Double gang Two lights

[PBC_1966]

So now the question is, can I wire the switch how I would like without the permanent live.

Not unless you would like it to only work when another switch is on.

Do we even know if the two lights are on the same final circuit? Even if one permanent live is available at the switches, using that could result in the whole "borrowed neutral" mess.

It's really time to trace out what's actually there. Pictures at the two light fittings might help.

 

[Risteard]

They ALL are and therefore identified by their presence.

Presence tells you nothing. After all, cpcs must be present at switches and neutrals might be. I do not need to know that it is a permanent or switched line, but you are required to identify that it is indeed a line conductor. This isn't optional.

 

[PBC_1966]

And in a neighbouring county it is actually forbidden to oversleeve brown & blue.

The ETCI National Rules for Electrical Installations actually forbid reidentification of conductors, so you have to start off with the "correct" color throughout the cable to begin with? Is it permitted to sleeve black and grey with brown for 2-way switch drops etc?

 

[JohnW2]

Is it permitted to sleeve black and grey with brown for 2-way switch drops etc?

Interesting question. If the answer is 'no', then I wonder whether 'triple brown' cable is available?

Kind Regards, John

 

[winston1]

a totally different over-sleeving colour to indicate 'sometimes line potential, sometimes neutral potential' might have been a better choice!

Kind Regards, John

Absolutely. In France and maybe elsewhere switched wires are orange or mauve.

 

[Iggifer]

Is it permitted to sleeve black and grey with brown for 2-way switch drops etc?

Interesting question. If the answer is 'no', then I wonder whether 'triple brown' cable is available?

Kind Regards, John

Well, as you well know, black and grey are already phase/line conductors, so oversleeving them must be ok! Triple brown cable would be impossible to work with. Imagine working on an intermediate switch on your own, you'd be back and forth belling out the cores.

 

[PBC_1966]

It is completely and utterly irrelevant whether it is always energised or not. The fact is that people know that it is a line conductor and therefore at a potential of 230V to Earth. They also know not to connect it to the system neutral which is at Earth potential.

If you open up a switch and see either red & black or brown & blue going to the two terminals of a single-pole switch, you should know that both are live (or potentially so, no pun intended) and that the black or blue is not a neutral (just the same as if you see black & white on a single-pole switch here you know the white isn't neutral).

Surely the purpose of color coding conductors is to assist in identification? If it's clear what purpose the wire is serving, then the job is done. It could be argued that using twin brown rather than brown & blue on a simple switch drop actually hinders identification, since once one end is connected you can't easily tell which wire is which at the other end. With brown & blue (whether or not the blue is sleeved brown), it's easy. Of course, in this case it's hardly a big issue since you can easily test and if you're just connecting to a single 1-way switch it doesn't matter anyway, but nevertheless, if one insists on following that "preferably" clause, it actually makes identification harder.

On a related switch drop issue, under the "old" system, with red/yellow/blue (or the older red/white/blue) to a 2-way switch I'd say that the yellow (or white) & blue were probably not sleeved with red more often than they were (at least in residential systems). Did/does it matter? You know that in an installation fed from a 2-wire single-phase supply they can't be other phases.

As Winston noted, in countries where singles run in conduit are common even for residential work, it's also very common to use different colors for 1-way switch returns, 2-way travelers, etc. And why not if it helps to identify different conductors? Isn't that the whole purpose of color-coding them in the first place?

 

[PBC_1966]

Triple brown cable would be impossible to work with.

With British-style triple & earth it would work, since with the earth conductor as a reference it's easy to match up end to end. But obviously harder when the sheathed part of the cable is buried at the back of the box and not so easily visible, and open to more chance of error than having three different colors (whether some are sleeved or not).

 

[JohnW2]

Well, as you well know, black and grey are already phase/line conductors ...

Whilst that is true, I thought it was only true in terms of 3-phase applications. I have always understood Appendix 7 to be saying that line conductors in a single-phase system must be identified by brown.

Triple brown cable would be impossible to work with. Imagine working on an intermediate switch on your own, you'd be back and forth belling out the cores.

Quite so - exactly the observation I was going to make had you answered 'yes'!

Kind Regards, John

 

[deadshort]

I've swapped the connector to make sure it was OK.

How its wired at the moment I have permanent light in the back and the front room light can be switched on and off lol.

I think you have a short across the switch cable which is bridging out the switch for the back room light. If work has been done in room check that the cabling to the switches has not had a nail or screw put through it!

regards,

DS

 

[ban-all-sheds]

They also know not to connect it to the system neutral which is at Earth potential.

 

[Risteard]

Is it permitted to sleeve black and grey with brown for 2-way switch drops etc?

Absolutely not.

 

[Risteard]

Well, as you well know, black and grey are already phase/line conductors, so oversleeving them must be ok!

The only colour for a line conductor in a single-phase circuit is brown, so it absolutely isn't OK and is forbidden.

 

[securespark]

Surely it's OK if they are sleeved in brown?

 

[Risteard]

Surely it's OK if they are sleeved in brown?

Under ETCI Rules?

No - it is prohibited.