Wiring replacement pull cord switch

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In any event someone posted how to connect the new switch a few posts (pages?) back, so have you fitted the new switch yet and does it work?
 


Been at work so not fitted yet (in any case I was interested to see how the debate on here pans out :) ).

So a standard fan was replaced with a timer fan, the existing fan cable appears to be reused instead of being replaced.... what does his invoice say? If it mentions replacing the cable, then I would recommend you get him back to actually replace the cable..... and if it doesn't you should get him back to fit the correct cable...


The invoice mentions altering the wiring in order to allow the fan timer to operate. The flex to the switch looks new.

There is no need to get him back, trying to make him out to be a cowboy just because you wouldn't do it like that is wrong. Would you go back to a job and rewire part of it just because the customer rings up months after you have finished and says "I've been on the internet and I have decided that you did it wrong"?

...

@Larches, there is nothing wrong with the wiring that is there. Just change the switch and get on with your life!


Yes I was trying to envisage how that conversation might play out (your last point is the more appealing prospect)!

:signthankspin:

 
But it's not a cpc

It's a green yellow core sleeved to be a switched live.

That's the arguement.

 
OK.....

For those with the BYB...... 411.3.1.1 - the last point applies IMHO.........


Another one of these 'open to interpretation' things there.

As I said earlier, I would class the flex as the appliance cord, and therefore it wouldn't need a CPC. You wouldn't run a CPC in to a double insulated light fitting that came with a length of flex fitted would you?

 
Another one of these 'open to interpretation' things there.

As I said earlier, I would class the flex as the appliance cord, and therefore it wouldn't need a CPC. You wouldn't run a CPC in to a double insulated light fitting that came with a length of flex fitted would you?


Not sure I agree "and at accessory"

Just how would you confirm R1 + R2 on a new install? You would always run a CPC to each accessory and if not required simply terminate it safely and available for future use...

Its yet again where the muppets who write the regs simply don't live in the real world..... it wouldn't take too much to clarify some of these points......

Just saying

 
May I throw in another comment, as I think the OP is again having difficulty separating REAL risks from technical compliance failures.

Assuming it is a 3 core flex, as it appears, and as the discussion supports, there is no increased fire risk, or of harm to a user of the facilities.

The risk, (and the reason for the much debated regulations), is that a future electrician is confused by the use of the apparent "earth" wire as a live conductor. Personally, I would like to think that any practicing electrician would be sufficiently worldly wise to avoid coming to harm here, especially as it must be evident  that it's a fan circuit.

The final, (as I see it), risk is that the non compliance with regulations leads to failure of some kind of future inspection or test, perhaps if you want to sell or rent the premises.

The over-riding consideration of course is that your fault diagnosis of a broken switch is correct. 

Fit your new switch and don't worry. There are far greater hazards in life than non-compliance with a regulation which even experts debate.

 
The risk, (and the reason for the much debated regulations), is that a future electrician is confused by the use of the apparent "earth" wire as a live conductor. Personally, I would like to think that any practicing electrician would be sufficiently worldly wise to avoid coming to harm here, especially as it must be evident  that it's a fan circuit.


Just a small observation on this whole debate, I don't think the risk is anything to do with future electricians doing any work, as you rightly point out, they should be competent and have enough noggin to suss out what functions all of the conductors are doing by looking at terminations or testing as needed. It is the DIY or untrained person who would potentially be at risk or confused. The proof of which is in the original question that started the whole topic off in the first place. From the original post:

I need to replace a pull cord switch for a shower extractor fan, but would appreciate advice regarding wiring as the old and new switches are different types. I'm attaching a picture of each.

The existing switch has common, L1 and L2, with the lives currently going together into COM and both neutrals terminated together - as can be seen in the photo.

The new switch is double pole and has "in" L & N and "out" L & N.

Can anyone confirm the correct config for the new switch please (and what's with the fan 'earth' to L2 on the existing switch)?


