MAch 3 touchplate script error

[KenR]

Use a jumper wire to apply gd to that terminal and see if it works on the diagnostic screen. If it works that way, you may need to run or repair a ground wire to the spindle? Some spindles have ceramic bearings and you must use a ground clip on the bit. It's just process of elimination. If it won't work with a jumper wire, maybe use a different input and change the pin assignment in Mach to match.

[gills]

I decided to start with what input I knew was working and lighting the led light on the Mach 3 diagnostics page, which was my e-stop. So on my controller box I plugged my E-stop cable into my touch plate connector and my touch plate cable into my E-stop connector. I engaged my E-stop and the pin number for the touch plate in the BOB light up on the diagnostics page. SO now I know that particular pin location does work. So I touched my tochplate to the spindle and nothing lit up on the diagnostics page. So Ger21 is correct that it is a conductivity porblem. SO after checking the spindle cable connections to the VFD and the spindle all appears to be good. My TP cable appears to be good but I decided for the sake of change, to replace the magnent on the end of the cable which I use to connect to the spindle collet, with an older alligator clip which I don't like. I have used the magnent for several years now without issue until now. So After clipping the alligator clip to the bit and touching the plate to the bit, it lit up on the diagnostics page. So I ran the touchplate script and it worked. I know Avid CNC ond other touchplate makers use a magnent for the spindle connection, what would make the magnent stop working? I do appreciate your knowledgeable suggestions Ken and Ger21, thank you

[KenR]

You can try touching the touchplate to different parts of the frame and see if it works anywhere. If you have an ohm or continuity meter, you can track it down and see where your issue is. Anyway, at least you are on the right path and you can use the clip if you can't fix it with a better ground.