STAYER WELDING TIG AC/DC 190HF PULSED Manual De Instrucciones página 22

2.- When the trigger is released for the first time, the slope up
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.
ENGLISH
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SETTING. The alternating (AC) mode is defined by parameters
12, 13 and 14:
1. Duty cycle with respect to pulse polarity (clean width) to obtain
greater cleanliness in exchange for smaller penetration and vice
versa. You may modify the width within a time range of -40% to
+ 40%.
2. Wave balance with respect to polarity change. It allows moving
the polarity volume from -20% to +20% depending on the needs
of the stability of the welding arc cone (opening it or closing it), of
the advancing speed and cleanliness.
3. Alternating welding current frequency. 20 Hz to 100 Hz. Use
low frequency to achieve wider beads, and in reconstruction
operations. Use high frequency to penetrate into narrower beads.
In turn, the alternating mode (AC) mode may be pulsed to provide
special features, such as facilitating drop-per-drop filling, caloric
control or improved surface finishing. This mode produces pure
square wave without any passing time and excellent cleanliness.
DIAGNOSIS TIG AC/AC:
Error code in TIG AC/DC
804 Thermal Protection
805 Broken torch, switch short
806 Water loss
WELDING FUNCTIONS BY POINTS, REPETITIONS AND RO-
BOTICS
Selecting the SPOT function on button E gives access to the
configuration of spot welding parameters defined by the dura-
tion of each cycle (from 0.1sg to 99.9s), the peak current (5 to
190A), the base current (5 to 190A) the pulse width in relation
to the peak (from 1% to 99%) and the pulse frequency (from 0.2
to 500Hz).
In 4T repeat functions after passing the T1 and T2 times in the
initial cycle, a repetition of the T3 (down ramp) and T4 (up and
weld ramp) times is established each time the trigger is pressed.
In 2T repeat functions, it starts directly in phase T3 / T4. To exit
the repetition cycles, raise the torch to suppress the arc.
For automation / robotics functions, keep in mind that the trigger
input can be operated from any system that considers it a nor-
mally open switch. Use of relay or optoisolator is recommended.
For questions, contact your dealer.
Functions with coated electrode
With the VRD (voltage reduction device) function, the electrode
welding vacuum voltage is reduced to improve the safety that
may be needed in special environments or situations. The price
to pay is a slight worsening of the initial priming of the bow, so if
it is not required it is recommended not to have it activated.
To optimize welding quality you can play with others two
parameters that allow changing the character of the arc and the
heat input They are the frequency, nº17, of the pulse in cycles
per every second (Hz) and the percentage distribution between
the current peak and base,
Finally, two response parameters can be adjusted arc dynamics
in electrode coated mode. They are the strength of arc, arc
force, nº26 so that it will be increased for electrodes cellulosic
or aluminum type and will decrease for electrodes softer
response such as rutile. With the family of basic electrodes
it is recommended to start testing in fit intermediate. The
last parameter, start pulse, or Hot Start, No. 27 ARC START,
establishes a brief increment of power just by priming the
electrode and allows the electrode to start without getting stuck
before entering the normal regime foundry.
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