Arcoweld ARCOSTICK MMA 180, Operator'S Manual

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SUMMARY
6
2 Summary
2.1 Brief Introduction
Arcostick welders are general MMA arc welder which adopts the latest pulse width modulation
(PWM) technology and the insulated gate bipolar transistor (IGBT) power module.
Arcostick series welders have excellent performance: constant current output makes welding arc
more stable; fast dynamic response speed reduces the impact from the arc length fluctuation to
the current; accurate stepless current adjustment and pre-setting function. There are also some
automatic protection functions for under voltage, over current, overheat, etc. inside the welders.
Should these problems occur the alarm on the front panel will light up and at the same time the
output current will be cut off. It can self-protect and prolong the using life and greatly improved
the reliability and practicability of the welders.
Arcostick series welders can also realize TIG operation. In MMA operation, if the electrode
touches workpiece over two seconds, the welding current will drop to the minimum current
automatically to protect the electrode. In TIG operation, the minimum current will be outputted
firstly until the arc is ignited by the lifting method, the output current will rise to the preset value,
which can protect the electrode. At the same time, the arc force and hot start will be provided
with MMA operation.
MMA——Manual Metal Arc welding;
PWM——Pulse-Width Modulation;
IGBT——Insulation Gate Bipolar Transistor;
TIG——Tungsten Inert Gas welding.
2.2 Working Principle
The working principle of Arcostick series welders is shown as the following figure. Single phase
220V±10% work frequency (50/60 Hz) AC is rectified into DC, then is converted to medium
frequency AC (about 20KHz) by inverter device (IGBT module), after reducing voltage by medium
transformer (the main transformer) and rectified by medium frequency rectifier (fast recovery
diodes) and is outputted by inductance filtering. The circuit adopts current feedback control