Lincoln Electric invertec v205-t Operator's Manual page 17

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5. Output / Parameter Adjust Knob- Allows you to
continuously adjust the current both in TIG and in
Stick welding. Allows you to change the value, shown
on "Digital Display Item 6", of the parameter selected
with "Setup/Parameter Item 4".
6. Digital Display - displays current values for each
mode or welding parameter.
7. Local/Remote push button - Selects the welding
current adjusting system:
• from front panel
• from remote control
The LED beside the symbol confirms the selection.
8. Tig Trigger Sequences -
For the V205-T AC/DC, TIG welding can be done in
either the 2-step or 4-step mode which is selected
with the Trigger Mode Push Button.
2-Step Sequence
With the Trigger Mode switch in the 2-step position,
the following welding sequence will occur.
1. Press and hold the Arc Start Switch to start the
sequence.
The machine will open the gas valve to start the flow
of the shielding gas. After a 0.5 second preflow time,
to purge air from the torch hose, the output of the
machine is turned ON. At this time the arc is started.
After the arc is started the output current will be
increased to the welding current. This increase, or
upslope, is presettable. The default is 5 seconds.
2. Release the Arc Start Switch to stop welding.
The machine will now decrease the output current at
a controlled rate, or downslope time, until the
Start/Crater current is reached and the output of the
machine is turned OFF. The downslope time is
adjusted by the Downslope Parameter.
After the arc is turned OFF, the gas valve will
remain open to continue the flow of the shielding
gas to the hot electrode and work piece. The dura-
tion of this postflow shielding gas is adjusted by the
Postflow Parameter.
Possible variations of this standard sequence is
shown in (2 step diagram 1).
OPERATION
It is possible to press and hold the TIG torch trigger a
second time during downslope to restart. After the trig-
ger is pressed the output current will increase to the
welding current. This operation is shown in (2 step
diagram 2).
4-Step Sequence
With the 4-step Selected, the following welding
sequence will occur.
1. Press and hold the Arc Start Switch to start the
sequence.
The machine will open the gas valve to start the flow
of the shielding gas. After a 0.5 second preflow time,
to purge air from the torch hose, the output of the
machine is turned ON. At this time the arc is started.
After the arc is started the output current will be at
the Start/Finish current. This condition can be main-
tained as long or as short as necessary.
If the Start/Finish current is not necessary, do not
hold the TIG torch trigger as described at the begin-
ning of this step. Instead, quickly press and release
the trigger. In this condition, the machine will auto-
matically pass from Step 1 to Step 2 when the arc is
started.
2. Release the TIG torch trigger to start the main part
of the weld.
V205-T AC/DC TIG
2 STEP DIAGRAM 1
2 STEP DIAGRAM 2
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