What size cable to feed consumer unit??

25mm tails sound tad to much for 1-2 bed flats.
Your whoesaler is probably talking about about 16mm tails and posibbly a 10mm main earth cable? but what do they know.

Run 3 core 16mm SWA and you'll be fine. After all how and where is the cable going to be run.

Get a timeserved sparks in and not a 5 day part-p I was ex forces or a milkman cowboy.

 

16mm swa

 

what size is main fuse ??

 

Central Heating is?

 

Get a timeserved sparks in and not a 5 day part-p I
was ex forces or a milkman cowboy.

Now Now P&E I take exception to your comments, you cant tar all milkmen with the same brush :^O
On the serious side not all Ex forces are cowboy sparks you know

 

personally i would install 16mm T&E with a 10mm earth cable to each. You'll need to terminate into a 60a switch fuse at meter end, cuz run over 3m, (click make the same one as mem but 20 quid cheaper) and then you can run straight into plastic fuse box's within each flat. I you use swa you'll have to either use a metal clad fuse board or terminate into a box before. Also i wouldn't chase this size cable into wall but run up with some large trunking

 

personally i'd install 16mm 3core armoured terminated in metal clad 60A switch fuse in meter cupboard and then terminated in standard consumer unit complies with 17th too

 

oh yeah and put it in the wall dot'n'dabbed of course we dont want to chase too deep !!

 

I would say we don't have enough info to give a considered reply about the size of the cable required. In particular: 1) are the flats all electric or part leccy part gas - affects overall loading and switch fuse rating and 2) distance of the CUs from the meter point - is this a Victorian semi in the middle of town or an old cotton mill (ie huge)?

Choice of cable type will be mostly down to sparky preference and installation method employed.

Question though (I'm doing my 17th in a couple of weeks): do these submains need 30mA RCD protection if they are buried (less than 50mm deep)? If so, isn't this a problem with each flat entirely on one RCD?

 

I have seen a similar installation using 25mm2 split concentric cables.

ie. the line conductor 25mm2 in the centre and neutrals adding up to 25mm2 and cpcs adding up to 16 mm2 around the outside.

As these cables don't really need to be armoured they are small and do a great neat job.

Yoda

 

I would say we don't have enough info to give a
considered reply about the size of the cable
required. In particular: 1) are the flats all
electric or part leccy part gas - affects overall
loading and switch fuse rating and 2) distance of the
CUs from the meter point - is this a Victorian semi
in the middle of town or an old cotton mill (ie
huge)?

Choice of cable type will be mostly down to sparky
preference and installation method employed.

Question though (I'm doing my 17th in a couple of
weeks): do these submains need 30mA RCD protection if
they are buried (less than 50mm deep)? If so, isn't
this a problem with each flat entirely on one RCD?


using armoured cable means no rcd needed thats why i say run 16mm swa

 

or as yoda says use split concen

 

split con is far too expensive. Yeah it's easier to handle, but what a waste of dough. As others have said, 16mm swa is fine in most cases. If in doubt, run it in 25mm.

 

what size is main fuse ??

finally someone asks a relivant question

 

Brain box , the only way to do this is carry out proper calculations . without knowing what your design current is , the length of run or any correction factors it is impossible to say for definite.
Once you know the above you can calculate the size of cable required.
It will also be worth knowing what capacity the electricity provider has and if the fuse can be uprated.
If it was my flat to keep for a few years id probably go for the 25mm swa.

 

in this situation how will you go about metering each flat so the leccy bill will be charged to each flat?

 

Hi,

In a conversion of a property to flats, the 3 phase
head is to be located in the communal entrance
together with isolator switches. The consumer units
will be located some distance away within each flat
on each floor.

Which cable should be used to connect the consumer
unit to the isolator switch?

If the unit was in clos proximity, I'd of used 25mm
tails, but that's not practical here. My electrical
wholesaler suggests I'd be ok with 16mm T&E as flats
are only 1/2 bedroom unit.

Or should I use 25mm armoured?

Any advice appreciated.

Hi M8..done the same thing you are doing some time back..

16mm SWA is quiet sufficient..

1 x switchfuse per flat in corridor meter cab etc etc..

25mm SWA is not indicated.

Thanks.

 

Jeezus feckin wept.

Is it any wonder real electricians sometimes find it quiet when you have wannabes offering their services for stupid prices.

I mean how the fek can someone price and get a job without knowing what they will be installing?

Do the people who reply to these questions not realize what they are doing?