THC config that works.

It is absolutely necesary to use shielded cables in your case, you can use even RG 58 or RG59 tv antena or video camera or audio cable with one wire in the midle and one as a shield. Just connect the shield to the ground on your bob and the midle wire to the input.

I also forgot to mention one of the common errors i have seen around : stop grounding everything at the same point. That is o.k. for other machines, but it can be fatal on plasma cutters. I have explained that in this forum and some others so i won't repeat myself, just to prove a point : almost all power supplyes have ground connected to minus terminal internaly as it is supoesed to be but the plasma cutter clamp that is usualy clamped to the material or the ribs on the cnc is the positive.
Tom

Do a test an wrap the limit switch with alu foil properly, afetr you change the wire. If the switch is close to the torch that will help a lot.

Thanks, will do it in the morning.

Regards
Jacob

Another thing that can help is debouncing the input signals with the hal debounce component

Hi, so I did not wrap the wire in Al foil, but I did add a shielded cable, not sure whether it helped, may have installed it wrong. What I did do is debounce the float switch electrically with a 100nF across the switch, I went one step further however and installed and opto-coupler. I also rewired the switch to be normally open.

There is a new problem however. For some reason now, as soon as the arc establishes, and motion begins, the machine moves extremely slow and I have no idea why. Everything works fine, even my own implementation of THC, and normal motion is at the correct speed, but when I issue the M3 command, the motion is extremely slow.

Attached is my thc_toma.ini file

Any ideas???

Regards
Jacob

groblerjf@gmail.com wrote: There is a new problem however. For some reason now, as soon as the arc establishes, and motion begins, the machine moves extremely slow and I have no idea why. Everything works fine, even my own implementation of THC, and normal motion is at the correct speed, but when I issue the M3 command, the motion is extremely slow.

It is slightly hard to work out what is happening without the HAL file, but I notice that you enable adaptive feed in the INI, so my assumption would be that you need to calibrate the input to the adaptive feed pin.