Re: [Emc-users] US Digital encoders?

[Viesturs L. <vie...@gm...>]

2012/1/31 Peter C. Wallace <pc...@me...>:
>
> The three phase PWM is a fair noise source. Not just capacitively coupled
> noise from the three motor wires but inductively coupled noise due to
> current spikes from the 28V PWM driving into the motors winding/frame
> capacitance. This can be mitigated by putting a common mode choke (Big
> ferrite bead) over the three motor leads (DO NOT include the ground lead)
>
> Please try the encoder sample rate lowering example I provided. This will
> quickly help to see if there is a noise problem. Noise piked up by the
> encoder wires either inductively or capacitively tends to be short pulses.
> By lowering the input bandwidth a lot of this kind of noise can be filtered
> out.
>

Thank You, Peter and guys!
I am really starting to think that I should do some additional
testing, before spending any additional funds.

Viesturs