Hi,

Using mach 4 2.1.2 with an avid pro cnc 4896 with 3hp spindle.
Getting this spindle ptc fault error and came to the forums here to figure out what the problem is.

The spindle stopped responding suddenly during a program run and thought the spindle was fried so replaced it. The replacement spindle isnt responding either. Ive reinstalled mach 4 and used avids SCU utility to configure the smooth stepper settings. This error is new and desperately need to get my machine running! Any help would be greatly appreciated.

The spindle PTC fault is a custom feature of Avid CNC's profile/screenset for Mach4. It's possible there is a wiring issue in the spindle's thermal protection circuit, somewhere between your spindle and control boxes.

If you haven't already been in contact with Avid CNC's support team, please email support@avidcnc.com and they can help you troubleshoot the issue.