Index (Z pulse) Homing on Delta Servos
I hope it's OK I add a bit more info to this thread specifically in regards to Delta servos. I bought some used ones quite cheaply. To me, it's a better deal than the no name ones as the Deltas have much better documentation and a proper tuning/setup software. (Actually, I am almost sure at least some of Automation Direct's servo series are rebranded Deltas, too.)
Earlier in the thread PCW mentioned a potential speed issue where the Mesa input may not be fast enough to read the index signal unless the index is somehow slowed down. But perhaps the following tidbit I found will help with this (it's from a different controller manufacturer describing
how to wire up index homing
):
For proper operation it is necessary to rearrange DELTA drives default settings. Number of pulses of drives’ output encoder – should be shifted to a lower value to ensure adequate INDEX signal pulse length. P1-46 parameter set by default on 2500 pulses – set on 500 pulses per rev or less. This change has no influence on servo drives working precision because their internal procedures work on encoder full accuracy anyway.
PCW also suggested on email that I slow down the homing speed (home to regular limit/home switch can be faster, but then slow down the home to index/Z pulse after that). So, maybe a combination of lowering the pulse value for the encoder and slowing down the home speed a bit is the ticket.
Again, if you have B3s, A2s or perhaps A3s(?) you can try making the servo drives handle the homing routine.
