Longevity WeldAll 160PI/200PI/250PI - Manual (Page 20)

160PI/200PI/250PI AC/DC Series IGBT Machines
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PULSE CURRENT. (Pulse Current 5-### amps): Only active in pulse mode. This Set’s the pulse peak (high)
amperage of the pulse cycle. Select the peak amperage with this control to achieve the maximum amperage
requirements for the high pulse cycle. The amperage change will be reflected on the digital display.
PULSE FREQUENCY. (Pulse Frequency 0.5-25 cycles per second): Only active in pulse mode. The TIG
pulse frequency controls the number of pulse cycles per second (Hz). Changing the frequency sets the duration
of each pulse cycle, so the lower the frequency the longer the pulse. A higher pulse frequency will give a shorter
pulse cycle. This allows for fine control of heat input into the base metal.
PULSE WIDTH (0.1 to 0.9 or 10-90%): Only active in pulse mode. This TIG pulse control adjusts the relative
amount of time the pulse spends in the peak (high) current stage during a pulse cycle. For example, a control
knob setting of 90% or .9 will give you 90% of the time in the peak (high) current stage and 10% in the base
(low) current stage of the pulse cycle. Note: The Pulse width does not control the overall length of the pulse.
The Pulse frequency sets the cycle length, thereby setting the overall length of each leg of the cycle.
DOWN SLOPE (0-10 seconds): The Down slope time controls the end cycle of the weld by slowly bringing
down the welding current. The down slope helps prevent weld cracking and hole formation in the crater, as the
end of the weld is reached and the torch trigger is released.
AC FREQUENCY. (Alternating Current Frequency 20-100 cycles per second): Only active in AC mode. This
AC TIG & Stick control adjusts the arc frequency. Setting high frequency narrows the welding arc making it
more directional and increasing penetration. Lower frequency widens the arc and shallows the welding puddle.
AC BALANCE (30-70%): Only active in AC mode. This AC TIG & Stick control determines the amount of
time the AC cycle spends in DCEN (Direct Current Electrode Negative -) or DCEP (DC Electrode Positive +).
More DCEP is preferred for cleaning oxidation, particularly in aluminum. More DCEN is preferred for better
penetration and faster travel speed. A 50% setting equalizes the time spent in both. 30% setting is a good
starting point. A higher AC balance setting will clean the weld more but put more heat into the electrode,
reduce this setting if you melt the electrode. For higher AC balance settings use a thicker electrode to keep it
from melting.
POST FLOW (1-25 seconds): This timer controls the flow of shielding gas after the TIG weld arc is
terminated. Not enough post flow can cause weld contamination or torch overheating. During plasma cutting,
Post Flow allows for cooling air to flow after terminating the arc. Keep the TIG torch in position over the weld
until the post flow ends. Five seconds for plasma cutting and 5 to 10 seconds for TIG welding is a
recommended starting point.
4T/2T SWITCH: This switch select is for the control of the TIG weld cycle via the TIG torch trigger. In the 2T
mode, simply touch and hold the trigger to start the arc and continue holding while welding. Release the trigger
to finish. In the 4T mode each push of the trigger toggles between on and off (push and release trigger once to
start, push and release once to stop welding).
PRESSURE REGULATOR: To adjust the pressure regulator, pull the knob out to unlock. Turn the knob left
to decrease the Argon/air flow, or right to increase flow. Both pressurized air for plasma cutting and Argon gas
for welding are affected by this knob. Set regulator to approximately 75 psi. air pressure for plasma cutting.