Re: [CAD_CAM_EDM_DRO] I hate limit switches!!!

The best way to terminate shielded cable is to 'ground' ONE end only of
each shield wire at a point closest to the ground plane of the signal's
origin i.e. for those signals coming from the computer, ground to the
computer's ground plane (not necessarily the chassis). For the motors,
ground to their respective ground plane at the power supply, etc. The
important point is to only ground one end, thus avoiding 'ground loops'. In
the end, maybe you can connect all the 'grounds together, if it's necessary
to create a 'common ground'. But only if it's necessary.

RayHex

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> From: andrebarclay <andre.barclay@...>
>

Snip>

> My setup is as follows. I have 3 non-metallic flex conduits (bad
> start). One carries the shielded cable for the 3 motor encoders
> lines, the second carries 3 shielded cables for the power to the
> servos and the third carries shielded cables for the limit switches.
> All cables have a drain wire and a foil shield. The cables that carry
> the encoder wires have an additional wire "netting" around them. I
> have tried grounding the drain wires from all the cables to the
> machine, the computer case and every other configuration I could think
> of and, although I get some improvement here and there, nothing seems
> to eliminate in completely. The cables for the encoders have 8 wires
> in them not including the drain wire. Since I am only using 4 of
> those wires. I just folded back the extra wires and taped them off on
> both ends to the insulation. Could these wires be picking up noise
> and if so, what is a quick fix rather then replacing them?
>
> Thanks
> Andre Barclay