Hiding meter tails in walls, sufficient mechanical protection

[1Justin]

522.6.101(iii) requires trunking 50x50 to BS EN 50085-2-1 .

But mechanical protection (iv) : We agree that mechanical protection is "difficult to provide" and we are advised here of 3 or even 5mm steel.

The lid of the BS EN 50085-2-1 trunking is not this thick, yet that trunking could be hidden in wall and used for mechanical protection. - So saying this, then could I use ONLY the galv lid of such, screwed in place to cover meter tails which were channeled into blockwork behind dot and dab?

(single brick wall, loadbearing, slightly dodgy, definitely not thick enough to risk channelling for 50x50 trunking)

.. I could of course go to the steelyard and get a length of 5mm plate, only it seems these nice galv lids are just available.

Justin

 

[Knobhead]

Unless you bond one of the lengths of conduit at ONE end only...

Sorry but it’s the circle of ferric (magnetic) material around a single conductor that forms the eddy current and the heat. You could get away with aluminium or copper tubing.
For every amp flowing through a conductor you will have 1 amp flowing around it in the steel.

 

[Deleted member 26818]

Could use single core non-magnetic armour?

 

[1Justin]

Actually, you will still get eddy currents in a tube round a single conductor, regardless of whether the armour is ferromagnetic material.
Even an aluminium or copper tube would have eddy currents.

 

[malcolmsanford]

Yes but aluminium and copper are not ferrous and so you will not get the same effect as you would with iron based containment ..............ie galv/black enamel conduit

 

[Amp David]

Just had to do a similar job. Meter is in a lower cupboard and move the CU up into a new wall mounted cupboard. Chased out the wall then screwed a steel plate to the wall, ran tails into chase then screwed another steel plate over the top.

Plasterer just dot and dabbed a piece of board over this section and used browning on the rest.

Steel was only 3mm though:shout:, but if someone managed to get through that using a masonary bit, then they deserve a little shock