Strata EZITIG 205DC, Руководство по эксплуатации

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The relation between the duty cycle “X” and the output welding current “I” is shown as the
right figure.
If the welding machine is overheating, the
IGBT over-heat protection sensing will send a
signal to the welding machine control unit to
cut the output welding current OFF and light
the over-heat pilot lamp on the front panel. In
that case, the machine should not be welding
for 10-15 minutes to cool down with the
fanrunning. When operating the machine again,
the welding output current or the duty cycle
should be reduced.
2.5 Working Principle
The working principle of TIG series of welding machines is shown in the following figure.
Single-phase 220V line frequency AC is rectified into DC (about 315V), then is converted to
medium frequency AC (about 40KHz) by inverter device (IGBT), after reducing voltage by
medium transformer (the main transformer) and rectified by medium frequency rectifier (fast
recovery diode), and is outputted by inductance filtering. The circuit adopts current feedback
control technology to ensure current output stability. Meanwhile, the welding current
parameters can be adjusted continuously and steplessly to meet with the requirements of welding
craft.
2.6 Volt-Ampere Characteristic
TIG series of welding machines has excellent volt-ampere characteristic. Referring to the
following graph. In TIG welding, the relation between the rated loading voltage U
2
and welding
Rectify Inverter
Medium
frequency
transformer
Medium
frequency
rectify
Hall device
Current positive-
feedback control
Three-phase, AC
DC
AC DC
380V
，
50Hz
AC DC
Single-phase, AC
220V, 50HZ
Relation of welding current and
duty cycle for
EZITIG205DC
10
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EZITIG 205DC