View Full Version : Servo fault handling

23-09-2013, 04:39 PM
I'm looking for peoples thoughts on handling servo faults.

I had planned on linking the e-stop circuit so if a drive faults, it cuts all the power. However, the issue with that, is the drive would then fault because of low voltage (the logic is on a permanent 24V supply), and would prevent the e-stop being reactivated until the drive fault terminals are bypassed and the drive sent a fault reset signal. Which is doable, just that it would involve a bit additional coding to get things to reset, however I'm not sure if Mach could actually handle it...

However I'm thinking it would be far simpler to just link the fault outputs into the KFlop, then programme it to halt things if something faults. The drive enables are going to be controlled by the KFlop, and I'll probably connect the drive fault resets as it'll mean avoiding having to power everything off if something does fault. Then I'll watch the drive ready and drive fault signals, and halt things if either of signals change.

There are limit switches on the two axis (these are on a lathe), which are tied into the e-stop, however it is a lathe and the carriage/tool is likely to hit the chuck long before the limit switch!

Anybody got any thoughts?