Paton ProMIG-200, User Manual

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PATON ProMIG DC MMA/TIG/MIG/MAG
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of weld defects, which is an extremely negative phenomenon. Therefore, for the set time of
the current ramp-down [t.dn], it is possible to weld the formed cavity. By default, it is set to
OFF
– disabled. See paragraph 6.1 to change the value of any function in the current welding
mode
4.8 PULSE CURRENT WELDING FUNCTION
This function is designed to facilitate the control of the welding process in spatial
positions other than the lower one, as well as when welding non-ferrous metals. The effect
occurs directly on the mixing of the molten metal of the seam, and this, in turn, on the
stability of the seam formation. To some extent, it replaces the movement of the welder's
hand during welding, especially in hard-to-reach places. There is also partially a forced effect
on the transfer of a drop from the filler wire to the weld pool. The correct setting determines
the shape and quality of the seam formation, which reduces the likelihood of pores and
reduces the grain structure, and thus increasing the strength of the welded joint.
To implement this function in the device, you need to set three parameters:
pulsation power [Po.P], pulsation frequency [Fr.P] and pulse/pause ratio (or "duty cycle")
[dut]. By default, pulsation power [Po.P] as a key parameter is set to OFF, i.e., the function
is turned off, and pulsation frequency [Fr.P] and "duty cycle" [dut] at the values of 10.0 Hz
and 50%, respectively. To enable the function, simply set the pulsation power [Po.P] above
zero. This parameter is set as a percentage of the used main welding current set.
Example: welding with a refractory tungsten electrode with a diameter of 2 mm, the
set basic value of the welding current is 100A, and the pulsation power [Po.P] = 30%, while
the pulsation frequency [Fr.P] = 10.0 Hz and "duty cycle" [dut] = 50% by default.
Result: the current will pulse from 70A to 130A at a frequency of 10 Hz; the pulses
will have an equal shape in amplitude and time.
The “duty cycle” parameter is set to 50% by default. Changing this value introduces
an asymmetry between the current pulse time and the current "pause" time:
default
"duty cycle" [dut] = 50%
"duty cycle" [dut] = 20% "duty cycle" [dut] = 70%
The unit will react in such a way that the average current level during the welding
process will be at the level of the set main value of the welding current 100A (as it was set),
respectively, and the heat input to the welding seam will be at the level of the same 100A,
but the stability of the welding process and the mixing of the weld pool will change. This is a
very important condition for the user to accurately estimate the change in the heat input to
the weld pool, e.g., by comparing it with another main current without pulse mode.
t, sec t, sec t, sec