STAYER WELDING TIG AC/DC 190HF PULSED Mode D'emploi page 33

flux).
2. Gas discharge time after appearance of the electric arc (post-
flux).
3. Electric arc intensity at the initial intensity slope.
4. Electric arc intensity at the final intensity slope.
5. Increase time for the initial intensity slope.
6. Decrease time for the final intensity slope.
7. Consolidated welding intensity of the electric arc.
8. Pulse peak intensity of the welding arc.
9. Pulse base intensity of the welding arc.
10. Percentage of the pulse peak of the welding arc versus the
pulse base.
11. Pulse frequency of the welding arc.
12. Proportion of the negative half-wave of the alternating
welding current versus the positive half-wave.
13. Proportion of the negative half-wave of the alternating
welding current versus the positive half-wave.
14. Frequency of the polarity change of the alternating welding arc.
SETTING OF THE WELDING TYPE
The 4 modes are selected by pushing button 15.
1.- Shielded electrode
The machine operates as a standard electrode welding machine
where the functions for enhancement of welding Hot Start, Anti
Stick and adjustable Arc Force become activated.
2.- Standard TIG
The machine is programmed as TIG welding machine without
pulsed arc, in direct current 'DC' or alternating current 'AC'
(button 16).
3.- Pulsed TIG
The four pulsed-arc functions are added to the standard TIG
features.
4.- Easy TIG mode
You only need to adjust the work intensity to start operating. The
machine will set by itself all parameters assuming that a carbon
steel is welded when it is in the direct current 'DC' mode (button
16), or aluminium when it is the alternating current 'AC' mode.
Notice. The easy mode only applies to model TIG AC/DC 200 HF.
SETTING OF THE 2T/4T TRIGGER PROCESS
Pushbutton 17 allows choosing among two touch and four touch
modes. Basically, the 2T mode achieves welding when keeping
the trigger pressed, while the 4T mode allows welding without
pulling the trigger, whereby behavior of the intensity slopes is
affected. It is essential to understand and respect the cycles
when wishing to use the machine without problems and without
false failures.
2T MODE
1.- The machine welds when the trigger of the torch is pulled.
2.- The machine does not weld when the trigger of the torch is
not pulled.
Bear in mind that, each time the trigger is pulled again, the
machine starts from zero the welding process you have
configured including gas flow times and slopes. Respect the
configured cycles and wait for the appearance of the arc in due
time.
4T MODE
1.- While the trigger is pulled for the first time, the pre-flux cycle
is executed, the arc is struck, and the starting amperage of the
initial welding slope is maintained.
2.- When the trigger is released for the first time, the slope up
ENGLISH
33
cycle and the programmed welding process are executed.
3.- When pulling the trigger for the second time, the slope down
cycle is executed and the final amperage of the final welding
slope is maintained.
4.- When the trigger is released for the second time, the machine
stops supplying current and executes the gas post-flux cycle.
The same as in connection with the 2T mode, please respect the
cycles as configures and wait for the time periods you may have
programmed the machine with.
PULSED TIG
This process allows for improved control of heat supply of the
arc. The use of this process is recommended for:
1.- Welding small thicknesses.
2.- Welding metals or heat-sensitive finishing.
3.- Welding materials with risk of twisting.
Pulsed TIG consists in transforming the flat and continuous
direct welding current of the standard TIG into a periodic square
current of two levels that is generated by a micro-processed
inverter. The high level (simply called pulse) achieves the actual
weld while the low level (called base) maintains the arc ignited
without overheating the workpiece.
SETTING. The pulse is defined by parameters 8, 9, 10 and 11:
1. Pulse frequency. At low frequency, as for example 1 Hz, an
accurate filling of 1 drop per pulse with a perfect finishing is
achieved. At high frequency, as for example starting at 80 Hz,
improved finishing and improved ratios of bead width and its
penetration are achieved.
2. Electric intensity of the high half-wave of the pulse. Refer
(in this manual) to the table of working intensities and apply,
according to the material, the thickness of the piece, penetration,
finishing and joint type.
3. Electric intensity of the low half-wave of the pulse. It is normally
between 20% and 50% of the intensity of the high half-wave.
4. Duty cycle respect to pulse width. This is the ratio between the
width of the high pulse and the low pulse. Usual ratios are 40%
pulse versus 60% base.
Bear in mind that nominal amperages will be higher in order to
achieve an effective amperage equivalent to standard welding.
In single-pulse-per-drop mode, you must bear in mind that the
4 factors are intimately related. Prior to production welding, test
the advance of the filler rod per each drop, and the excess or
lack of fusion in accordance with the intensities of pulse and
base and the duty cycle thereof. Higher intensities allow a higher
speed in exchange of a greater difficulty in controlling the weld
puddle and a decrease of the life of the tungsten electrode.
SETTING OF THE DIRECTION OF THE WELDING ARC
Select the direction of the electric current of the welding arc
using button 16.
• Select alternating current (AC) for welding aluminium,
magnesium and alloys thereof.
• Select direct current (DC) for steels and the rest of materials.
Alternating current facilitates welding on material having high
surface fusion temperatures while having low fusion temperature
in their insides. A portion of the half-wave is used to strip and
penetrate the material, and the other to effectively fuse the mass
thereof.
SETTING. The alternating (AC) mode is defined by parameters
33