Hypertherm THC

[Dherman]

Hello. I have had my plasma for a long time and haven’t used it in forever because it was made poorly. Recently I did a ton of upgrade and it was well work the work.

The last part to figure out is the THC. I have a Proma and it’s connected to my gecko drive. The question I have is I don’t have a port for cnc on the back of my machine so it’s not a standard hookup. I watched a video where a guy opened up his machine and hooked it up to the lugs in the photo. Is this right? He connected the wires to the outside wire on the proma.. I would think those port are for the 50:1.

Lastly I made a floating head and I don’t know where to connect those wires to….

Not sure if it matters for I have a Hypertherm 65.

Any help is appreciated

Dan

[djreiswig]

For the THC, connect to the wires they go to the torch & work lead. This will give you raw arc volts. The work lead is +. I'm not sure what those terminals are for.
What do you mean by wires from a floating head? Do you mean the switch that detects when the torch probes to find the material? I don't think that is part of your THC circuit. It would most likely connect to an input on your machine control. You don't mention what that is. Need some more details.

[Dherman]

Thanks for the reply. I have a Lightning CNC. They were in business for a short time and screwed over a lot of people. I have a Hypertherm 65, a Grecko g540 as the driver and proma 150.

As for the floating head I’m talking about the limit switch… doesn’t that tell the THC it has touched off? I made the floating head myself recently so it’s never been connected to anything.

If you buy an aftermarket CPC and install it onto the plasma it has to hook up somewhere. Instead of tapping into the plug I’m trying to find out where that is wired to. If I cannot find that I go to raw voltage and forgot the 50:1?

I apologize for any ignorance. I’m a machinist/welder so this stuff it way above me.. that’s why it’s been sitting collecting dust for years.

Dan

[weldguy]

Hey Dan

Without a CPC port you will need to use a raw voltage signal and the connections for that can be found in this topic viewtopic.php?p=213727#p213727

I have never wired up a Proma but after a quick look its appears as though your IHS switch is wired to the "Mat Det" plug circled below.

IHS.PNG (124.98 KiB) Viewed 264 times

[acourtjester]

To help you understand, at the start of a cut routine the torch will move down to touch the top of the metal. This is done with either a floating head switch or a Ohmic sensor. A Ohmic sensor is better as is does not make the metal defect ( in thin metal) as it works almost intently, the floating head will also have a backlash (switch offset from on/off ) which needs to be in the G-code to correctly have the pierce height. The floating head switch can also be used as a backup or safety for the Ohmic sensor (dirty metal/rust on surface). The Arc Ok signal signals the controller that the plasma stream has started, either from the plasma unit or Proma, it will start the cutting after the delay for the pierce to complete. The THC only comes into effect after the torch start moving to cut, another slight delay in the THC for arc stabilization from pierce to cut height. The Proma ( or other THC) will then send up/down commands to the controller to keep the cut height constant.

[acourtjester]

Here is a video on how to setup the THC and fine tune the Arc voltage for the correct cut height, not a Proma but all works the same to check torch height.