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I am not sure if this question has been addressed. I had a request to terminate an outdoor cat 6 cable between two buildings. If there is no metal sheild on the cable both ends of the cable protectors are to be grounded? I understand that if there is a metal sheild then only one end need to be grounded the other end floats. Please advise if I am right or wrong. Thanks

The shield should only float in a situation where the cable doesn't exit the building. In a two-building scenario, yes you should bond the shield at both ends to the protectors and connect them to the building's electrical service ground.

But if one of the buildings has a bad ground, won't the sheild act as ground path?

'But if one of the buildings has a bad ground, won't the shield act as ground path? '
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Which is a subject for another thread and has been addressed before. HOWEVER, if you suspect a bad ground it is NOT your responsibility, as a 'phone guy", to fix it. That is 'sparky's' responsibility! >BUT< you should advise your customer >IN WRITING<, with a signed copy in your files, to protect yourself!

Yes, Wayne. I agree with your logic. At the same time, we can't forecast and avert such issues. Frankly, I'm not a fan of bonding building grounds via telephone cable sheaths for this very reason.

I'm not sure about how Canada's electrical code addresses this. The US electrical code (NEC) has become much more involved in this area over the past few years.

The NEC allows certain exceptions for the use of separate 'neutral' and 'ground' requirements as long as there is no other metallic connection between the buildings. This can be water, gas, conduit, telephone cable sheath, or anything else. In a perfect world, the ground potential differenence between two buildings is zero volts, but that never happens due to variations in soil conditions. There is always a difference.

Your situation is a classic example of the chicken or the egg. On one hand, bonding both buildings together via a cable sheath could easily result in a complete failure in the event of the electrical/grounding issue. On the other hand, having the cable at a possible different potential (voltage) with a floating end from the local ground could be a shock hazard. A shock hazard it a bit of an extreme, but it can happen.

It is really up to what the CEC has to say. How about making a call to the local inspection agency to get their feedback? That might be your best bet to cover yourself.

Thanks for your help.

Yes.i think you shall ground the shield conduct,take a pole on the shield conduct,and connect a wire to earthing ground.