Overhead Cable to Garage

[fastJedi]

Current Situation
I currently have 2.5mm T&E spanning a 1m gap between a gable end wall of the bungalow and a detached garage! Clearly, this is not good .... I need to correct it as part of getting the wiring upto scratch for a meter and CU move in the spring. I really really don't want to go underground as it is a tortuous route with a very thick concrete path between the two.

Option 1
32A MCB
4mm T&E across the loft into a junction box
4mm armoured cable across the span and into the garage CU

Option 2
Some kind of conduit bridge .... perhaps even a length of ali scaffolding tube!

Option 3
Build a wooden (or brick) archway to carry the cable

Advice please?

 

[Lectrician]

4 or 6mm split concentric directly from house CU to garage. Use pre-formed stays (sometimes called dead-ends) and screw-in eyes.

 

[slippyr4]

There are minimum heights too. Assuming that the gap is inaccessible to vehicles, the cable must be at least 3.5 metres up. The only exception to this is to use 20mm dia. steel conduit with PVC sheathed T+E in it. In that case, you can have it only 3m up.

Height ignored; PVC is ok if attached to a catenary wire.

 

[fastJedi]

But that's taller than my garage .......

 

[plugwash]

attatch a pole to the garage and mount it to that?

 

[slippyr4]

Of course, whether you do it to the regs is your choice.

 

[ban-all-sheds]

If you were to build a brick arch, or other permanent structure linking the two buildings and attach the cable to that (SWA or normal cables in conduit) then it would no longer be an overhead cable..

Height ignored; PVC is ok if attached to a catenary wire.

But not really OK to be exposed to the elements...

 

[slippyr4]

But not really OK to be exposed to the elements...

Maybe, but the Whitfield book talks about it...

 

[plugwash]

trouble with T&E is the pvc its made of isn't UV proof, it should be ok in sheltered situations outdoors but it can degrade in direct sunlight (though this still takes a long time).

the sheaths of stuff like split con and SWA that are typically used outside have something added (typically active carbon hence the black color) to stop the UV penatrating into the sheath and damaging it.

 

[Darkness]

The gap is 1m you say.

For that space you can go to the hassle of running a length of swa and terminating it or if it was me, just use t&e or stick the t&e in metal conduit.

I've just installed an overhead cable of approx 12m length using 16mm t&e. I couldn't use swa as I wasn't going to dig up my concrete yard.

If your just running the t&e without the conduit, don't worry about the weather affect on the cable however if it was for some reason on the ground, the weather effect on it is much greater.