Re: [CAD_CAM_EDM_DRO] Servo or Encoder problem?

mmurray701 wrote:

>I'm in the process of upgrading from steppers to servos and have
>come across a slight problem. I've finished my control box
>containing the power supply, Geckos and all the cables and tried it
>(on the bench) and everything seemed to work fine. After some more
>testing to today I noticed that one servo performs erraticly at high
>speeds. Two of them run fine up to nearly 4000 RPM but one seems to
>shake and cause the drive to fault after about 2000 rpm. This
>problem is in the servo as I tried it on another drive/input. I'm
>just wondering if its the encoder or the motor? Everything works
>fine at lower speeds. What could be causing this? Thanks in advance.
>
>

Well, what is different about this one? Are they identical motor/encoder
units? Is the cable longer on this one? Is the cable of a different
type on
this one? If it works at low speed, it is somewhat unlikely the motor or
encoder are bad. But, it is possible that the encoder, especially, is
marginal.
Some people have had problems with noise on the encoder circuit. One
fix was to put a small capacitor, around 10 uF, across the 5 V power
connection, right at the encoder. Did you use shielded cable for the
encoder? If not, you might try that.

Jon