STEALTH DIGI-TIG 320 AC/DC PULSE
10
2.3 Working Principle
The working principle of the DIGI-TIG 320 AC/DC PULSE welding machine is shown as
follows: Three-phase 380V work frequency AC is converted into DC (about 312V), then
is converted to medium frequency AC (about 20Khz) by inverter device (IGBT), after
reducing voltage by medium transformer (the main transformer) and converting by
medium frequency (fast recovery diodes). It is output by DC or AC by IGBT selection.
The circuit adopts current feedback control technology to ensure current output
stability. Meanwhile, the welding current parameter can be adjusted continuously and
steplessly to meet with the requirements of welding craft.
2.4 Volt-Ampere Characteristic
The DIGI-TIG 320 AC/DC PULSE welding machine has an excellent volt-ampere
characteristic, as shown as the following graph. The relation between the conventional
rated loading voltage U
2
and the conventional welding current I
2
is as follows:
When I
2
≤
600A, U
2
=10+0.04I
2
(V); When I
2
>600A,U
2
=34(V).
SUMMARY
8
IGBT——Insulation Gate Bipolar Transistor
TIG——Tungsten Insert Gas welding
§2.2 Module Explanation
The module explanation of arc welding machine must accord with the correlative prescripts of
National Standard GB10249. It is explained as the following (take TIG 320 AC/DC PULSE as an
example).
TIG 320 AC/DC PULSE
PULSE
AC/DC welding machine
Max welding current 320A
TIG welding machine/MMA
§2.3 Working Principle
The working principle of TIG 320 400 AC/DC welding machines is shown as the following figure.
Three-phase 380V work frequency AC is rectified into DC (about 312V), then is converted to medium
frequency AC (about 20KHz) by inverter device (IGBT module), after reducing voltage by medium
transformer (the main transformer) and rectifying by medium frequency rectifier (fast recovery diodes),
then is outputted DC or AC by selecting IGBT module. The circuit adopts current feedback control
technology to insure current output stably. Meanwhile, the welding current parameter can be adjusted
continuously and steplessly to meet with the requirements of welding craft.
Rectify
Inverter
Medium
frequency
transformer
Medium
frequency
rectify
Hall device
Current positive-
feedback control
DC
AC
DC
AC
DC
380V,50HZ
Three-phases AC
SUMMARY
9
§2.4 Volt-Ampere Characteristic
TIG 320 400 AC/DC welding machine has an excellent volt-ampere characteristic, whose graph is
shown as the following figure. The relation between the conventional rated loading voltage U
2
and the
conventional welding current I
2
is as follows:
When I
2
≤600A
,
U
2
=10+0.04I
2
(V); When I
2
>
600A,U
2
=34(V).
67
34
10
0
600
I
2
(
A
)
U
2
(
V
)
Working
point
Volt-ampere characteristic
The relation between the
conventional loading
voltage and welding current