REHM TIGER 180 AC/DC ULTRA, Руководство по эксплуатации

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Function description
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4.6.14 AC balance ( )
The setting of AC balance [4] is performed as described in Section 4.6.1. The AC
balance setting option is only available with AC current welding with TIG. It
ranges from -5 to +5 and enables the arc to be influenced as well as the
penetration and cleaning when welding aluminium over a very large range. In the
centre position (0) the negative and positive welding current is equally distributed
over time. With an increasing negative value the share of the negative welding
current increases (up to -5) and the positive share reduces. This makes the arc
more narrow and generates a deeper weld penetration at the same time as a low
electrode load. With an increasing positive value the share of the positive welding
current increases (up to +5) and the negative share reduces. The cleaning of the
weld pool is improved by the positive share. The arc is wider and heat
penetration less deep. The use of the highest possible negative value whilst
maintaining a sufficient cleaning effect is recommended.
4.6.15 AC frequency (Hz)
The setting of the frequency Hz [4] is performed as described in Section 4.6.1.
The frequency setting option is only available with AC current welding with TIG.
The frequency value determines how fast the output polarity reversal takes place
one after the other. The setting range extends from 30 Hz to 300 Hz. For
example, at a frequency of 200 Hz the polarity reversal at the output socket from
plus to minus and back occurs every 5ms (=0.005 seconds). The welding current
drops to zero with every polarity reversal, ignites again in the opposite direction
and increases to the set welding current. The sinus form used in this processor
controlled process results in a significant noise reduction and technical welding
benefits when AC welding.
The REHM patented automatic frequency control can be selected as a special
feature for TIG AC current welding. To activate, the setting for the frequency is
switched to "On", which switches on under 30 Hz.
The automatic frequency control developed by REHM combines the benefits of
a very stable arc in the lower welding current range with the benefits of a high
electrode capacity in the high current range. The AC frequency is automatically
adjusted to the actual momentary value of the welding current.
Normally, the selection of automatic frequency control makes setting the
frequency superfluous. This setting option provides unlimited flexibility other than
a few special application-specific cases where it is desirable to use a frequency
that is different to that selected by the automatic frequency control.
4.6.16 Digital display
The 3-digit display [5] provides a quick and clear display of the welding
parameters, all relevant information and also error messages (see Section 7).
The LEDs [12] to the right of the digital display indicate the selected units by
illuminating.