The quite natural assumption was that the green and yellow conductor even with a brown sleeve was an earth wire.  Personally I am not a fan of oversleeving a blue conductor in a light switch either, as we still get DIY questions where people naturally assume blue is a neutral not a switched live. It is all to easy for these sleeves to fall off when DIY accessory replacement is going on. Far better wherever possible to use twin brown or 4 core conductors for these sort of applications. Even with standard twin & earth at normal sockets and lights I have seen enough reverse polarity DIY wiring over the years. Keep things simple with correct colours will always help reduce this confusion. (and don't even mention central heating wiring with Blues, Yellows, Blacks, Greys, Green/Yellows all doing live functions!)

Doc H.   

 
The quite natural assumption was that the green and yellow conductor even with a brown sleeve was an earth wire.  Personally I am not a fan of oversleeving a blue conductor in a light switch either, as we still get DIY questions where people naturally assume blue is a neutral not a switched live


TBH, I have always said* the the sleeving is somewhat superfluous as the person in the switch will either ignore it (as in the case of the OP) or they will know that the wire in L2 is a switched live regardless of what colour it is.

*The exact phrase I have been known to use is "if you don't know that the blue wire in the other side of the switch to the brown is live then you shouldn't be in the switch in the first place".

 
TBH, I have always said* the the sleeving is somewhat superfluous as the person in the switch will either ignore it (as in the case of the OP) or they will know that the wire in L2 is a switched live regardless of what colour it is.

*The exact phrase I have been known to use is "if you don't know that the blue wire in the other side of the switch to the brown is live then you shouldn't be in the switch in the first place".


As a DIY-er, I wouldn't be suprised if sleeving gets overlooked by homeowners... in my case I'm not sure I spotted it first off, but did so later when I looked back at the picture I'd taken. Nonetheless I'd sussed out that the g/y wasn't being used as an earth, hence 'earth' in quotes. Had I thought about it some more, I would have realised what had been done, but it did throw me as it's not what you expect that wire to be used for (not wishing to fuel the argument either way, but agreed that it's not the ideal way of doing things).

 
Actually, in ireland brown/blue switch drops are outlawed. We use twin brown.

I can't remember the reg @Risteard will be able to quote it.
In the north they are permissible (as the work is carried out to BS7671) but it is never, ever done. Incidentally, BS7671 does specify a preference for conductors being identifiable throughout their length (though not a requirement so long as correctly marked at terminations).

In the south under ET101 (National Rules for Electrical Installations) the use of another colour marked at the terminations is expressly forbidden. As such all phase conductors must be coloured brown throughout their entire length. (In a three-phase installation single phase circuits can, however, be wired in phase colours. This is NOT permitted by BS7671.))

 
I remember never being allowed to use red/black in norn iron, always had to be twin red, and nihe specified big earth 1.5, ie, a 1.5 with a 1.5 earth. 
NIHE allow T&E so no problem with a reduced cpc. However they would still expect twin brown to be used for a switchdrop rather than remarking brown & blue (as would everyone here to be honest).

Also, they would expect 1.5mm^2 to be used for lighting. 1mm^2 isn't used here (and in fact is prohibited in the south for non-flexible cables).

Just to add, it is permissible now to remark green/yellow in a multicore cable for another purpose (athough many would consider it poor practice). I believe it may have been prohibited in earlier Editions of the Regulations. Obviously a cpc must still be terminated at each point in the wiring.

 
NIHE allow T&E so no problem with a reduced cpc. However they would still expect twin brown to be used for a switchdrop rather than remarking brown & blue (as would everyone here to be honest).

Also, they would expect 1.5mm^2 to be used for lighting. 1mm^2 isn't used here (and in fact is prohibited in the south for non-flexible cables).

Just to add, it is permissible now to remark green/yellow in a multicore cable for another purpose (athough many would consider it poor practice). I believe it may have been prohibited in earlier Editions of the Regulations. Obviously a cpc must still be terminated at each point in the wiring.
I'm going back 20+ years @Risteard we used to get special order 1.5 T&E with a 1.5 cpc incorporated, :eek:

Boy did we get bollxed if reels got mixed up and it was used on a private job, :shakehead

And yes, never ever seen 1mm anywhere, tbh,

3c&E was a novelty too,  only ever seen it in 3phase jobs, deffo not domestic, always had twin Strappers and single &E for L and SL from each switch. 

 
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