Catenary wire

[jimbo81]

Hi all looking for some help. I was looking for the minimum height of a catenary over a road, i cant seem to find it in the regs, can anyone help? I need to know where to find it in the regs book, thanks for your help in advance.

 

[Octopus]

Not sure any Tom, Dick or Harry is allowed to install a catenery wire over a highway.

 

[snowhead]

Is the Public highway, No, No.?

Or private road, if so depends what traffic uses it, cars, vans, lorries, tractors.
It would need to be high enough to clear any foreseeable traffic.

 

[MDJ]

Agreed with the guys regarding highways haha, to add about the height, at least 20 foot I would have thought, some artics are 16 ft high now.

 

[rattlehead85]

There is a topic dedicated to this subject within the NICEIC online technical manual. Sadly though you need to be a member to access it. If anyone has a registration they can guide you. I can look later for ya if that helps. Off the top of my head i think the wiring has to be at 5.4 m above a road and i'm not sure you can do this if it is a public highway as you may be in breech of ESQC regs.

 

[MDJ]

Well I have the manual on CD, but won't bother looking for it, if it is vital then I can take a look next time I'm in the office OP.

 

[rattlehead85]

You'll have it online as well MDJ as part of your fee entitlement. Constantly updated to.

 

[JD6400]

The only reference i can think of is 705.522 (iii) " Self-supporting suspension cables shall be installed at a height of at least 6 m."

This is obviously section 705 so make of it what you will !?

 

[Adam W]

There's a table in the OSG somewhere, which gives you minimum heights for conduit and catenary wire with and without vehicular access.
If it's a public highway you'd probably need to check with the council.

 

[Guest111]

Table D2 lists the heights, and these are 5.8 mtrs for positions accesible to traffic,the maximum length of span varies according to cable type, just be aware of high level routes as the height may need to be greater.

 

[Rampantchilli]

And don't forge, the minimum height applies to lowest part of the wire, ie the bottom of the sag

 

[Steve_P]

Public highway, forget it. If not it's in the BGB/OSG. I was asked to do one on a farm track about a year ago to supply a new barn, ended up cheaper and easier to go under rather than over.

 

[JD6400]

We as a rule will not install a catenary on a farm , as the risk of getting taken out by a trailer or loader is so high .

This was one of the main reasons why we moved into trench less technologies as well to overcome the problems of ripping trenches through farm / stable yards .

 

[Steve_P]

That's exactly why we didn't. Turned out we would be better off erecting 2 comms towers to hang the cable off!

Having said that. The overhead at the bottom of my lane looks like it drops from about 4.5 to 3m or so. That's over a public highway.