EtherCAT plasma torch voltage reader

I just uploaded the description and design of the EaserCAT 7000 board and the two plasma torch voltage readers THTIC and THTIC2 on github.
github.com/MetalMusings/MyOwnEtherCATDev...ith-thtic-and-thtic2

Reads the plasma voltage, feeds it to my EaserCAT-7000 card over I2C and makes it available either as raw data read from the ADC or scaled to calibrated plasma torch voltage.
I have used it for maybe an hour of cutting (feed time) and it just works. Very happy with it.
There are two versions, for a bit blurry reasons, but always good with options I guess.
The ADC card is small 55x32 mm.
 
 
 

Very cool! If you wanted another plasma challenge, how about an ethercat plasma board powered by 24v PoE so you can mount a board that does the ArcOK input, Torch on relay and the torch voltage right at the plasma cutter itself. Add a PoE injector in your control panel amd its all self contained.

It can be done pretty easily with external components.
Feed 24V using the unused leads in the CAT cable, and a step-down unit from 24V to 5V and there you have it.
At the prototype stage this simple cable will work. And  24V stepdown converter (board needs 5V) is dirt cheap.
 
 

BTW the photo-diode opens so good that I don't need a torch-on relay, but can be had if needed.

Perfect! Not sure what plasma cutter you have but if it was say hypertherm, a surface mount circular connector that just pushes into the socket on the machine and you would have a nice complete self mounting package. I used the 7i76e spindle relay for torch on so there is nothing wrong with your photo diode. You just need to add a pull down resistor on the arcOK as discussed in the qtplasmac docs. 

Of course if you had a XPR hi def its Ethercat anyway!

The idea to power it from 24V stuck, I am going to do it that way. Will get rid of a 5V power supply in the cabinet.

The voltage reader can fit in a connector, that would be possible, but not the EtherCAT components. They need say 100x60 mm as it is today.
Two-sided and dense packing, no still not inside a connector.
I will try that idea to put the EtherCAT function on the plasma cutter. It doesn't make sense for me since it is a matter of 0.5 meter, but why not?
Could be a question of how long the ethernet cable can safely be versus how long the I2C cable can be.
That power injector/ejector is here on Monday.

I have a Herocut 55i, it is all very small scale, hobby and prototypes for my enjoyment.
I get voltage, arc-ok and can control torch-on. Power level, air pressure isn't, well require more work than I want to spend right now.

Must also say I am very happy with QtPlasmaC, works really nice.

I wasn't thinking of putting it the connector shell but having a surface mount connector if they exist that plugs straight in like a raspberry pi hat.
The amphenol connector used by Hypertherm and Thermal Dynamics, I think comes with surface mount options....

Glad you like my idea, Pretty cool one I thought!

I see, a bit like EasyCAT kind but for the voltage reader.
 

I am more into putting the torch voltage reader components onto the EaserCAT board.
Now when I have looked at it I am not so worried about the voltage levels and that.
One just need to take some precautions.
And if I understand right, most new plasma cutters gives out scaled down voltage
so it is more to handle the floating voltage, and this circuitry does that.