Garage electrics

[Andypease1]

Below the gravel is solid concrete. No chance of any work in that area could lay warning tape on top.

"There are no problems only solutions"

Cheers
Andy

 

[mfarrow]

You want something that will get in the way of the cable man's spade before it hits the cable.

Cleat the cable onto the concrete, apply warning tape, then put say some overlapping roof tiles over before putting the gravel back.

 

[JohnW2]

Cleat the cable onto the concrete, apply warning tape, then put say some overlapping roof tiles over before putting the gravel back.

Reasonable (I would personally be comfortable with that in my house), but I'm not at all sure that roof tiles would offer adequate 'mechanical protection' (for a cable buried at only 75mm) to satisfy the regs - and, don't forget, as I said this is probably notifiable work.

I've asked several times but no-one has yet offered a view as to whether cable in steel conduit buried at 75mm would be compliant with regs.

Kind Regards, John

 

[EFLImpudence]

I've asked several times but no-one has yet offered a view as to whether cable in steel conduit buried at 75mm would be compliant with regs.

522.8.10

 

[JohnW2]

I've asked several times but no-one has yet offered a view as to whether cable in steel conduit buried at 75mm would be compliant with regs.

522.8.10

Thanks - but as I wrote last night, I'm temporarily separated from my regs, which is why I had to ask about this. Could you outline what it says? In common sense terms, I would have thought that mechanical protection adequate to resist a spade ought to be OK at any depth.

Kind Regards, John

 

[EFLImpudence]

It says:

Except where installed in conduit or duct which provides equivalent protection against mechanical damage, a cable buried in the ground <usual conditions>. Buried cables, conduits and ducts shall be at sufficient depth to avoid being damaged by any reasonably foreseeable disturbance of the ground.

 

[Andypease1]

Looks like I am ok and it does not specify plastic or metal conduit.

Many thanks to all

 

[EFLImpudence]

Plastic conduit offers no mechanical protection.

 

[Andypease1]

Said that tongue in cheek. Will use good quality metal

Cheers

 

[JohnW2]

It says: Except where installed in conduit or duct which provides equivalent protection against mechanical damage, a cable buried in the ground <usual conditions>. Buried cables, conduits and ducts shall be at sufficient depth to avoid being damaged by any reasonably foreseeable disturbance of the ground.

Many thanks - that's what I suspected and vaguely recalled. It therefore sounds as if the OP will probably be OK so long as he uses proper steel conduit. In theory, I suppose he could use T+E within that?

Your quote says "...which provides equivalent protection...". Do the surrounding bits give any indication of 'equivalent to what'? Sorry about these questions - it's frustrating not having access to the regs!

Kind Regards, John

 

[EFLImpudence]

Except where installed in conduit or duct which provides equivalent protection against mechanical damage, a cable buried in the ground shall incorporate an earthed armour or metal sheath or both, suitable for use as a protective conductor... Buried cables, conduits and ducts shall be at sufficient depth to avoid being damaged by any reasonably foreseeable disturbance of the ground.

 

[JohnW2]

Except where installed in conduit or duct which provides equivalent protection against mechanical damage, a cable buried in the ground shall incorporate an earthed armour or metal sheath or both, suitable for use as a protective conductor... Buried cables, conduits and ducts shall be at sufficient depth to avoid being damaged by any reasonably foreseeable disturbance of the ground.

Thanks again - but I don't really understand, do you? It appears to be saying "equivalent protection against mechanical damage" to earthed armour or sheath. Since that makes no sense, I am still left wondering "equivalent to what?"

Kind Regards, John

 

[EFLImpudence]

Agreed. It would appear to be just referring to electrical protection as swa (despite the name) does not really offer much (any?) mechanical protection, does it?

 

[Andypease1]

Seems to me twin and earth in metal conduit is acceptable. Due to the wording it would stand up in court. Also does not say it has to be burried

 

[EFLImpudence]

You may be right but then swa does not have to be buried.