Kinetix 6000 Drive Soft Limit Fault Action

I'm using a Kinetix 6000 to drive a ballscrew. The axis was jogged into the maximum negative soft limit and the drive faulted. The fault action is set for "Stop Motion". We could not clear that fault (#16) or execute MSO without getting an error. We had to change the soft limit, then jog out of the over travel condition, then reset the soft limit back to the correct value.

Questions:

If the soft limit fault action is set for "Stop Motion", will that stop *all* motions in either direction until the axis is no longer beyond the limit?

If the Fault Action was set for "Status Only" would this have prevented the soft limit over travel bit from coming on?

Maybe the better question for me to ask is, in general terms, what the best practice for managing soft limits and over travel in the logic? I'll need to fix this to keep it from happening again and I'm interested in what the "right" way to do it is.

Thank you.

Scarince,

AB has a published method for recovering from a Soft Overtravel. It is located at:

https://rockwellautomation.custhelp.com/app/answers/detail/a_id/21500

I believe a support account is needed to access it.

The gist of it is:

Disable the Software Over Travel limit checking using the SSV command.
Determine the direction to move the axis based upon the Over Travel violated.
Move axis in the reverse direction until clear.
Clear the fault conditions, including PosSoftOvertravelFault and NegSoftOvertravelFault.
Re-Enable Software Over Travel Limit checking using the GSV command.
Put the axis back in a Servo On state.

The technote has a code piece available for download.

This is a primary reason we try not to use Kinetix. I feel an over travel limit, whether soft or hard, should stop motion in that direction only. At least this should be a selectable behavior.

Kinetix soft and hard limits are for when something has stuffed up beyond the programmers control

eg hard limits protect toothed belt jump so position incorrect - or a fitter has been in the drive train

soft limits protect for when the operator can change positions dynamically - not just absolute positions but relative positions where you are adding offsets
It is useful as a catchall behind your programming that should not be reached

Your Jogging should have stopped before the soft limits - low speed, knew what position you are at - MAS the Jog - this allows you to program a "back out" using the other Jog direction

Soft limits are useless until the axis is homed (ie you know where you are)

Thank you all. This is *exactly* the kind of info I was looking for.

Thanks again.