Quote Originally Posted by glbreil View Post
Another bit of a worry, is that the DC servos on the machine now are 1.3NM and Centroid recommended the Leadshine ELM2 750 watt AC servo motors to go with the Hickory control. The new motors are rated at 2.39NM so, but looking at the physical size they are tiny in comparison to the Siemens DC motors. I have never had anything with AC servos, I guess that is the norm?

Thanks Gary
Not entirely normal, but some older servos were quite large things, but there were still some fairly compact ones.
I'd be more interested in how the torque/speed/inertia compares.

Inertia selection isn't an area I know much about, but I know when I asked somebody who was knowledgeable about it when looking for servos for my big mill, they advised to go for the larger 1250W servos, as despite the smaller 1000W servos having comparable performance to the original 1000W DC SEM servos, they said the larger frame size would be a better match and easier to tune.