I found something usefull the other day and thought I would pass it along. We have a Kia SKT 250MS with a 18-i. We had to arrange our tooling on the turret in such a way that it is severly unbalanced. We are a production shop and do not move tooling around very much.
The problem was when rotating the turret manually it would get stuck in between positions if you stop in the wrong spot ( all the weight in the 3 or 9 clock positions.) I found the parameter to adjust the amount of time between the clamp signal and turning the power off to the servo motor that rotates the turret. I increased this time setting and it works great now and is much smoother of an operation. It basically keeps the servo engaged longer and the turret in the correct position so the curvic coupling engages properly.
It is Parameter #168 under the PMM screen parameters.
I do not know if this addresses is common to all machines thou so you are at your own risk.
Also can someone explain a little more about the PMM side of the machine. Is it for the MT builders or is it a fanuc thing??
It's an O.E.M. thing. The turret drive is most likely a Fanuc beta drive (very small and less expensive).