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In my house the lighting circuit is made up of
One live and earth in same sheathing. Then 2 separate neutrals.
I haven’t seen this arrangement before and I’m wondering what this is.
 
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telectrix

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goes back to 50's and early 60's. lights wired in singles. red/cpc for L's and blacks with no cpc for N's. this was so as to take L's to switch/es then to light/s without it being tied in to the N, which went direct to light/s. the next light would then have L from 1st switch C to C of 2nd switch etc.
 
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At the light there’s one live and 2 neutrals so this is where I was encountering the problem. Obviously the neutral carries on to the next light but where’s the live the live that goes to the next light?! Don’t know if I’m over thinking it as I can’t work it out
 

telectrix

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the L goes to the 1st switch, then is looped from switch to switch, each switch supplying a S/L to it's light. sometimes there may be junction boxes hidden away.
 
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the L goes to the 1st switch, then is looped from switch to switch, each switch supplying a S/L to it's light. sometimes there may be junction boxes hidden away.
So the lights aren’t in a series (daisy chain)? Sorry I’m really struggling to find a diagram online.
 
Yes seen this once before on a house built in the 1950s

Single red (imperial) with bare earth in grey sheath with a separate black at the lights

Very odd configuration and only ever seen one house wired like this
 

snowhead

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Nothing unusual about that cable.
It was in use untill at least 1988 when my house was wired from new with it.
My first house in 1972 had it as well.
 

littlespark

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if its single red (or black) with bare cpc in grey sheath, I know the number for it is 6241Y... like T&E is 6242Y

Im sure it was called "Single and Earth"... like twin and earth or 3 core and earth
 

telectrix

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it's simple.red with cpc goes into C on sw#1, the to sw#2 then sw#3 etc, each switch then feeds switched L and cpc to it's light. the N's are looped through at the lights.no need for them to go to switches, and no need for cpc on the N singles.
 

DPG

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My house is the same, ie. Red+earth and then separate neutral. There's also a traditional round junction box in the loft which I am going replace with either DIN terminals or wagos. Mind you I've been going to sort it out for about fifteen years now.
 

freddo

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Some areas of the UK used this method of wiring quite a lot, there is a local 'care home' wired in such a way. I used the same single and earth cable in my house to wire the switched live to all the switches that are overridden by the smoke alarms.
 

ipf

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My house is the same, ie. Red+earth and then separate neutral. There's also a traditional round junction box in the loft which I am going replace with either DIN terminals or wagos. Mind you I've been going to sort it out for about fifteen years now.
Why change. If it's installed correctly and cable is good, the odds are it'll be OK for another fifty.....
 

ipf

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There's nothing unusual.....or old about single red/brown and earth.
One regular use was/is for wiring 2-way lights. Strappers between switches, two live and earth's from rose.....one to each switch, one L, one SW/L. Basic stuff.
 

DPG

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Why change. If it's installed correctly and cable is good, the odds are it'll be OK for another fifty.....
I know what you mean, but to be honest it looks shocking. The way they've done it is loads of live/earth all spidering out from this junction box.
 

Lucien Nunes

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When wiring lighting with insulated and sheathed singles, there is a tendency to form induction loops as the line and neutral take different routes around the building. This doesn't happen with most T+E as the current in one conductor (e.g. L) balances that in the other (e.g. SL or N), nor with conduit as although the L & N loop in different fittings, they usually return with their partner to the same trunk route.

Compare 'conventional' 2-way, where current flows to one switch, to the other switch via the strappers, and back to the ceiling rose, creating a large window area within the loop, with 'conversion' 2-way where it flows to one switch, the other switch, back to the first switch and back to the rose i.e. always returning along the same physical route and confining the area of the loop to within the width of the T+E.

Induction loops radiate intereference from whatever current is flowing round them. Before CFLs and LEDs, this was just pure 50Hz, but now with SMPSUs in LED lamps with perhaps rather skimpy filtering, there is a wider spectrum of RFI that the loop might radiate.

Does anyone now avoid wiring in singles not confined to conduit, conventional 2-way, and other unbalanced cable runs specifically because of this?
 

James

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Lucien, you have a good point.
There is a requirement to design installations so as not to produce excessive emi
Food for thought.
 
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