Snuggly's Plasma Build

If you set for example 5 volt on the common line of the thc, in your case pin 10.
You get out :

pin7 = arc-ok ( +5v when triggered )
pin8 = down ( +5v when triggered )
pin9 = up ( +5v when triggered )

So common works like a relais. Try this yourself.
If you had a parport application, you would be building your next machine dude.



Keep up the good work !!

I'll test the common to pin10.

Yeah I started this build with an arduino and a GRBL shield, then I learned about the HF start torch and that's what started me in on the Mesa board. Plus linuxcnc is really powerful software.

Next build will definitely start out with a healthy amount of lurking and planning.

What the 7I96 input common (TB3 pin 12) connected to?

If you have the Proma common pin connected to the low side of the control power you would expect this kind of wiring:

+24V --> 7I96 input common

7i96input --> Proma Arc-ok

Proma common --> 24V power common

I think Grotius has solved your problem.

Looking at the proma manual its written for a parallel port system which usually switches active low.

The mesa cards are active high.

Now don't do this without confirmation from Tommy or Grotius as I don't want to blow up anything on your hardware but I think your Proma Common terminal should be connected to +24 volt (or what ever voltage you are using for input pins on your 7i96).

So then when the contacts in the Proma close, they will send +24v to your input pins.

Grotius, Tommy, I've never used a Proma. Is it OK to do this?

The 7I96 isolated inputs are either active low or active high so either way will work

PCW wrote: The 7I96 isolated inputs are either active low or active high so either way will work

Ah, the 7i96 manual says

The 7I96 has 11 isolated inputs and 6 isolated outputs. All 11 Isolated inputs have
a common pin. This common pin must be connected to ground for active high inputs and
connected to the I/O power for active low inputs. The 6 isolated outputs are completely
floating switches so can be use for pull-up/pull-down and mixed voltage switching.

So it sounds like there could be a wiring error. The Proma Ground should be attached to TB3 Pin 12 not to his Power supply GND (unless its connected to TB3 Pin 12).