CU

[evdama]

Is it acceptable to the electricity company to have the meter and consumer unit fitted inside the porch rather than inside the hallway?

 

[ban-all-sheds]

If the porch is totally enclosed, I don't see why not - after all they have meters completely outside these days.

BUT if there is any chance that water could get onto the meter and/or CU, e.g. if the porch is not enclosed, or rain could come in if you open the outer door when it's windy, then you will have to ensure that they are given the appropriate IP protection (x3 or x4).

The only thing I would say is that having the CU in the porch means an awful lot of cables coming through the wall instead of just the meter tails....

 

[evdama]

Thanks ban-yes its a lot of work but the wall that the existing one is on is a half timbered one which is rotten as a pear and has to be dismantled for either replacement or restoration .Theres a horrid collection of rewireable -fuse boxes and I am going to get the power co. to change the meter anywayso its an ideal time for a fresh start

 

[ban-all-sheds]

Well, obviously I've got absolutely no idea about your physical constraints, but if I was going in for a fresh start with wholesale move and replacement of CU and meter I'd try to have the CU indoors.

Don't forget to have the electricity co fit an isolation switch.

 

[evdama]

Ah! - Why indoors then?
I would really like it all completely away from the building work which is pretty involved.

Ive got a MEM switchfuse ready to go in.
Ive also seen service blocks in scr***** cataloguge-how does the wiring get arranged ? theres a single pole and a double pole version but what gets done differently?

 

[ban-all-sheds]

Purely because of the number of cables that would have to go through the wall. You have 2 wires going into your CU (3 including earth), but a multiplicity coming out - a 12-way CU with all circuits used, including say 3 ring mains is going to have 15 T/E cables coming out of it ranging in size from 1 or 1.5mm up to 6 or 10mm.

If you put your CU outside the house, you'll have to take 15 cables through the wall.

A service block is simply a plastic box containing a thick metal bar with holes and screw terminals so that you can connect cables together. It's made with big holes and thick bars so that you can use fat cables like meter tails carrying up to 100A.
They are just large, high-current junction boxes - this is what a single pole one looks like inside:

A double pole one is bigger, and has 2 metal bars inside so that you can connect 2 lots of cables together - Live and Neutral tend to be handy.

They are used if you're feeding more than one CU, or a CU and a dedicated shower unit - you take the wires coming out of your meter into the service block (or blocks if using single pole ones), and then you have 4 wires coming out (2L, 2N) i.e. one pair to go to each of your CUs or shower units.

If you are doing this remember you must use 25mm 6181Y meter tails

coming out - just because, for example, you've got 10mm running from your shower unit that doesn't mean you can use 10mm running to it, as that 10mm would only be protected by the main 100A fuse - a bit dodgy.

 

[evdama]

Thanks, ban. - thats fantastic.There is means of blanking the unused ports I take it?
If its just a case of extra hard work then Ill go with the porch thing as a 6x6 hole is pretty insignificant in the overall scale of things on the agenda.
Its just I didnt want the Supply company refusing to connect me back up because its against the regs.
Ive read two books, one based on the 15th and one on the 16th and neither make reference to such location.
Cheers

 

[ban-all-sheds]

There are no "unused ports" - the side of the box has knockout sections which you use to make the holes you need.

I don't know what the regs say about a CU in a porch either, but I expect there's something about exposure to the elements.