You don’t need the kit to work, but you’ll have to splice some wires and get into the machine to get it all hooked up. I didn’t quite catch if your machine had the cnc kit and it wasn’t installed, or if it didn’t have it.
There are two signals from the plasma you will need - torch on/off and voltage measurement. Torch on/off is needed in all cases, but the voltage measurement is only needed for THC. If you don’t have the cnc kit, you’ll have to tap the appropriate wires inside the machine so the THC can read the RAW voltage. It will then divide this by 50 to get the voltage in the range the controller works from (50:1 division).
Torch on/off is basically tapping into the same circuit as the trigger switch. The CNC controller will be pulling the trigger instead.
With the kit, all these wiring tasks are taken care of. No splicing needed. It even divides the voltage 50:1 so the THC doesn’t need to divide the voltage and provides an ‘Arc OK’ signal that is not used by this table, but many other CNC tables do.
I have the 625 with CNC kit. Let me know if I can help.