Measuring The Welding Circuit Resistance R; General Remarks - Fronius Trans Pocket 4000 CEL Operating Instructions/Spare Parts List

Measuring the welding circuit resistance r

General remarks

Measuring the welding circuit resistance "r" makes it possible to have a constant wel-
ding result at all times, even with hosepacks of different lengths. The welding voltage at
the arc is then always precisely regulated, regardless of the length and cross-sectional
area of the hosepack.
After it has been measured, the welding circuit resistance is indicated on the right-hand
display.
r ... Welding circuit resistance ... x milliohms (e.g. 11.4 milliohms)
If the welding circuit resistance "r" has been measured correctly, the welding voltage will
correspond exactly to the welding voltage at the arc.
If you manually measure the voltage at the output jacks of the power source, this voltage
will be higher than the welding voltage at the arc - that is, higher by the same amount as
the voltage-drop taking place in the "welding-potential cable".
-
-
To measure the 1.
welding circuit
resistance "r"
2.
3.
4.
NOTE!The welding circuit resistance "r" will depend on the hosepack being
used. This means that the measurement to find out the welding circuit resis-
tance "r" must be:
repeated if there is any change in the length or cross-sectional area of the hose-
pack;
carried out separately for each separate welding process (with the respective
welding lines)
Make an earth connection to the workpiece
NOTE! Make sure that the contact between the earthing clamp and the workpi-
ece is on a cleaned section of the workpiece.
Plug in the machine to the mains
Shift the mains switch (8) to the - I - position
Select function "r" in the second menu level (2nd)
NOTE! Make sure that the contact between the rod electrode (i.e. the tungsten
electrode) and the workpiece is on a cleaned section of the workpiece.
5. Clamp the electrode holder or chuck
for the tungsten electrode firmly to the
workpiece, resp. press firmly against
the workpiece.
6. Briefly press the Setup / Store button
(7) The welding circuit resistance is
now calculated; during the measure-
ment, the right-hand display reads
"run"
7. The measurement is finished when
the welding circuit resistance is shown
on the right-hand display (e.g. 11.4
milliohms)
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