Customer has welding equipment in the shop. He wants us to install two cat5e shielded (rightfully so) cables through the shop to extend a T1. One cable for spare. I will install as far away as I can from the welders. I will use shielded cat5e jacks of course. What is best practice for grounding?

Run metallic tubing (EMT) or metallic flexible raceway (FMC). Ground the metal at both ends. Use standard non-shielded Cat5e.

Arthur -

I have always only grounded circuits at ONE end (the closet side). Reason being, that the ground potential may not be the same at both ends thereby causing more problems then not grounding the circuit. While it's probably not as serious when grounding conduit, it can be disastrous when grounding shielded cable.

Also, forT-1, I would run approved T-1 cable, not Cat 5E.

Sam

Yes, when using shielded cable for audio, ground the near end, and not the far end. All metallic conduit in a building is assumed to be at the same earth potential, just like the rest of the electrical plant in the building. The multiplicity of conduits guarantees it.