New Project with Mesa 7I96 and THCAD-05

If the Mesa board is powered by 24V then use a 24V relay.
It might be possible to use a DC-DC step down voltage converter to run a 5V relay, but that might induce to much delay turning ON and OFF.

I have a 48v power supply for the drivers but the Mesa board is being powered by 5v as that’s what the board calls for. Now I been reading where you don’t need a relay for the outputs on the Mesa card? Also on the arc ok on my thermal dynamics CM52 I have cnc interface card and it has port 12 and 14 as the arc ok do I have to wire that to power as well with the ground wire going to the input?

TexasCNC wrote: I have a 48v power supply for the drivers but the Mesa board is being powered by 5v as that’s what the board calls for. Now I been reading where you don’t need a relay for the outputs on the Mesa card? Also on the arc ok on my thermal dynamics CM52 I have cnc interface card and it has port 12 and 14 as the arc ok do I have to wire that to power as well with the ground wire going to the input?

That board uses 5v for logic power and up to 36 vdc for I/O. If your using 5vdc for plasma your just asking for trouble. Not sure a good idea to connect output directly to plasma cutter. If you dont understand both sides you could damage one or the other and possibly both. Jus fire a relay and give dry contact to plasma.... way easier and you isolate the two somewhat.

I was going to follow this schematic that another member here used not sure if this will work or if this was his final wiring.

Unless you know and have the exact same plasma cutter as the person who did that wiring diagram, you cannot hook up to you plasma that way. You have to match the voltage of your plasma cutter. And then I wouldnt do it. It clearly says connect a dry contact and they put voltage, "15vdc open circuit voltage at start terminals. REQUIRES DRY CONTACT CLOSURE TO ACTIVATE"

Do what you want but a simple safeguard is to put a 20.00 relay. And that drawing is using 24vdc for I/O.

Its a bit difficult to call but

1. "DRY CONTACT" to me means no voltage is applied
(and the 7I96 outputs apply no voltage, they are just switches)

2. Using the 7I96 output without a relay means it will be faster
and a relay may have a contact wetting issue with the quite small
15V @ a couple mA switched current.

Here is my pin out for my plasma how would hook up my arc ok cables to my card? It shows 30v on pin 12 and 14 and 12v for torch on and off.

Any idea what I need to do here to hookup the arc ok do I need a power supply for it?

TexasCNC wrote: Any idea what I need to do here to hookup the arc ok do I need a power supply for it?

Arc ok looks like it is 12 and 14. It is a dry contact and that should be an input to the mesa board. Do it just like in the drawing.

So I should be fine plugging one end to +24v and the to input pin?