Plasma Cutting Arc Voltage Lost During Cut/IHS Fail: The torch did not reach the material…

Going to reach out to support but figured I’d ask here as well:

I was cutting a job this evening, and got this error:

Plasma cutting arc voltage was lost during cut loop.

Retry cut and it doesn’t work. Eventually trying to work through that, the first time, got to a screen that suggest a possible firmware flash on the THC. Did that. Kept Happening. When it happens, I’ll eventually land on this as the final error/alarm:

IHS Fail: The torch did not reach the material within programmed travel.

This series of events happens mid-cut. Once it happens, none of the axes will move at all. If I try to jig the machine though, the DRO/position changes on screen, even though the machine isn’t moving at all. It won’t move until I disconnect the USB from the computer, close Fire Control, turn off the control box, turn on the control box, connect to USB and reopen fire control. Sometimes that doesn’t do it and I have to click the reconnect to table button inside the software. Looking at the little troubleshooting side note in the documentation, seems like this might be expected behavior after an alarm?

Unfortunately it kept happening tonight - would be cutting for a couple minutes and then go out. Was cutting some small-ish pieces (about 5”x9” without a ton of detail). First time it got through a bunch of little wholes then failed at the end of the 6th piece. Next time it happened, it failed after the end of 2 more pieces. The next time it happened, it failed after 1 piece. Then I was able to make 3 more pieces but they were run one at a time.

Crossfire Pro
Fire Control 20.6
THC 1.1
Crossfire V1.2ls

Hypertherm Powermax 30XP

I’m having a similar issue where my torch is never touching the material and it only makes a cut for a couple of seconds before it faults out citing voltage loss. The torch never even cuts into the material, looks like its just sand blasting it almost. I’m using the pro but with the cut 45 cnc. I feel like it might be in my fusion360 settings?

lower the torch holder where the L in LS is just below the clamp. that should give you enough slack in the z axis for the torch to actually touch the material.


Good morning! I was able to succusfully cut something last night before I got out of here. Unfortunately I made 2 changes so I’m not sure exactly what the issue was. I moved the grounding clamp from the water table slat to the actual pc of 1/4" aluminum I was cutting, as well as rebooting the machine and my PC. Still trying to figure this all out, very happy to have the userbase here in this forum… and youtube lol.

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This is critical. Attaching to the slats or water table often leads to cutting issues.


@jamesdhatch is correct…putting your material clamp on the slats can cause arcing between the metal and the slats…I have seen metal actually weld to the slats…I have seen Aluminum get burn spots…not to mention it can throw off the THC readings