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Pete C. Pete C. is offline
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Default Some success with a servo drive/tachometer mode


Ignoramus30064 wrote:

On 2010-07-10, Jon Elson wrote:
Ignoramus30064 wrote:


Karl, you and Ned have convinced me.

I am actually very happy, because I would get rid of a lot of cables
inside the control box, less complexity, less fear of tachs going bad
on me and the drives going berserk, etc.

I will use torque mode.

One last question, if someone could enlighten me, whi torque mode and
not "voltage mode"?

I am not trying to invent a better wheel with 4 minutes of experience,
or think that I know better than everyone, I just want to understand.

Why ruin what you already have working? What is the resolution of your
encoder?
Calculate what velocity will have less than 10 encoder counts coming in
per second,
and if this is any rational velocity like you might have while orbiting
a circular path,
then you will descend into stepwise movement. Don't fear a tach,
they've been used
for 50 years now in motion control systems.

Jon


Jon, my encoders are sinusoidal and thus I believe them to be
incompatible.

i


Er, you got the US Digital ones to install in place of the old ones,
didn't you? You certainly aren't going to get your CNC control working
without working encoders.