Newbie- Motion Control Cards - Encoder Inputs

[Billiam]

Hello,

I'm looking at a Galil motion control card that has dual encoder inputs per axis. I'm guessing it's for motor encoder + linear scale inputs. Okay, great.

So how does this work with a typical AC servo drive that also has encoder inputs (CN2)?

Thanks for answering my n00b question!

[Al_The_Man]

It depends on the drive you are using, if the drive has encoder inputs, it can be for commutation or tach feedback.
Often a drive of this sort would have an encoder output that could be used back to the Galil controller.
Find out if the encoder input is optional or not to the drive.
The bottom line is you need the encoder(s) to go back to the card if dual or single encoders are used.
There are some AC drives that have resolver feedback from the motor and output a pseudo encoder output that is available for the CNC controller.
Al.

[Billiam]

Thank you Al. I downloaded the instructions for the Automation Direct servos and they do indeed have outputs for A, B, Z phases in the CN1 terminal. Makes sense now!