REHM INVERTIG.PRO digital 240 DC, 240 AC/DC, Руководство по эксплуатации

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Functional description
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3.7.1.2 AC frequency Hz
The frequency Hz is set as described in Chapter 3.4.2.
The frequency setting can only be made in connection with AC current welding in
the case of TIG. The value for the frequency defines how frequently the output
polarity changes. The adjusting range ranges from 30 Hz to 300 Hz. For
example, at a frequency of 200 Hz the polarity change at the output connection
from plus to minus and back again takes place every 5 ms (=0.005 seconds).
The welding current is reduced to a value of zero whenever a polarity change
takes place, is re-ignited in the opposite direction and increased to the selected
welding current again. The sine wave shape that is used in this process-
controlled procedure leads to a considerable reduction in the amount of noise,
and has technical welding advantages in AC current welding.
REHM recommends setting to the automatic frequency system that has been
patented by REHM . The automatic frequency system automatically adapts the
AC frequency to the current strength. At low welding currents the AC arc is
focussed. This provides reliable root formation, e.g. in fillet welds in thin sheets of
metal. At higher currents the tungsten electrode load is reduced. A long service
life and optimum cost-effectiveness are the result. The automatic frequency
system has particular advantage when working with the
iSystem P1 remote foot
controller.
Fig. 13: INVERTIG.PRO digital / Classic application control panel
Graphical display of frequency