Encoders for Mesa 5I25

Hello, First post, thanks for lettin me in.

Want to ask if US Digital E6 optical encoder , differential output is a good choice for Mesa 5i25 and DC brushed servos?
What cpr should I go with?

Thanks, Dave

www.usdigital.com/products/encoders/incremental/rotary/kit/E6

Should be fine, any resolution is OK (usually the higher the better)
to make full use of the differential outputs you need a daughter card that
accepts differential inputs (7I77,7I76, 7I78, 7I85)

Yes I was figuring on ordering a 7i77 also. Thanks for the help. US digital has that E6 at a max of 2500 cpr so I will go with that.

Thanks, Dave

There are some limits:

Those encoders are limited to 300,000 cycles per second = 1.2 million quadrature counts per second, which is 7200 RPM max with the 2500 CPR = 10000 count/rev encoder

OK in your opinion is there a happy medium cpr number where going higher doesnt really add any measurable benefit? 500 or 1000 cpr ?

Thanks, Dave

It depends on the usage.

For a servo system (typically no more than 3000 RPM or so) the higher the better

But if this is for a high speed spindle, you may need to
chose lower resolution to allow higher speeds.

Don't mean to derail the thread but I have basically the same question kinda.... I am doing a Bridgeport R2E4 Series 1 boss 9 retrofit. I have Linuxcnc installed along with a 5i25
and a 7i77 installed and everything looks ok for now.

My questions is can I use the existing bei encoders on the bridgeport as I am using existing servos and amps also. I cannot find any build logs that would help.

Thanks in advance,

Bob

If they are 5V TTL or differential 5V signals they should work. These are the most common type of rotary encoders.

Some types known not to work directly:

Encoders with sine/cosine outputs (Heidenhain linear scales are a good example
(these need an interpolator to work)

24V quadrature encoders (these can be made to work with voltage dividers)