Lincoln Electric POWER FEED 25M NNS Operator's Manual page 26

POWER FEED™ 25M NNS
WAVE CONTROL
Process Wave Control
Name
Peak Current
GMAW-STT
(Surface Tension
Transfer
Background
Current
Tail-out
No wave
GTAW (TIG)
controls
available.
Effect / Range
Description
Peak Current acts similar to an arc pinch control. Peak Current sets the arc
length and promotes good fusion. Higher peak current levels will cause the arc
to broaden momentarily while increasing arc length. If set too high, globular
transfer may occur. Setting it too low may cause instability and wire stubbing.
Best practice is to adjust for minimum spatter and puddle agitation.
Peak also affects the shape of the root. When using 100% CO2, the peak cur-
Controls arc
rent will be higher than when welding with blended shielded gases. A longer arc
length
length is required with CO2 to reduce spatter.
Background current adjusts the overall heat input into the weld. Changing the
background current changes the shape of the back bead. 100% CO2 requires
less background current than when welding with blended shielding gases.
Regulates bead
contour
Provides addi-
Tail out provides additional power without the molten droplet becoming too
tional power to
large. Increase as necessary to add heat input without increasing arc length.
the arc.
Often this results in faster travel speeds. Note that as tail out increases, the peak
current and/or background current may need to be reduced.
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B 11
OPERATION
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