Paton StandardMIG -200, Data Sheet And Operating Manual

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PATON StandardMIG MMA/TIG/MIG/MAG
In order to implement this function, three parameters must be set in the
machine: pulsing power [Po.P], pulsing frequency [Fr.P], and mark‐to‐space ratio
(or duty ratio) [dut]. By default, pulsing power [Po.P], which is the key parameter,
is set to “OFF” position, i.e. disabled, while pulsing frequency [Fr.P] and duty ratio
[dut] are set to the most common values of 20Hz and 50% respectively. In order to
enable this function, it is enough to set pulsing power [Po.P] to a value above zero.
This parameter is set in percent of the voltage set value of the base arc welding.
Example: welding with wire of 0.8mm in diameter, set wire feeding speed is
5.5m/min, set the base value of arc voltage is 18V, and pulsing power [Po.P] = 20%,
while pulsing frequency [Fr.P] = 20Hz and duty ratio [dut] = 50% by default.
Result: current will pulse in the range from 14.4V to 21.6V with a frequency of
20Hz; pulses will be of the same shape in terms of both magnitude and time.
If duty ratio parameter [dut] is changed to a value other than 50%, pulses
become asymmetric—between the current pulse time and the current “pause”
time:
by default
“duty ratio” [dut] = 50% “duty ratio” [dut] = 20% “duty ratio” [dut] = 70%
The machine calculates pulsing in such a way that, at a constant set
differential of pulses, average level of arc voltage is maintained at the level of set
base voltage value of 18V (i.e. equal to the set value), in order to keep the resulting
average heat input into the weld at a constant level of 18V but the stability of the
welding process and the mixing of the weld pool will change
. This is necessary in the
situation, when a user has reduced base current and provided maintenance of stable
welding process using pulses—thus, decrease of heat input can also be clearly
determined by comparison with initial base current.
If the task is to reduce the heat input into the weld using a pulsed mode, for
example, when welding thin metals, it is sufficient to reduce the main source
voltage in a standard way; at the same time, the amplitude of the pulses and
pauses established earlier will automatically adjust to this voltage; respectively, the
user will clearly understand how much he has reduced the current heat input into
the weld compared with the previous mode, while simultaneously changing the
strength and “duty ratio” of the pulses in any combination to obtain the desired
process. This task is not simple, since several parameters are regulated at once.
t, s t, s t, s