This thread has some interesting reading. I have never cut using a mechanized plasma. I have two questions (maybe it will jog or bring forth some obscure, faint idea?), What is the actual range of "ohmic value"? Can this be added to or subtracted effectively by a user/manual pot? Second, why do we want to slow down in a corner? It may seem ignorant, but it is an approach from the other direction. Again, I don't have a clue what I am talking about. I can hear a Victor 3 hose torch (in particular, although we use 2 hose Victor and Harris torches as well) make a faster rip and blow sound at speed in a corner and mellow out in a straight away, which means we use a corner to set our max speed. If we use a straight away as our set point, then the corner will usually sever/bevel inward at the apex.
From Torchhead:
"From doing support on plasma cutting for years, I do know that the more information you have, the easier it is to find and fix a problem. Since cut current is "assumed" to be what the dial is set to, things like bad workclamp connections or something wrong in the power section is difficult to diagnose."
We assume we are setting a voltage (or amperage or travel speed, etc.) based on a gauge, meter or scale on a dial and that is usually on the machine or power source. Actual tip voltage could be very different even from shielding or lack of, much less grounding and other tangible hurdles. The info on one end could be literally a hundred feet away from the source.
One of our weld heads has a Laurel (or laurate or something like that) amp meter that has a "response time" setting. When we set it to it's lowest or quickest read time we can actually "see" the grind marks left by a 50 grit grind wheel in amperage "up and downs". To keep an operator from going nuts we set it at .5 second reads. There it will only tell you if your weld surface is level (generally a 1 inch wide weld and the oscillation will vary the amps by 10 amps or so if not level). I could not imagine the algorithm that would have to go into the detail on this thread.
Happy Monday!
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