Are there any regulations regarding electricity meter boxes?

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I'm building a pair of semi detached houses. The houses share a walkway and a lobby area 2m x 4m. When applying to the DNO for a grid connection the DNO recommended I dig a single trench on the shared part, put a hole through the wall and they would lay a single 3 phase cable to which would be attached 3 meters - one per house and one for power to the shared lobby area (or spare/unused)

I've dug the trench where they specified and put the relevant 115mm ducting in but now the query is over the construction and siting of the meter box. The rep from the DNO (it's outsourced to a local approved contractor) says he's only ever fitted meters to the off-the-shelf boxes and doesn't know of any regs surrounding the construction of an alternative. he also thinks 3 meter boxes will be required but there simply isn't space for 3 boxes on the wall where they will be mounted. I was hoping to be able to build a custom sized box for them something like 1000x1500 and mount it 500mm off the floor. The reason I'm wanting to make a box custom is that this is conversion of an industrial building and I have a door 1000x1500 off a former water pressure meter cabinet that has a few nice looking pressure dials surface mounted in it, and hence would make for a nice "meter cabinet" door

As far as I can tell from various DNOs there doesn't seem to be a prescription as to what a box is made of, its wall thickness, resistance to fire etc so I'm half minded to just make a sturdy cabinet with all the necessary access points, mount it on the wall and tell the contractor to crack on and fit the cable head inside it so I can get a MO to come in..

A related query to this, in terms of length of meter tails, this box will probably be between 6 and 10 metres away from where the consumer units will be located. I used to live in a flat where the meters were under the stairs but the CUs were in the flats, so I'm assuming there's no problem with having 10m meter tails if the voltage drop is within tolerance (which may involve using large cross section wiring and potentially with the need for some kind of cutout/safety device in the meter cabinet (in case someone drills through the tail??)

Can anyone advise if a) this is the case and b) the sizes of the equipment that will need to go in the meter box - i.e. will the cable head, 1phase meters, 100A fuse, any additional cutouts plus cabling etc fit inside a cabinet 1000 x 1500 ? What's the minimum size board for mounting all the required components? Should I just mount the board on the wall, leave the walls, floor, roof and door of the cabinet next to it so the DNO has more working room, then complete the cabinet in their presence (I can probably design it so it will assemble quickly with a couple of screws)

Many thanks
 
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can you not stagger them one above the other 2 like a piramid
or indeed stacked one above the other or at an angle like stairs??
 
There never was a meter box that could easily take a 3phase cut-out & 3 meters so building one is a sensible solution.
The three separate boxes suggested by the contractor is a bit of a no go as the means of isolation (the main fuse) should be in the same box as the meter it feeds!

As for fire proofing, the boxes are fibreglass with a fireproofed chipboard meter board so something along those lines should be aimed for, other points

See if you can fit a standard meter box lock to the built option to allow for easy access by DNO/MOP/Meter Readers.

Once connected up ensure each meter is clearly labelled to show what it feeds

Oh, and the maximum recommenced length of tails from the meter to a CU is 3m, so you should plan to fit a suitable fused switch at or adjacent to the meter for any that are longer than this distance. On this point you would not be permitted to fit this in the DNO box, if you have made your own that then is a different matter
 
Round our way are plenty of houses that have been converted to flats, with all the meters in a large cupboard in the entry hall.

PJ
 
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As for fire proofing, the boxes are fibreglass with a fireproofed chipboard meter board so something along those lines should be aimed for, other points

I do have a large metal cabinet, as it happens, and I also have a large selection of complicated brass fittings for where the cable goes into the box (saved from all sorts of thicknesses of SWA cables that were fitted to said box for the telemetry equipment) which I could offer up for the DNO to use? Presumably the box can be earthed and all is acceptable (I read some advice leaflet from a DNO that discussed mounting meters on a metal plate if the wall was thin, so mounting on metal is presumably allowed?)

See if you can fit a standard meter box lock to the built option to allow for easy access by DNO/MOP/Meter Readers.
I wasn't planning on fitting a lock but if I do, that's a good point, cheers


Oh, and the maximum recommenced length of tails from the meter to a CU is 3m, so you should plan to fit a suitable fused switch at or adjacent to the meter for any that are longer than this distance. On this point you would not be permitted to fit this in the DNO box, if you have made your own that then is a different matter

Sounds like own-box is the way to go then, thanks!
 
(I read some advice leaflet from a DNO that discussed mounting meters on a metal plate if the wall was thin, so mounting on metal is presumably allowed?)

True, but you will find most meter operatives unequipped to put a meter on a metal backing, so I would suggest a fireproofed wooded board. Similarly DNOs may be unhappy about mounting a cut-out on metal, again we are generally not set up to do so
 

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