Re: [CAD_CAM_EDM_DRO] Re: Agilent Encoder Pull-up resistor

Peter Homann wrote:

>Jon,
>
>That's just plain rude and offensive!
>
>The advantages of using differential signals are very clear. It's the
>reason why it's standard practice in a lot of the industrial control
>industry.
>
>
>
>

I agree that differential signals help reduce noise. Many lower-cost
CNC systems,
especially home shop-level, don't use them due to cost. All the lower-cost
encoders and servo motors with built in/on encoders, such as HP, US digital,
etc. are single-ended.

>Note to moderators: I didn't think this short of "Bashing" was allowed on
>this group.
>
>
>

If they really need differential signals for anything over one foot,
they must have
an electrical noise problem. As I say, I have worked with a number of
CNC systems
that have up to 30 feet of encoder cables, and they work fine without
differential
drivers.

I can see some reason for Rutex to recommend this just to cut down on
support
calls. Certainly, when Joe Metalworker tries to hook up a Rutex drive
to a plasma
table with 30+ feet of unshielded single-ended encoder cables, he's
going to have
a problem.

Jon