Fronius TransTig 1600, Operating Instructions And Spare Parts List

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22
Fig. 22 TR 50 mc remote control pulsing unit
TR 50mc remote
control pulsing
unit
Remote control units are intended for use in situations where the welding parameters
must be set directly from the welding workplace. The remote control unit is connected
electrically to the power source by means of special cables 5 or 10 m in length.
The following types of remote control unit are available:
-
Manual electrode and TIG remote control unit ..................... TPmc
- TIG pulsed-arc remote control unit ................................... TR50mc
- TIG spot-welding remote control unit ............................... TR51mc
- TIG Remote-control pedal unit ......................................... TR52mc
Remote control operation
General
Since a pre-set amperage is not always ideal for the entire duration of a welding task,
pulsating welding current is often used. For example, when welding pipes in cramped
conditions, a change in amperage is often necessary. Should temperatures rise too high,
there is a danger that liquid metal will begin to drop from the welding pool. Too low, and
the workpiece material will not melt sufficiently. A relatively low welding current (back-
ground current I
2
) rises via a steep up-slope to a considerably higher value (pulse current
I
1
) and drops again after a pre-set period (Duty-Cycle) to the basic setting (background
current I
2
), a process which repeats itself over and over again.
During the welding process, small sections of the weld zone melt and solidify quickly.
Welding a seam using this method is thus considerably easier to control.
This technique is also used when welding thin sheet metal. Each fusion point overlaps
the next, thus forming a neat and regular seam. When the TIG pulsing technique is used
when welding by hand, the welding rod is applied at each current peak.
(Only possible in the lowest frequency range, i.e. 0,2 - 2 Hz).
Higher pulse frequencies are generally used in automatic welding applications and serve
mainly to stabilize the welding arc.