Bandwidth limits and electronic gearing?

What is the recommended solution for high resolution rotary encoders at high spindle speeds.

I'd like to interface a 17-bit encoder, but that quickly exceeds the 10Mhz bandwidth of Mesa's 7i47.

It there a tried and true encoder divider, or is this a DIY project?

Thanks
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Is the encoder absolute? If so the 7i74 is not suitable as it is intended for incremental ones.

Typically higher resolution encoders use serial interfaces instead of quadrature

The 7I47 can support either quadrature or serial encoders (with RS-422 interfaces) depending on how its wired

A 7I44/7I74 makes more sense for serial encoders from a wiring ease standpoint

Hostmot2 fiirmware currently supports SSI, BISS, and Fanuc type 1 serial encoders

Note that a 10 MHz signal limit means a ~40 MHz quadrature count rate with a 17 bit encoder (~18000 RPM).
Its also very unlikely that a17 bit quadrature encoder has better than a couple MHz bandwidth
so basically its _very_ unlikely that the 7I47 is the actual limiting device

OK. Thanks.

This encoder is (was) on the spindle of a lathe. I



The encoder was moved due to a broken belt.



'm pretty sure the unit is a Heidenhain, but it only is marked with the manufacture's part no.



This machine has a Reeves drive, two speed motor and two speed gearbox. It would be neat if I could determine both the spindle speed and the spindle position with just this encoder.

But you seem to be hinting that beyond a certain spindle speed this encoder goes blind? ~2200 RPM is mentioned in the manual?

Thanks.