[nikolaii]

Hey guys my name is Nick this is my first post here. I've built a CNC plasma table and the only thing holding me back is the ARC OK signal in mach 3.

I have a thermal dynamics cut-master 42 and I have modified it to output the torch switch and the on board ARC OK signal. I did not want to spend the money for a THC control.

The problem Im having is that the input on the breakout board im using is looking for a switch. The ARC OK signal coming from my machine is not a relay like switch, the signal is actually changing voltage from -.7v to +5v instead. How do I use a signal like that for an input?

The only thing I can think of to use is like a transistor or solid state relay and use that signal to control it and trick the break out board to think its a switch. But im not electrically savvy I know there's some way to do it without all that.

This is the breakout board im using I am trying to use one of the limit switch inputs as the ARC OK signal imput

[mcv]

The ARC OK signal coming from my machine is not a relay like switch, the signal is actually changing voltage from -.7v to +5v instead. How do I use a signal like that for an input?

use the output voltage to power a 5v relay ....google 5V relay
then use 2 legs of relay output to the BOB

[asuratman]

Can we use 70 v power supply on that BOB?

[nikolaii]

Thanks for the reply but after being impatient and coming to realize how important a THC is and putting all this time and effort in my machine I bit the bullet and just ordered the Proma - Electronica THC 150 from poland through ebay. Ill get it hooked up when it gets here and take some pics of my machine running if you guys are intrested! Ill put one up as it is now.

Attachment 336672

[nikolaii]

Yeah I wanted to try the relay but I just dont know how the signal would would react. I didnt want to fry any of the electronics on my plasma cutter trying to drive a relay and I wasn't sure exactly how much amperage I could get out of the Arc OK circuit without effecting it somehow. It doesnt take much to run a relay but Its just all in the unknown for me. I only got by wiring this by tutorials hah