15m Industrial Plasma Cutter

How much of that 14kg is the 6m lead?
Though it's maybe worth bearing in mind that if you put the power supply on the gantry then the earth lead needs to come off on the cable chain.

But the earth lead might cope better with the flexing.

14Kg ????
I had an italian made inverter 45A plasma, it was 38Kg with cables.

Put the electronics on one side of the gantry, you need only a power and ethernet cable. Get a switch mode power supply, it is lighter than any version of toroidal/rectifier/capacitor combo ( it is lighter than only the rectifier with cooler and capacitors ).
How did you get to 6M for the cable on a 15M machine ?
You will have to put the plasma on the other side of the gantry ( never on the same side with electronics ).
That ends up needing a power cable, a network cable and an air tube in long dimensions, and makes for a neat machine.
Some things are not negotiable at that size.
Or maybe i missed something and you are doing a smaller one ???

Hi Tommy,

The cutting length is 12m so I only need 6m if the plasma is in the middle. So I thought that a 10.7m torch would handle it.

Jarman wrote: Hi Tommy,

The cutting length is 12m so I only need 6m if the plasma is in the middle. So I thought that a 10.7m torch would handle it.

In theory yes, but reality has a way of messing things, like bends and attachments to other things and it can not be very near the moving machine etc.
You also need another 3 meters for the gantry and the Z as they will have to move and bend, so need some slack.
12 should be the minimum, and even that might prove quite problematic to route properly.
Try the Trafimet web site, i did get some 12M ones with machine torch for something like 500 euro a piece here and they are of very high quality.

shop.trafimet.com/en/products/PLASMA/Automatic+torches+HF/

With regard to leaving the cutter in operation, the existing industrial CNC at the company are monitored while in use but they are largely very reliable. How easy is it for a hobby CNC to be built with this kind of reliability and are there specific things that I should be aware of (like shielding and dust protectors etc.)

LinuxCNC controls many machines that are definitely not Hobby machines. Tormach is one example of an industrial one You could follow my lead and add a stacklight so you can see status from a distance.