Splitting T&E Supply

[Darkness]

I have a 16mm2 t&e feed going to an outbuilding which feeds an old MEM fuse cartridge CU. This is being ripped out as the building it covers is being tossed. Two new outbuildings are being built adjacent so I was planning to fit a new CU in each building splitting the 16mm2 supply to each CU.

What’s the best/tidiest way to split this 16mm2 supply, have it safe and ready to feed the other two buildings? Must be IP rated. Supply is protected by 100mA RCD so I was planning to fit 30mA RCD in both new CU.

Thanks.

 

[EFLImpudence]

Is the cable long enough to reach into the first new CU? If so, connect at the Main Switch and Earth bar.

Everything has an IP rating, what IP rating do you need?

 

[Darkness]

No. It doesn’t reach. I prefer it on the existing wall away from the two new buildings. The two new buildings are either side of this one.

Needs to be weatherproof to keep possible air moisture and the usual bugs and crap out you normally find in outbuildings.

This current MEM is a mess inside.

 

[ericmark]

I know twin and earth is often used outside, however it is not rated for use outside and it is hard to find stuffing glands that will seal on that profile, you could pot the cable but cable joints are not cheap, and the question is if worth putting a joint like that on a cable which should not be outside to start with, the outer sheaf can split and allow water to follow the inner cores into the joint.

So in real terms if you do fit a joint it needs to be in doors there is little point using an IP65 joint on a cable not designed to be used outside.

 

[Darkness]

Let me clear this up better.

No t&e is outside. SWA underground and enters the building at the rear via the roof space. The swa is glanded into a metal box and joined in it with this run of 16mm2 t&e. The route to the old cu is a nightmare hence why they used t&e.

Just an awkward layout. Maybe in the future I’d knock this one down with the digger and have a straight run to the CU.

 

[securespark]

Everything has an IP rating

My undercrackers don't.

 

[securespark]

Seriously, how far is the SWA joint from the two new sub board sites?

I might be tempted to run two new SWA feeds from this point. How big is the SWA and what is it protected by other than a 100mA RCD?

 

[EFLImpudence]

Not sure what undercrackers are but - IP00 ?

If they are what I think then surely they are IP69.

 

[securespark]

Men's underpants!

Darkness...can you take some pics or draw a diagram to explain proximity, positions etc...?

 

[Darkness]

I didn’t get the cover of the metal box but first looks, it could be 25mm, but 16mm if not.

Just wondering would I be better to just stick a new weatherproof CU in and fit a 100a Isolator. Then just branch from a 32a mcb etc to each new building?

At the end of the day, this CU will give me the option to add a light in this building and maybe a socket. Could make this a split board.

 

[conny]

Is the swa being fed from the CU in the house, and if so, what is the protection for it? (32A mcb, 20A etc)

If not fed from the house where is it getting it's power from?