Re:Mesa 7i77 differencial encoder connection.

Thanks again PCW ! And thanks for heads up as well !

I have uploaded the file at filebin.ca and updated previous post as well.

filebin.ca/1UQcJ0K53d6/schematic.pdf

The ZOC pins appears to be a open collector version of Z (index) signal
not sure what its good for

hey peter

just a quick question on this same issue this thread is the closest thing to what I want to know.

I have the same setup as above. I am using my servo drive to output the encoder outputs to the mesa 7i76 spindle encoder card.

as far as I understand the drive powers the encoders and the mesa card doesn't need 5v connected.

so here are the questions:

1 do I need to use a signal ground at all if using differential encoder signals?


2 I am currently powering the 7i76 5v logic power from 5i25 is that going to be a problem if connecting encoders?

I will attach a screen shot of the encoder stuff in the manual.

here is the manual I am asking about. I have a build thread that may be a better place to ask and if so just let me know and I will ask there.

Becksvill wrote: 1 do I need to use a signal ground at all if using differential encoder signals?

The input common-mode range for the encoder is -7 to +12 volts relative to signal ground. You night need a common gnd to ensure that this is not exceeded.

Measuring the gnd offsets with a multimeter might be worth doing initially.

awesome! thanks andy

that is a very good piece of info to know

I just checked between the 24v io ground on the mesa card and the logic power ground and they are within 1.5 v

So I am good to go.

connecting up now.

regards

Andrew