sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring Customer installing their own underground 4" PVC 1200'

Ed, I wasn't sure if you have to run UF cable through conduit...never worked with the stuff. I'm told it's not fun.
You would have liked the job they did...dual 30 amp breaker in the house running out to a sub panel with 4 20 amp breakers, so we can put lights and garage door openers in.

Thanks Hal - The people at West Penn were great. Very helpful. I will order their shielded waterproof audio cable for the run.

The contractor that is doing the trenching will install three 1.25" innerducts through the 4" PVC. We will then be the people pulling the fiber, 50-pair, and audio through two of them leaving one for the future. Will use OSP cable; knowing that water/elements will work their way into the pathway.

It works out to 1130' feet, with about 650' of that underground. The rest in running through their giant building to get to the data room. They are debating having the innerducts exposed in the inside runs vs running the 4" PVC all the way.

You are aware that the OSP cable must be terminated/transitioned within 50' of entering the building, correct?

Conduit all the way!! And the 50' rule doesn't apply if it is in conduit.

Jeff-what Ed said.

-Hal

The reason I mentioned the 50' rule is because Noisycow stated, "They are debating having the innerducts exposed in the inside runs vs running the 4" PVC all the way."

He is still suppose to abide by the 50' rule if he is using PVC or innderduct.

It probably is a moot point. I doubt any inspector is going to notice how the communiations cable is installed. :rolleyes:

He is still suppose to abide by the 50' rule if he is using PVC or innderduct.

Innerduct, yes because it is not a listed conduit or raceway. But I don't remember the NEC making any stipulation as to what conduit could or couldn't be used. It just says "conduit or raceway". I'll look but I don't think I'm wrong.

But keep in mind that there may be local ammendments that prohibit PVC or limit its use within a structure.

-Hal

NEC 2005 800.113

Exception No. 2: Listing and marking shall not be required where the length of the cable within the building, measured from its point of entrance, does not exceed 15m (50ft) and the cable enters the building from the outside and is terminated in an enclosure or on a listed primary protector.

800.2 Definitions

Point of Entrance. Within a building, the point at which the wire or cable emerges from an external wall, from a concrete floor slab, or from a rigid metal conduit or an intermediate metal conduit grounded to an electrode in accordance with 800.100(B).

I stand corrected!

-Hal

I know FIS has fiber that is rated to go from outdoor to indoor without the transition and I'd rather not have to splice.

The cables could probably come into a box with backboard to transition the 50-pair to inside wire; and lightning protection terminals.

All major fiber cable manufacturers make indoor/outdoor-rated cable, so you will be fine there by using it. It is not much more expensive than standard outdoor fiber cable and much easier to work with.

With regard to the copper cable: Yes, it will need to be contained within listed conduit for the application since OSP cable is not fire retardant. In fact, it is quite flammable since it is not designed for indoor use whatsoever. The allowance of 50 feet is actually pretty generous in my book.