js55
The arc control on the XMT actually controls both inductance and arc force (dig). When the machine is set in the CV mode, this will control the inductance. As inductance is increased the resistance to change in current increases. This in effect will limit the number of shorts a machine can have in a given time period. Because the shorts are now limited, the amount of time the machines spends in the voltage phase increases or an increase in "arc on time" is seen. This gives an arc that looks more fluttery, and is why poor wetting materials such as stainless are ran on high inductance, it give an arc that holds the voltage on longer, helping wet out the puddle. However, too much inductance will cause your welding starts to deteriorate. Short circuit current will not be supplied fast enough and the wire will hammer the plate.
When the machine is set to CC mode such as for stick welding, then the arc force knob controls dig. As this knob is increased the available short circuit current increases. For instance when you are preset at 125 amps and dig is at 0% your short circuit current will may only reach 135 amps. When that dig is increased short circuit current will reach much higher maybe 300 amps. How high the current will reach can be determined by looking at a volt/amp curve for that particular machine.
Kix,
Burn back is the amount of power supplied for a given time after releasing the welding gun trigger. This is done to keep the end of the wire from sticking in the weld puddle at the end of the bead. To much burn back and the wire will burn back to the contact tip, not enough and it will stick in the puddle. Kix, I have heard of you out side of this forum, we have mutual aquaitances. I doubt that I live too far from you. Get hold of me offline and we should talk.