[ichudov]

I have this Troyke servo driven rotary table, model U12 PNC:

http://igor.chudov.com/projects/Brid...-Table-U12PNC/

I worked on it yesterday, as before it would not run. Now it does run (see page for details).

What I know about is that:

*) It is a rotary table
*) It is driven by a DC servo motor
*) It likely has a tachometer

Troyke has no info on this table. I was rather disappointed with their support for older products. But I digress.

Where I would like some help is in deciphering encoder wires. The bundle of encoder wires has two separately wrapped sub-bundles.

Bundle 1: Bare uninsulated wire, green wire, red wire
Bundle 2: Bare uninsulated wire, orange wire, purple wire, brown wire

I interpret the uninsulated wire as a grounding conductor for noise suppression.

My interpretation of the first bundle is that this is tachometer power. green is probably 5v minus, and red is probably 5v plus.

My interpretation of Bundle 2 is that this is the non-differential encoder output, as follows: (Bare is Ground, A channel, B channel, index). I have no idea how colors match the outputs.

I am a newbie to the CNC world and would love to hear more experienced opinions. Maybe I should junk this encoder and get one from US Digital.

Any comments?

[Al_The_Man]

The tach is usually two wires, if perm. mag, tach.
There is also a resolver shown in the pictures, this will be the feed back device, most likely.
Al.

[ichudov]

The tach is usually two wires, if perm. mag, tach.
There is also a resolver shown in the pictures, this will be the feed back device, most likely.
Al.

Al, should I try to retrofit some converter to this resolver, or would it be a better idea to somehow add a modern encoder?

The latter is a little tricky, as the shaft on the back does not extend beyond the motor.

What do knowledgeable people do in this situation?

Thanks!

i

[samco]

picosystems makes a resolver to encoder converter. (converts a resolver to quadature + index (a/b/z). Something to think about.

http://pico-systems.com/resolver.html

sam