2.5
Working
Principle
GRAND MIG has an excellent volt-ampere characteristic, whose graph is shown as the following figure.
The relation between the rated loading voltage U2 and welding current I2 is as follows: U2=14+0.05I2(V)
2.6
Volt-Ampere
Characteristic
The working principle of GRAND MIG is shown as the following figure. Three-phase 380V work
frequency AC is rectified into DC
（
530V
）
, then is converted to medium frequency AC (about 20KHz)
by inverter device (IGBT), after reducing voltage by medium transformer (the main transformer) and
rectifying by medium frequency rectifier (fast recovery diodes), and is outputted by inductance
filtering. The circuit adopts current feedback control technology to insure current output stably when
MMA or TIG. And adopts voltage feedback control technology to insure voltage output stably when
MIG. Meanwhile, the welding current parameter can be adjusted continuously and infinitely to meet
with the requirements of welding craft.
OVERVIEW
44
14
0
600
I
o
（
A
）
U
o
（
V
）
Working point
Volt-ampere characteristic
The relation between the rated loading
voltage and welding current
Summary of Contents for GRAND MIG 351 MULTI SYN
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