Hey everyone, I’m new to the forum but I’ve had my crossfire pro for over a year now and have run it regularly since the day I got it. I paired it with a razorcut 45 so I could just use the plug and play capabilities. Again no complaints with this machine it’s been great. But I ran into an infamous THC raising during cuts problem recently, and I need a little assistance. So bear with me and hopefully this isn’t too long of a post.

I was running one of my proven production runs on fresh consumables when I noticed the torch start to rise when it was doing internal cuts.

I double checked all of my lines and connections to make sure they’re plugged in and not kinked, didn’t solve the problem.

Then I went into testing the THC system and followed langmuirs trouble shooting guide, and it kept landing me at the moisture in the contacts of the IHS. Which is not the case.

So I decided to start testing voltage testing so I checked for resistance from the USB to the gantry and I got a reading of 3.78 Kohms. The USB port has plenty of clearance and is not touching the control box at all

I removed the control box from the machine to count out the possibility of continuity passing through the control box. I measured again against the USB casing and the gantry and again measured 3.78 kohms.

Then I unplugged everything from the controller except the power cord and measured again from the USB casing to the gantry and got OL.

I then plugged in IHS and measured again and got OL.

I unplugged the IHS and then plugged in the THC and measured again and received 3.78 kohms.

I then followed the THC troubleshooting on this page underneath the flow chart ( )

and got the following results for volts

At the port on my razorcut 45


Then at the end of the wire connector leaving the VIM box that plugs into the THC port on the controller I got


2.812 x .685 = 1.926 which is really close to the number I measured.

Is it possible I have a bad VIM??

I unplugged my THC wires from the plasma unit and from the control box and checked for continuity with the VIM box still plugged in, I’m unsure if I did this right… when I check from pins 1-1 I get 46.9ohms

2-2 I get 1.869 ohms

Does this signify I have a short in those connectors??

Any help is appreciative and thanks for your time!