15 | P a g e
PATON
®
PSI STANDARD SERIES DC MIG/MAG TIG/MMA
3.8. REDUCTION OF OPEN – CIRUCUIT VOLTAGE
When welding works with the manual arc welding process are being performed on vessels, tanks, or other
objects with higher requirements for electrical safety, it is reasonable to use the reduction of open-circuit
voltage function
[VOLT REDUCTION DEVICE]
.
When this function is activated, the output voltage of the welding unit is reduced to the safe value of
12 V
within 0.1 s after the detachment of the electrode from the workpiece.
The welding unit model is equipped with this function, it requires an open-circuit voltage reduce unit
[VOLT REDUCTION DEVICE]
but, by default, this function is deactivated (OFF), as the reduction of open-
circuit voltage impairs arc starting
The procedure for changing the values of the operational parameters of the welding unit for the current welding
process is described in Section 6.1.
3.9. WELDING AT PULSE WELDING CURRENT
This function is designed to simplify the control of a welding process in various spatial welding positions.
This function is also used in welding nonferrous metals. When this function is activated, the application
of pulse welding current improves the mixing of molten metals in the weld area and causes forced action
on the transfer of molten metal drops into the welding pool, therefore the stability of the weld formation
and the stability of the welding process are improved. The pulse welding current in the manual arc
welding process affects the weld parameters similar to the movement of the operator hand in manual arc
welding process, specifically at hard-to-reach places. The proper adjustment of the welding process
parameters in the welding at pulse welding current has a direct effect on the weld quality, specifically
reduces weld metal porosity and decreases the graininess of the weld metal. As a result of the improved
weld quality, the weld strength increases.
To activate this function, it is necessary to set the following three operational parameters of the welding
process: current pulse amplitude
[POWER OF PULSE]
,
current pulse frequency
[FREQUENCY OF PULSE]
,
and duty cycle
[DUTY CYCLE OF PULSE].
By default, the current pulse amplitude is 0
[OFF],
that is, the
function is switched off, the current pulse frequency is 50 Hz, and the duty cycle is 50 %. To activate the
function, set the current pulse amplitude
[POWER OF PULSE]
higher than 0. The current pulse amplitude
should be set in percentage of the welding current specified for the welding process.
Example
:
Welding is to be performed with electrode wire 3.0 mm in diameter. The set welding
current is 90 A. The current pulse amplitude is 40 %. The current pulse frequency is 50 Hz
(default value). The duty cycle is 50 % (default value).
Result:
The result is the following: the welding current pulse amplitude will be in the range of
54 … 126 A, the current pulse frequency will be 50 Hz, and the current pulse length will
be equal to the length of an interval between pulses. If the duty cycle is
not
equal to 50 %,
the current pulses will be
nonsymmetrical relative to the intervals between pulses, but the
average welding current value will be equal to the set welding current value of 90 A. As a
result, the average heat input to the weld will not change.
Default
"duty cycle"
= 50%
"duty cycle"
= 20%
"duty cycle"
= 70%
t, s
t, s
t, s
Summary of Contents for PSI 160 Standard
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