valid arc lost program is paused

Thanks for the reply but I tried that(arc-lost-delay 0.3) and add the debounce as well as mentioned in the first post but it didn't help. I also tried to change from Mode 1 to Mode 0 but same result. My problem is if I use M62 P3 command, I will get the error message. Is there anything else you want me to try?

I "think" the problem is that you disable the torch, move a short distance then enable the torch again before moving again. It would most probably error when you enable the torch again as the should be no Arc OK signal. For example in the square:

You are right! I moved the line "m63 p3" to the end of the file and no more the valid arc lost error message. So that means I need to modify a Gcode file manually every time I run it? Is there any way to do it automatically by adjusting somthing in Sheetcam or the post processor?

You would need to edit the rules so that the torch turned back on after the last move.

So you mean editting the torch off before end path rule in the plasmac.tools file, not the post processor file? I am sorry to ask but how I can do it?

Sorry, I cannot help at the moment, my SheetCam tried to update itself and now it is trashed...