earth grounding questions when using shielded cat5 & neutrikplugs

[acidbrain]

Hi fellow Diyers,

I have a question about earth grounding my system.

-All signal grounds are floating in each cabinet and star connected in the pre-amp. At that starpoint is a connection with the mains earth through an isolator.(2 diodes/ R & C)

-Each cabinet is connected to mains earth at my UPS in starconnection.

I realized that I have 2 shielded Neutrik cables go from one chassis to another chassis, both are on each side connected to the chassis and therefore connected with the mains earth, cousing a loop. Not only between them but also with the earth. The lenght of both cables is just 40cm.
Do I have to cut both cables shields at one end ?

The same thing with my cat5 shielded cable, I can connect both shield-ends to the 2 chassis. Should I just connect one end of the cable to earth to prevent a groundloop ?

This is not a signalgroundloop, but it doesn't look healthy to me.

Anyone who can help me in the neverending story of grounding ?

[AndrewT]

Davenport in Articles.

[acidbrain]

Very informative article indeed, but I can't find anything about the behaviour of parallel safety grounds. I just cut all ends at one side, to get rid of any loop.

[Speedskater]

No, don't cut the shields, it truth they are good. Tony Waldron sometimes writes about them. He calls them PEC (Parallel Earth Conductor's) they should all follow the same path and be about the same length. In Recording or TV studios, the more the merrier.

[acidbrain]

Hi Kevin, I googled on PEC and found a lot of info about old and new ways of earthing equipment. It looks like I can(must) earth both ends, but I need to add a PEC between the cases to minimize the earthloop. Hmm, maybe not in the case where I use already 2 Neutrik cables only with the single cat 5.

Thanks for getting me on the right path



Bonding Cable Shields at Both Ends to Reduce Noise

Designing for Interference-free Audio System Components

http://www.vanderheide.nl/documents/...ntHandler.ashx