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Unread 18-01-2012, 12:10
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Re: How fast can KOP encoders count?

Quote:
Originally Posted by Mr. Rogers View Post
We wanted to track the live rpm of our ball shooter shaft, turns about 5500 rpm max, could a 250 or 360 count encoder count that fast? (198000 counts per minute) (33000 counts a second) (using a 360 count.) Anybody know where we could find a single count encoder wheel (1 count per rev.), or could the software keep up at 33000 counts a second?
The encoder itself should have an rpm rating, but that's usually more of a mechanical issue then electrical.

The true limit on encoder counts is the cRIO.

I don't know the official upper limit, but Austin Schuh on 254/971 has quoted me that a 64 count encoder on a CIM 1:1 (5300 rpm) works. This is ~5600 counts/second.

For velocity control at such speeds, you really don't need that many ticks per second.

A single "tick" encoder could be made with various forms of light sensors, hall effect sensors, etc...