Is This Encoder Compatible With Centroid Acorn?

[ChrisMe]

I’ve finally selected the encoder I want to run on Centroid Acorn and before I buy it I thought I’d check to make sure that it will work.

Here is a link to the PDF-

https://encoder.co.uk/core/files/encode ... el_702.pdf

I was going to buy it with the following features-
Channels- Quad + Z Marker (i.e. A+B+Z channels)
Output Type- Open Circuit
Maximum Frequency- 1000Khz
Connector Type- 9 Pin D-Subminiature (I should be able to connect this to Acorn easily with a cable)
PPR- 30,000 (can acorn handle this many)

The additional part the sales guy wrote was “30,000 pulses per revolution, A, B, & Z channels without compliment signals, single ended NPN Open Collector output circuit, radial mounted 9 pin D-Semimature”

Will this work? Thanks for the help.

[tblough]

Nope. You need 5V line driver (RS422) signaling. The open circuit output type will not work with any Centroid equipment. You want the HV output type, and Centroid recommends around 1000 lines (4000 pulses per rev) for a spindle encoder. Frequency = (rpm*linecount)/60) so, with the 7500 line encoder you've chosen, you will be limited to a maximum spindle RPM of 1000000*60/7500 = 8000 rpm. Whatever encoder your choose, you'll most likely have to terminate the DE9 end yourself. I have not found any that are wired according to Centroid's specification.

There a quite a few threads on the board about selecting spindle encoders. Might be worthwile looking at some of them.

[ChrisMe]

Nope. You need 5V line driver (RS422) signaling.

Thanks for your reply. It was a very helpful reply. I'm going to look through the forum and read up more.

I think I'll order it with the correct output and with 5000ppr (20,000 lines) as that will give me a max spindle speed of 3000rpm (1,000,000*60)/20,000=3000) which I don't think I'll ever be going over.

When you say terminate the ends do you mean I'll need to look at acorns wiring diagram and solder my own cable? Thanks.

[tblough]

Yes. You'll need to solder your own cable.

[Muzzer]

That looks reassuringly expensive. How much are we talking for one of those?

[ChrisMe]

That looks reassuringly expensive. How much are we talking for one of those?

With the incorrect specifications I mentioned above I was quoted-

2000 ppr- £181
4000 ppr-10,000 ppr- £221
30,000 ppr- £271

I'm not sure if those prices are inclusive or exclusive of VAT