Retrofitting into large CNC plasma table


I have a 16 year old CNC plasma table 3 metres wide x 9 metres long. The Hypertherm computer is full of issues. It runs Hypertherm Torch height controllers, one each for the plasma and oxygen heads. The company that built the machine is not around anymore and Hypertherm are not any help.

I have helpful circuit diagrams of the machine. I don't mind posting them because I think it will help others with theirs.

It looks like the Masso will talk to the torch heigh controller, then the torch height controller will talk to the power source. Ive read the torch height controller needs to know when the cutting torch goes around corners so the auto height doesn't dive into the work piece.

Can anybody help me with this?


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Staff member
Hi johnlittlejack

Only 1 of your pictures are showing. There is a size limit and the 3 missing ones might be a bit too big to post. you might need to resize them.

I confess I'm not a Plasma guy myself but this is how Masso interacts with the THC.

Masso can turn on and off the Plasma using a relay. Turning it on and off is the only signal Masso sends out to the Plasma

The THC when is sees the arc brings up the ARC OK signal to Masso as well as UP and DOWN signals which Masso uses to raise and lower the Z axis. When the torch is too high the arc voltage rises and a down signal is sent to Masso by the THC which then lowers the Z axis until the Down signal turns off. If the Torch is too low the arc voltage will be low and the THC send the Up signal which Masso uses to raise the Z axis until the arc voltage returns to normal and the UP signal turns off. The THC should have Anti-dive built into it so when crosses a previously made cut. The arc voltage will rise and there should be a delay before the Down signal is sent so that it can cross the gap without crashing into the table.

There are THC on and Off GCodes that enable and disable this functionality. As far as Masso and the THC talking to one another it is all one sided. Masso acts on the info it is sent.

There are several types of THC available and Masso will only work with some of them.

Hope this helps