7 TIG WELDING OPERATION
0463 703 001
GB
-53-
7.2
AC TIG Welding
AC TIG Welding is used mainly for non-ferrous materials like aluminum. In AC TIG Welding the output current polarity is
switched between Electrode Positive (EP) and Electrode Negative (EN). In Rebel 205ic AC/DC the switching of output polarity
ranges from 25 – 400 Hz. EN polarity provides the welding action and EP polarity provides cleaning action.
Basic Mode:
In basic mode AC TIG has default settings as Pre-Flow = 0.8 sec, Post-Flow = 8 sec, Up-Slope = 0.5 sec, Down-Slope = 0.5
sec, Offset = 0, MIN = 5 A, Frequency = 120 Hz, and Balance = 70%.
User must be in Advance Mode to adjust these parameters.
Advanced Mode:
In advanced mode user has the ability to adjust the AC TIG settings as explained below.
1. Pre-Flow
2. Post-Flow
3. Up-Slope
4. Down-Slope
5. 2T/4T Mode
6. MIN (A)
7. Offset (A)
8. Frequency (Hz)
9. Amperage (A)
10. Balance (%)
MIN (A):
MIN current is used when in remote/foot-pedal mode. The default value is 5 A, user can adjust this value up to the
user set weld current to establish the lower limit.
Up-Slope
and
Down-Slope
settings are adjustable only in non-remote/non-foot-pedal mode.
Frequency (Hz):
Frequency is the number of times the AC TIG Arc switches between EP and EN in one second. Frequency
in Rebel 205 AC/DC machine varies from 25 – 400 Hz with a default value of 120 Hz. Frequency helps in narrowing the
weld bead and focus the arc in special application. Higher frequencies narrows the weld bead, has more focused arc and
increases the arc stability. In other words the arc cone is much tighter at 400 Hz and focused at the same spot the tungsten
electrode is pointing than the arc cone operating at 60 Hz.
Balance (%):
Main Screen and lower right encoder is used to adjust the Balance (%) in AC TIG advanced mode. Balance lets
you control the arc width, heat, and cleaning action etc.
Benefits of increasing the balance (i.e., increasing the EN portion of the AC TIG waveform):
•
Achieve greater penetration
•
Helps in increasing travel speeds
•
Helps in narrowing the weld bead
•
Helps in increasing the tungsten electrode life and reduces balling action
•
Reduces the size of etched zone for improved cosmetics
1
2 3 4
5
6 7 8
9
10
