What do you mean by only 4X support.

Typically, the incremental quadrature encoder has A and B channels with
pulses 90 degrees out of phase when rotating. Not only does this allow for
the decoding of direction information but also allows for a pulse rate four
times that of either channel. Hence the 4X.

If a servo drive only supports 4X then the step frequency required from
software to support any encoder RPM is;

(RPM/60)*CPR*4

If the encoder is mounted on the motor shaft as opposed to a driven shaft
geared down from the motor shaft then you have a worst case scenario in
terms of required software step rate. If the highest step rate from software
is less than the above when RPM is the maximum RPM of the motor then the
motor will never be able to reach top speed.

1X support will reduce the above requirement by a factor of four.

"Eric R Snow" wrote in message
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