How to find Raw Voltage

I am stuck at getting the correct Raw Voltage from the Plasma torch.

Manual torch fire works fine.
I can do a “straight cut” without THC enabled fine.

I have a couple plasma torches that I would like to be able to hookup and was wondering if there was a general procedure to locate the wires that would produce the DC voltage necessary for the VIM input?

On the plasma board there is a “OUT +” which goes to the ground and and “OUT -” which goes to the torch, but when I put a MM on them and pull trigger…no voltage.

My dad has a older P-Tron 75 and my brother has a newer CUT50L (low frequency, not like the HF Cut50) that I have been doing the current testing on.

In order to see raw voltage on mine, I had to have air supplied to my plasma cutter. There is a pneumatic safety switch on mine that won’t enable the voltage if there is no air supplied to the unit.

After realizing I forgot to probe the last combination of wires, I got the correct voltage reading from the pilot arc post and the torch.

Hi there stlmech, I´m having the same problems with a plasma cut 60l. i cant get a correct voltage raw… could you please help on this? i do really appreciate this. here is attache some pictures of my plasma.

You should probably try and ask someone else my friend. I had a Cut 50L and if my memory serves, I was not testing thing on the outside of the machine. My plasma is kind of buried at the moment, but I know the wiring harness I made comes out from the inside.

That is a high frequency plasma cutter and you can not get raw voltage from it for a plasma table. It won’t work right anyway, you need to get a new plasma cutter that is not HF.


Actually is Low frecuency and at the moment works just perfect with floating z head on my cnc machine. i bought a THC control and i´m looking to get the raw voltage to connect it.

Thank you for your response. that would be great to know about the wiring harness, actually the cut 50l its the same as 60L.

Interesting. This looks like a port for the High Frequency pilot arc. If this were a blowback start machine I don’t think you would need this port. Take a pic of your consumables

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Hi there my friend, this is a sungoldpower CUT60L low frecuency. plasma the torch is p80. It works just perfect with floating z head on my cnc. I have tested with usb bob, ethernet and parallel port. Works just perfect so i assume that is Low frecuency… manual says so.
The plasma has been working for a year almost without any issue.

I’m not saying you are wrong. And I’m not going to argue with success. It just looks an awful lot like some HF machines I have had in the past. I tried looking it up. Couldn’t find one to look at it.

Happy cutting :+1:t2:


Oh noo mate! Im not arguing!! just i wanted to tell that plasma is low frecuency, in fact is next to my laptop… i know its a really cheap plasma but its have been working great. i suppose that is low frecuency cause i didnt have any interference with stepper motor and bob… its strange that i got dc voltage but its to low for the thc. When torch pierce voltage goes to around 100v then goes down to 55-60volts when cutting


Give me a couple days and I will see if I can open up mine and take some pics for you.

A P80 torch is a High Frequency torch, Therefore the plasma cutter is a HF plasma cutter. Also the 2 left terminals are both positive so I can not see were your getting voltage across them.


That plasma cutter is featured in this video with a different torch.

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Interesting. The cutter featured in the video uses a IPT 40 torch not the P80. Difference between the 60L and 50L?

Man that electrode was shot! I’m surprised it kept cutting as long as it did after the green flame first showed up. I was cringing waiting for the fireworks! He gets pretty close to the solution to his consumable life issues but doesn’t quite get there in this video. Another YouTuber who didn’t have the benefit of learning from you all here on the forum.


Edit I did even notice the 60L 50L difference.

If the torch is timed correctly it can be used on a HF plasma cutter. I have a 45 amp HF plasma cutter with a S45 style torch on it here. It came to me as a demo to be tested.