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

skykotech wrote:

><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.
>
>

I think your encoders are certainly good enough if you're not making
lenses and mirrors with it.

Jon