” of the electricity. Depending upon wave form, the display may read lower
while welding than what is set, because the hall effect sensor measures and reports the average Amperage of a wave form, and not
the peaks. This includes Pulse Amperage as it reports an average Amp value. Changing the Wave-form or Changing the Pulse
settings affects the average Amperage. NOTICE: When the foot pedal mode is activated, the unit will display selected maximum
Amperage for a few seconds before defaulting to display the minimum welding Amperage. This is because the Amperage signal at
the foot pedal is at the minimum position. When the foot pedal is pressed, or the torch slider is increased, the display will continue
to reflect the Amperage dictated by the position of the pedal/slider. To recall the selected maximum Amperage, tap briefly on the
pedal, or slightly rotate the top right control knob. In 2T or 4T mode, the selected amperage will continue to display until the arc is
struck. After that the Amp display displays actual amp output, which may vary slightly from the preset Amperage.
Control. The Control setting governs the function of the torch switch and foot pedal. The control offers several modes which in-
clude 2T, 4T, Pedal, 2T Finger and 4T Finger. The Pedal mode allows the unit to be controlled by the foot pedal or a torch slider
or similar amptrol. 2T mode and 4T mode offer two modes used with the torch switch that is included with the TIG torch. This is
used to control the torch cycle through preset functions of Pre/Post Flow, Up/Down Slope, Start/End Amps. In 2T mode, the
torch switch is simply pressed and held to cycle the torch. Once arc termination is desired, the switch is released. In 4T mode,
the Torch trigger is held down to start the pre-flow and initiate the arc at the “Start Amp” setting. The switch is then released and
the unit begins up-slope until it reaches the welding current. The weld is continued without the switch being pressed. Once the
weld is nearing nish, the torch switch is once again pressed and held to down slope to the “End Amp” setting. Then the torch is
released to terminate the arc and begin post flow. The addition of the Finger 2T and 4T is simply a type of amptrol torch which
utilizes separate switches along with an amp control mounted on the torch. Rather than a slider which has the on/off switch built
into the movement like a foot pedal would have, the switch is independent from the potentiometer. (In the Power-Set mode this is
also referred to as “Remote” when selecting a start type which combines start type and control type together.)
Crater. The weld crater is the sunken area left at the end of the weld where the weld pool solidied. This divot is detrimental to
welds and cause cracking or create a point of weld stress as the weld metal tends to shrink at this point. The crater should be
lled before terminating the arc. In best practice, this is done during the down-slope stage of the weld cycle.
Down-Slope. During the weld cycle, the machine Amp output may be gradually decreased as the crater is lled. The amount of
time set determines the crater ll time that you have available. The Down-Slope reduces the Amps slowly until it reaches the End
Amp setting. Down-Slope time is not always necessary, particularly during basic 2T operations such as tacking. Set Down-Slope
to 0.0 when not needed in 2T mode. It is manually signaled when the torch trigger is pressed and held for the second time in 4T
mode. NOTICE: Down-Slope time should not be used in Foot-Pedal mode. Set Down-slope time to 0.0.
End Amps. The End Amp function is the nal Amp setting of the weld cycle. This is the nal current that is set before the arc is
set to terminate. The End Amp setting can be used with the foot pedal or the torch switch. However, for best tail-off of the arc
with the foot pedal, the End Amp setting should be set to the lowest value possible. If a large tungsten is used, however, a higher
End Amp setting may be required to terminate the arc cleanly. Larger diameter Tungstens make starting and stopping an arc more
difcult, so be sure to offset this issue with a higher End Amp setting, of at least 5 to 10 amps.
Foot Pedal. The foot pedal is used to start the arc and control the amperage throughout a preset range. This can also be accom-
plished with the use of the NOVA torch slider which can be ordered through Everlast. The slider switch acts the same as a foot
pedal, but is mounted directly to the torch with a set of Velcro straps. This allows quick removal if needed.
Post-Flow Time. Post Flow time is the amount of time that the shielding gas flows after the weld is terminated. This helps to form
a protective pocket of shielding gas around the still molten, or cooling weld to prevent harmful oxygen from the atmosphere from
entering the weld and oxidizing it. Post-Flow time is also used to cool the torch head and consumables. Long weld times require
more Post-Flow Time, but for small welds, 1 second of post-flow for every 20 amps set is usually sufcient.
Section 2 Setup Guide
UNDERSTANDING DC TIG FUNCTIONS