Controller build for Plasma

It's snug. 2 x thcad-5s stacked. 24V supply on the inside of the door. Time to start wiring it up.

Have you considered using the SSR's on the 7i96 board? I ask because I see it's neat but packed, and you have what looks like a 4 relay board there.

Yes I plan on using the ssr's. If I run out of room and need more terminal blocks I will ditch the relays

I personally would ditch the relays now becasue you are currently adding one more failure point that does not need to be there.

This is a Mesa card you are using not some emasculated BOB in Windows.

rodw wrote:

xnaron wrote: @RodW I know we had talked about the 25K 5Watt resistor needed for the ohmic thcad-5 setup. Does it replace the 300K resistor below?

No Its in addition to it on the high voltage side as a pull down or pullup. I'll check it out when I get a chance and advise.

Thanks. My eyes read the diagram wrong on the plasma primer. It is 390K not 300K

I am wiring up my controller this weekend.

I am using a THCAD-5 for my Torch Voltage. I would like to keep the Powermax 65 set to 50:1

Do you know what my THCAD divider setting should be?

xnaron wrote: @RodW I know we had talked about the 25K 5Watt resistor needed for the ohmic thcad-5 setup. Does it replace the 300K resistor below?

I updated the diagram to include the 24K 5W resister Rod, myself, and a few others have added to make the deal less sensitive to water tables:



You should also use Rod's Ohmic3.comp which I've attached as well (remove the .txt from the file name). To use it you'll have to use Halcompile and install it. Also, you Have to point your <machine>_connections.hal file to it (change ohmic in Rod's Spaceship example to ohmic3). Not certain how familiar you are or what you are running, but if you are using a buildbot version of LinuxCNC, you'll have to install the dev stuffs first:

Then to install ohmic3.comp (Note that you have to point the terminal to the directory where ohmic3.comp is located before running the command).
Also, it's worth noting that the example on the plasma primer Rod discusses hooking the thcad up to the IDX encoder. You can use Encoder B if you'd like. I think Rod blew his out accidentally :lol: Also, make sure you are up to date with the latest version of PlasmaC.

xnaron wrote: Do you know what my THCAD divider setting should be?

F/32 is what is recommended, unless you are using a parallel port (which I dont think you are).

Excellent! Thank you @snowgoer540.

So 1/32 for the ohmic thcad-5 setting. Is it the same for the THCAD-5 that is connected to the 50:1 on the hypertherm?

xnaron wrote: Excellent! Thank you @snowgoer540.

So 1/32 for the ohmic thcad-5 setting. Is it the same for the THCAD-5 that is connected to the 50:1 on the hypertherm?

You're welcome.

Yep, they're both the same!