14 kVA Kohler Three Phase Multi Process DC Arc Welder Generator_Manual

03/06/19 M33 (EVO MULTI 4)_EN
ENGLISH
ENGLISH
M
33.2
WELDING DIGITAL CONTROL
EVO MULTI4 CONTROL
REV.0-06/19
It is possible to see in gure 2.6that in PULSED TIG it is possi-
ble to reduce the welding cur-rent for a short time. This is used
to reduce the heating of the working piece. Parameters that
can be regulated are: CURRENT with the LEFT ENCODER
and FREQUENCY with the RIGHT ENCODER.
Figure 2.2: Behavior of the current in normal TIG and pulsed
Figure 2.3: Different behaviors of the current changing the switching
frequency
The current that is set with the left encoder is the maximum
current of the waveform, the frequency is correlated with the
time that is between the reduced current, higher the frequency
lower the time windows. In gure 2.3 it is possible to see two
different frequency waveforms, the allowed range is between
0.5Hz and 10Hz.
Secondary parameters
Secondary parameters of the TIG welding are:
- DUTY CYCLE
- DELTA CURRENT
- TIME of turn off ramp
- CURRENT at the end of the turn off ramp
- TIME preow
- TIME postow
DUTY CYCLE
Duty cycle is the percentage of the time in which the current is
higher than the low level.
Figure 2.4: Current at different duty cycles
In gure 2.4 it is possible to see that duty cycle does not chan-
ge the maximum or the minimum current, only the average
current.
DELTA CURRENT
The delta current indicates how deep is the low level of the
current, higher the delta lower the current when the arc is tur-
ned off. The parameter can be set between 0% and 50%. A
value equal to 0 removes the pulsed capability from TIG.
Time of turn off ramp
This parameter tells how much time it takes to decrese the
current when the toch switch is not pressed anymore. It can be
set between 3 and 8 seconds.
Current at the end of the ramp
Before turning of completely the current, for 2 seconds it is
kept a base current, this value can be set between 20A and
100A.
TEMPO preow
If the machine has a gas valve, this parameter sets how much
time the gas is open before starting the welding, it is possible
to set this time between 0 and 20 seconds.
TEMPO postow
If the machine has a gas valve, this parameter sets how much
time the gas is open after nishing the welding, it is possible to
set this time between 0 and 20 seconds.
Figure 2.5: Current changing the delta current
TIG LIFT ARC PULSE
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