3.3
Connection for MMA welding
Electrode holder and earth clamp
In MMA welding, the welding electrodes must be connected to the correct pole. Normally, the
electrode holder is connected to the positive and the earthing cable to the negative connector.
It is also important to properly adjust the welding current so that the filler material and coating will
melt properly and the welding is efficient. The table below presents the electrode sizes available for
use with the MasterTig LT 250 welding machine and the corresponding welding current values.
MMA Electrodes and corresponding current settings range
Electrode diameter
Fe-Rutile
Fe-Basic
© Kemppi Oy / 1422
1.6 mm
2.0 mm
2.5 mm
30 – 60 A
40 – 80 A
50 – 110 A
30 – 55 A
50 – 80 A
80 – 110 A
3.25 mm
4.0 mm
5.0 mm
80 – 150 A
120 – 210
150 – 250 A
110 – 150 A
140 – 200
200 – 250 A
EN
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