Servos, drivers, break out boards

[HereinCS]

I buy lots of linear slides for different projects. They all have different servo motors and encoders. Does a servo motor/encoder combo require specific driver? Can use a sanyo servo motor/encoder with a mitsubishi driver? Are the outputs from the drivers pretty much standard? Can I use any driver with a break out board and have it work with mach3? Thanks.

[jsheerin]

>Does a servo motor/encoder combo require specific driver?

A given motor and encoder will generally only work with certain drives.

>Can use a sanyo servo motor/encoder with a mitsubishi driver?

Possibly - depends on the details.

>Are the outputs from the drivers pretty much standard?

For a given type of motor and level of performance, pretty much.

>Can I use any driver with a break out board and have it work with mach3?

Probably not. Once again it depends on the details. Example:

I have a Fanuc AC servo motor with a 2500 pulse per rev incremental differential encoder. This will work with a Granite Devices drive because that drive is designed to drive AC servo motors and work with incremental encoders. Further, the drive has features that will let me set up step multipliers so that I can get a reasonable speed out of the motor with that encoder. The drive will also accept step / direction input (which is what Mach puts out), so I should be able to use a typical breakout board and have this work.

With this same motor, if I use an AMC brushless servo drive as commonly available used on ebay for not much money, I need hall sensor signals from the motor or encoder in order to get this combination to work. The Fanuc motor does not supply these signals so this won't work. However if I changed the encoder to a type that had hall signal outputs, then I could get it to work. Al the Man has some posts on this in case you're interested. However if I used a Yaskawa AC servo motor, that has the hall signals available from the encoder and this would work fine as long as I supplied an external source of 5V power to the encoder as the AMC drive doesn't have a large enough current capacity in its encoder power supply to run the encoder on this motor (for the particular drive and motor I have anyway). Additionally, the AMC drive will only take +/-10V analog input to control the drive. Mach doesn't provide this, so I'd have to get a special interface card that would provide this type of drive signal (although I think EMC might be capable of doing this).

For another example, if I have the Fanuc motor and a Geckodrive G320, they won't work together at all as the Gecko is designed to drive brushed DC servo motors, not AC servos. Additionally it can't handle the high pulse rate of the encoder given the limited step pulse output frequency from Mach, or at least it wouldn't be able to drive the motor to a very high speed. However it will work with all the typical step/direction breakout boards.

In summary, there are a lot more options when you start looking at servos as opposed to steppers, so you've got to be sure all your parts will work together. Hope that helps.