7 TIG WELDING OPERATION
0463 703 001
GB
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Benefits of decreasing the balance (i.e., increasing the EP portion of the AC TIG waveform):
•
Better cleaning action to remove heavier oxidation on the work plate
•
Minimizes penetration which help prevent burn-through on thin materials
•
Widens the bead profile and helps in catching both sides of the joint
NOTE!
Decreasing the balance to a lower value at a particular weld current will have more
balling action on the tungsten, which will reduce the tungsten electrode life and may
lose arc stability, so care must be taken when adjusting the balance too low.
Offset (A):
Offset feature in AC TIG is used to vary the EP or EN currents to have better cleaning or better penetration
respectively without adjusting the balance (duty) and/or user set current. Offset gives the user ability to have a narrower
bead with deeper penetration and no visible cleaning action or wider bead with less penetration and clear visible cleaning
action based on which direction the Offset is adjusted.
In advanced AC TIG mode, the user can adjust the Offset parameter which will range from - (UserSetCurrent – MIN) to +
(UserSetCurrent – MIN). When using a foot petal, the set value of MIN current affects the usable Offset range. Example, if
UserSetCurrent is set to 104 A then the Offset adjustable range is from -99 A to +99 A, because MIN current is 5 A and add-
ing 5 A to 99 A results in 104.
Another example; in the case of Offset set to +15 A with a user set current of 104 A, the weld current drives to EP = 119 A
and EN = 89 A as shown in the pictures below.
