R-Tech TIG 500 AC/DC, Руководство по эксплуатации

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As a general rule, increasing the frequency at a
given set of welding and background current the
heat input into the plate will increase.
4.5.3 For AC TIG Welding
AC TIG welding is commonly used for the
welding of Aluminium and Aluminium alloys.
The positive half cycle of the AC current assist
in the cleaning action required for successfully
welding Aluminium.
Zirconiated tungstens are used for the welding
and the size of the tungsten depends on the
current employed.
In the normal AC sine wave equal time is
spent in the positive and negative cycle of the
current.This delivers a balanced weld with good
penetration and a good cleaning action.(5).
AC balance control
In addition to increasing the welding current
in AC applications, a change in the penetration
or cleaning when welding can be achieved by
adjusting the AC Balance.
The AC balance (time spend in the positive
(maximum cleaning) or negative (maximum
penetration) can be adjusted by using the AC
balance control knob (16).
By adjusting the AC balance control knob from
20-100% progressively increases the time in
the positive side of the AC curve (higher heat
concentration in the non-consumable tungsten
electrode).
This has the result that the amount of
penetration is decreased.
With the AC balance control set at 20%, higher
currents can be used on thinner electrodes,
resulting in the use of smaller gas cups,
therefore increasing visibility and reducing gas
flows.