Re: CNC knocking out phone system?? Help!!!

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "rogersmach" <rogersmach@y...>
wrote:

> Hi all,
> My CNC machine is knocking out the phone system. I dont know if
> its always done this or it just started but, when the servo motors
> are on, the phone system loses the dial tone. Is there some sort of
> RF filter I can install in the line from the wall to isolate other
> electronics in the building? They are on separate circuits. It seems
> to be effecting all circuits from the Main electric panel. I
> confirmed there were no encoder cables in questionable proximity of
> the AC lines inside the CNC enclosure. It's feeding back somehow.
> Thanks in advance.
>
> Ron

Ron:

If you are assuming the problem is caused by conducted noise rather
than radition then a line filter on the input of your CNC package may
work. They are available from many sources, Corcom being a large one.
Digikey carries them. Make sure the current rating is large enough.
Thjey come in bascially two types, IEC320 (that's the kind of power
socket used on PC's) and wired in. Get a general purpose model and
avoid "medical grade" because they don't have nearly as much filtering
capability.

I would question if something might be wrong inside your controller.
It's unusal for that much conducted EMI to get through the power
transformers and into the line under normal conditions. If that is in
fact happening then a good line filter should work.

Regards;
Ken