CandCNC LCTHC

[Carter3]

Just getting around to installing the LCTHC on my plasma table and was wondering if there is a problem with mounting the THC sensor card in the same cabinet as the LCTHC control board. This way I can keep everything neat with only one cabinet.

The cabinet is an 18"x18"x 6" hinged cover control cabinet and will have a gecko 540, LCTHC control board, THC sensor board, 48v power supply, 12v power supply and a fan. I already have everything mounted, but after looking through the manual on the LCTHC it shows the THC sensor card mounted in the plasma itself or in a separate box.

[jimcolt]

For safety reasons the sensor card should be in the plasma system. It has to interface to the DC output voltage, which can be as high as 300 vdc. Much safer to keep this voltage inside the plasma encolsure.

Tom at CandCNC would be the best person to answer this for you...



Jim Colt Hypertherm

[flyinwilly]

I agree with Jim. I mounted mine in a insulated enclosure (plastic box) and screwed it to the side of my cutter since I didn't have room to mount it inside. You should keep the tip voltage leads as short as possible.

If you do it this way, all you have to run back to the Lcthc is the DB9 cable. In addition, the torch relay leads will be much shorter.

Willy

[Carter3]

Originally Posted by flyinwilly I agree with Jim. I mounted mine in a insulated enclosure (plastic box) and screwed it to the side of my cutter since I didn't have room to mount it inside. You should keep the tip voltage leads as short as possible. If you do it this way, all you have to run back to the Lcthc is the DB9 cable. In addition, the torch relay leads will be much shorter. Willy

I have the same problem of not having room inside the cutter. Not a whole lot of room left inside a PM45 and I didn't see a good way to mount it to the side.

I didn't think that the length of wire on tip leads would be a problem (2ft vs 15ft). I used 16 awg twisted pair(600v rated) on that connection. That is also a separate cable from the arc ok and start wires. I don't think that having a high voltage DC wire in the cabinet would cause any interference but was going to have it routed separate from all the low voltage and AC wires anyway.

Thanks for the input and keep it coming. Hopefully Tom will chime in and give his input.

[jimcolt]

Running the DC voltage (electrode to work connection) outside of the plasma cabinet is more of a safety issue than anything else. These connections will have full open circuit and load voltage, as well as full cutting amperage. The voltage can be 300 volts DC, the amperage can be whatever the plasma system is rated for....so safety if more of a concern, and that is why it is best to divide the arc voltage inside the plasma enclosure where it is developed, and exit the system with a safe voltage that is a fraction of the level.

Jim colt Hypertherm