On 01/14/2017 11:00 AM, Cecil Thomas wrote: > > > My noise source is the G320's PWM generator which switches at 20 khz. > > I'm still not sure how such a horrible noise signal gets from the 48 > volt motor armature switching circuit in the G320 to the input of the > 7i78 Yes, the Gecko drives have no filtering on their outputs, and any unfiltered FET half bridge switch is going to radiate a LOT of RF, due to the fast switching edges. All my servo amps have LC filters on the output to try to hold the noise inside the amp.
The Gecko drives do have optoisolated step and dir inputs, but the enable is NOT isolated. Also, on the G320 series, the encoder inputs and encoder power pins are not isolated. So, any common connection to these will bring noise into other systems by direct connection. You could use a relay to isolate the enable connection on the G320s or other Gecko drives. Then, you would not have a galvanic path to the rest of the system, but wire arrangement could still couple lots of signal. Jon ------------------------------------------------------------------------------ Developer Access Program for Intel Xeon Phi Processors Access to Intel Xeon Phi processor-based developer platforms. With one year of Intel Parallel Studio XE. Training and support from Colfax. Order your platform today. http://sdm.link/xeonphi _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
