Originally Posted by Al_The_Man  With a rotary axis, it is a bit of a problem to hard-wire in overtravel limits as all positions are valid, the exeption is over 360°, but this can only be decided in the controller, and technically you would not need switches to decide this, so this would be a control logic function.
Most controllers I am familiar with would shut down the axis if the encoder position was illegal (ran away) or the processor shut down.
Al. |
This was on a gantry machine, and the A axis pivots the spindle, and only has 240 degrees of travel (120 from 0 in each direction) and it did have limit switches, one for each limit. I see your point if this were a rotary table though.