atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring Tie Cable

I've been asked to spec and run a 50 pair tie cable between two buildings (span is aprox 50ft). I've been asked to spec this as well. How high should I run the cable? The building is one story about 15 feet.

I don't know much about things north of the border, but 18' is required above a commercial driveway here in the states under the NEC guidelines. You might want to check to see what the CEC has to say about this situation. I'd imagine it would be similar.

In the U.S., the maximum legal height limit for a truck is 13 feet, 6 inches. In order to allow for sag, 18 feet is considered to provide enough of a safety buffer. Of course, over four feet of sag is a bit of a stretch (no pun intended) even with major temperature extremes.

50 feet at 15 feet in height should be sufficient, but again, it's what the CEC mandates that will call the shots. I'd run this question by a local sparkie to see if masts on the buildings will be required to meet the U.S. requirements.

I think the question is will it cross any area that is accessable to vehicles. If so and even if the driveway or parking area is off limits to trucks, you always have to consider that something 14 feet high will go through there.

So, the answer is if your run is over a lawn or walkways then you are OK with 12 feet of clearance from the LOWEST point. Any vehicular traffic and you want at least 15 feet, again measured from the lowest point.

The NEC does not have anything to say about outdoor LV runs other than the clearance that must be maintained from service drops.

-Hal

Bury that sucker if you can. 'And that's all I've got to say about that.' (With thanks to Forest Gump) John C. (Not Garand)

Don't forget the primary protection. The NEC chapter 800 has something to say about that.

I would suspect that similar rules apply up there, too.

Thanks, what I was wondering was minimum clearance. So aiming for 15 ft at the lowest point should do it. LV here is covered by the Electrical Code of Ontario.

Wish I could bury it. It means digging and boring the parking lot. They want a buried quote too so I'll get them that as well ( I don't have manpower or the equipment). I also have to run a network feed too a buried conduit would be ideal.

Thanks again.

You could always call 1-800-GOJULES

On 2nd thought, let's keep him south of the border....

Dave

Marv, you may be pleasantly surprised at the cost of a bore. Just make sure they can control the depth. Older equipment tends to ride right up against a parking lot slab, which = no significant mechanical protection! John C. (Not Garand)