THC turned off, cuts great

been having trouble with the voltage on the THC. Turned it off in fire control. Cuts great. What the hell?

Did you read and try the suggestions in your OTHER post on THC???

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I was in the same boat. I had no idea what I was doing wrong with all of the wiring. I did the same thing just to see what would happen, and low and behold, the TCH works perfect. There went about 9 months of lost production. But it’s working now so I guess there’s that.

Lets clarify that the THC is not what probes the metal and sets the pierce and cut heights. Those functions are part of the IHS(initial height sensing) system and they work with any table that has a powered Z axis.

The THC only has one job. That is to take a voltage reading at the start of a cut loop and move the Z axis up and down to keep that voltage within the specified range. It needs to get good voltage readings in order to function properly.

If you turn off the THC in Firecontrol, it is no longer looking for those voltage readings, so you don’t get the associated errors. The table will work fine with just the IHS system, as long as your steel is relatively flat and you don’t have any long cut loops.


i wonder if people are not dropping the torch holder down far enough and thc is getting a high reading to start with making bad cuts.

then if not low enough the ihs switch can keep lifting torch to a cut height.