Question - electrical sanity check

[nothanks]

I've laid underground SWA feeds from the house CU to a couple of sheds (and a Well area). The feeds have B20 MCBs at the head and RCDs at the load end; all remote CUs have TT earthing. One of the sheds is about 30m long and has a couple of walled-off areas down one end (used as log stores) without lights so I planned to run T&E from an MCB in the shed CU to a light switch in these areas. It's just occurred to me that I could run 1.5mm and use it for a single socket as well as the light. AFAICS there is no problem doing this using (say) a B10 MCB - thoughts?

(PS I've found a large roll of 1.5 red/black that it would be good to use-up)

[John Rumm]

Voltage drop permitting, no problem. 1.5 mm^2 T&E is good f0r 20A in its "clipped direct" installation, so a 16 or 20A MCB would be fine[1]

Might be slightly more elegant to take the lights from the circuit at the destination via a 5A FCU, but not strictly necessary unless the lamp fittings you use have a particular protection requirement.

Waste not want not :-)

[1] in fact if you have lights and only a single socket, there is no realistic prospect of overloading the cable anyway - so the actual value of the MCB is not that critical so long as it will still provide adequate fault protection.

[Vir Campestris]

<snip>

B****r. I took half a roll to the tip last year under the impression I wasn't allowed to use it any more.

Andy

[Chris Green]

Since our house has a mix of old and new colours I hardly think anyone is going to notice me using some old coloured cable on 'new' wiring.

[alan_m]

If you use your existing supply of red/black for any modification you just say that the work was carried out prior to 2000 :)

[John Rumm]

If it were a pro job for someone else, then you would not use it. However on your own place, going into an install that presumably has mixed colours anyway, who is going to care?

(I thought I had used all my old colour stuff long before it was even phased out, although I did find a nearly full reel of 3&E last time we moved. I still find occasional use for that)

[Owain Lastname]

Does it still sell for inflated prices on ebay?

Owain

[Andy Burns]

Either peel-off the manufactured date stickers from all wiring accessories, or "remember" an alibi for why you needed to replace them all after the wiring was installed ready for when the Part P police come knocking :-)

[charles]

I understood that if you put the appropriate sleeving on the ends, there wasn't a problem. - not that I have any left.

[Chris Green]

Yes, I have some 'old' 3&E still, it's much prettier than the new colours isnt it! :-)

[Robin]

Not for installations starting after 31/3/2006. But (rephrasing John Rumm's point) it'd be a /really/ odd DIY-er who used cable with the old colours and then shopped themselves.

[Dave Liquorice]

impression I

Probably better than weighing in?

[Andy Burns]

Apparently, yes

[Scott]

I would have bought it off you as I wanted to make some modifications without being too obvious.

[Scott]

Along with other collectors' items such as 7 amp fuses :-)

[No Name]

Really?

I know someone who has loads of T&E, 1.0mm2, 1.5mm2, 2.5mm2 and 4.0mm2 and possibly some 3+E too :-)

Think the postage costs would be a killer though....

S.

[No Name]

I know someone who has loads of 7A fuses along with 1A , 2A and 10A fuses.....

Postage should be trivial!

S.

[nothanks]

On reflection, I decided that the wiring inside the luminaires (reclaimed fluorescent light fittings) was the limiting factor so I've used a (reclaimed) switched fused spur as the light switch. All is now done. It's a Legrand CU but I only had an MK B16 MCB which, of course, has a different terminal height to the Legrand MCBs - easily fixed with a tweak to the copper busbar but I wish all MCB makes had the same physical dimensions.

[Scott]

Thanks, but the job is completed now.

[Dave Plowman (News]

Even if your house is still wired in it?

I'd not use it on anyone else's house, though, for new. But would for a repair.