Arcoweld ArcoMiG LCD 250C, Руководство оператора

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SUMMARY
11
MMA——Manual Metal Arc welding
PWM——Pulse-Width Modulation
IGBT——Insulation Gate Bipolar Transistor
2.2 Module Explanation
Arco - Arcomig
Mig – Metal Inert Gas
250C – Max amperage compact machine
2.3 Working Principle
The working principle of the ArcoMig 250c is shown as the following figure. Single phases work
frequency AC 220V (50 Hz) is rectified into DC (about 380V), then is converted to medium frequency AC
(about 44KHz) by inverter device (IGBT), after reducing voltage by medium transformer (the main
transformer) and rectifying by medium frequency rectifier (fast recovery diode), and is outputted by
inductance filtering. 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
220V,50HZ
Single-phases AC
2.4 Volt-Ampere Characteristic
ArcoMig 250C 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, U2=34(V).