Re: encoder to tach converter idea (was killer deal...)

<snip good stuff>

> The DAC is not the big concern, it is the change in velocity

updates

> with the
> encoder.
>
> Jon

Got it. I understand what you mean now when you were talking about
the lack of information with encoders vs tachs at slow speed. I
didn't realize a tach that was like 5V per 1K rpm would even have an
output at 0.001 rpm...I assumed any voltage generated by the tach
would get lost in the noise level of the circuitry or cables. So at
what point does the resolution of an encoder match that of the best
tach? I have 2500 line encoders (10,000 in quadrature) on my cnc
mill motors, and I have to think that is pretty dang good. Even at
0.1 RPM, I would still get 16 counts per second. 0.1 RPM would be
about 0.02 IPM on my mill.

But if I had 200 line encoders, or even 500 line encoders, then I
could see where there could be problems.

Thanks for the explanation.

Rick