forum.cncdrive.com

Any one use plasma I discovered that when the thc is off it doesn't use arc ok input . So with out it table move faster than the plasma torch will fire ..so the fix now is delay the spindle m3 torch fire comand . 350 mili second . My question is there a way to have arch ok function with thc off .. I asked cnc drives they never answer emails .

You wrote your email yesterday, we need some time to answer.
My answer in email which I have just sent you:

"The THC command's exact purpose is to turn the THC signals (Arc ok, THC up/down) on, with the THC off the machine has to be controllable without the arcOK signal otherwise you could not move the machine at all without the arcok signal.
Why don't you just turn the THC on before the M3?"

And ofcourse add some THC delay (parameter) to inhibit the THC control while the torch starts the firing.
The THC delay parameter's exact purpose is to not allow the Z to be controlled by the THC up/down signals in the torch firing process when the THC is already on.

ok thanks for the reply thc some times need to be turned off like small holes . when that happens the m3 code fires the torch . befor the torch fires the table will start to move
and miss the start of a cut .. so what I did was put a delay of 350 mili sec in the m3 spindle delay now it works fine when thc is off with out arch ok
cutting small holes thers not enough time for thc control voltage to stabilize befor the hole is cut