Wiring replacement pull cord switch

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er... if it fan has a timer (which i would assume for how its been wired) then that wiring method will stop the timer function from working...

L in brown & red

L out g/y sleeved brown

N in black & blue

a bit like a job a long time ago where the architect insisted on DP switching for the lights and refused to listen to why it should be SP, then finally agree'd to SP after the job was complete and pointed out that the emergency lights come on every time you turn the light switch off...
Shoot!  Your absolutely right. I put the neutrals on the switch so the neon would work, but neutral is needed all the time!  Apologies 

 
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Hang on, I'm lost here, theres a reg there that states "Green+yellow shall be used exclusively for identification of a protective conductor, and this combination shall not be used for any other purpose." Next bit says it shall not be oversleeved at its terminations.

So whoever has wired that switch/fan has used green/yellow as a live conductor, and oversleeved it, yet you say theres nothing in the regs to say not to do so?

I'm not seeing your logic.
It says 

Single core cables 

We're using a multi core here,

Ambiguous,? :C

 
I feel a little sorry for the original poster who must be quite bewildered by the discussion he has triggered.  What he has there may be incorrect to regs but in my opinion isn't actually unsafe. 

 
I take issue with that. Using the CPC as the switched live IS unsafe, it is an un  insulated cable with just the sheath to protect it.

It would be a bit less unsafe, if the CPC had been used as a substitute neutral, brown for permanent L and blue for switched L.

the fact that it's a brown / blue to the fan suggests it's a recent cable and also implies it is quite likely that it won't be to hard to replace it with a 3 core & E to do the job properly.

 

 
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I take issue with that. Using the CPC as the switched live IS unsafe, it is an un  insulated cable with just the sheath to protect it.

It would be a bit less unsafe, if the CPC had been used as a substitute neutral, brown for permanent L and blue for switched L.

the fact that it's a brown / blue to the fan suggests it's a recent cable and also implies it is quite likely that it won't be to hard to replace it with a 3 core & E to do the job properly.

 


if it was T&E, then yes. but its flex. the insulation is the same as the L&N

 
And what zone would that be ?

As long as the fan is ip4x(which most are) and RCD protected why waste money on a 12v fan


I would imagine you would call it Zone1 ??? :C

701.55 specifically states that equipment should be suitable for Zone 1 ref the manufactures instructions  (pg 208 bottom quarter)

Take a typical 230v IP44 bathroom extractor fan such as http://www.screwfix.com/p/manrose-mg100t-20w-gold-standard-axial-bathroom-extractor-fan-w-timer/62530#product_additional_details_container

Ceiling or wall mounted item...

The instructions http://www.free-instruction-manuals.com/pdf/pa_474957.pdf   specifically say:-

fan instructions.JPG

Which to me doesn't say bang it anywhere with an RCD as its IP44...

and as Zone1 is the vertical bit up above the bath or shower that's the Zone where is shouldn't be at a guess?

So as I said earlier it is possible that the OP's fan is not suitable for its installed location anyway! 

Agreed NOT ALL manufactures fans may have the same installation instructions... But I have seen enough over the years that do, hence my earlier comment..

And at the end of the day when giving advice to DIY'ers on an open public forum I would tend to be cautious about what we who are supposedly the knowledgeable ones,

say can and can't be done in a safe and/or compliant manner with ref to current regs.

If IP4x was all that was needed I doubt manufacturers would bother making 12v fans either!

:popcorn  

 
if it was T&E, then yes. but its flex. the insulation is the same as the L&N
I must admit, from the original picture I thought it was t&e with a green / yellow sleeve on the CPC and then a brown sleeve over.

I should have gone to (insert name of your preferred optician)

I still maintain, if you are going to use green / yellow as anything other than a CPC, then using it as the neutral would be less dangerous.

 

 
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I would imagine you would call it Zone1 ??? :C

701.55 specifically states that equipment should be suitable for Zone 1 ref the manufactures instructions  (pg 208 bottom quarter)

Take a typical 230v IP44 bathroom extractor fan such as http://www.screwfix.com/p/manrose-mg100t-20w-gold-standard-axial-bathroom-extractor-fan-w-timer/62530#product_additional_details_container

Ceiling or wall mounted item...

The instructions http://www.free-instruction-manuals.com/pdf/pa_474957.pdf   specifically say:-

View attachment 7827

Which to me doesn't say bang it anywhere with an RCD as its IP44...

and as Zone1 is the vertical bit up above the bath or shower that's the Zone where is shouldn't be at a guess?

So as I said earlier it is possible that the OP's fan is not suitable for its installed location anyway! 

Agreed NOT ALL manufactures fans may have the same installation instructions... But I have seen enough over the years that do, hence my earlier comment..

And at the end of the day when giving advice to DIY'ers on an open public forum I would tend to be cautious about what we who are supposedly the knowledgeable ones,

say can and can't be done in a safe and/or compliant manner with ref to current regs.

If IP4x was all that was needed I doubt manufacturers would bother making 12v fans either!

:popcorn  
You are correct I was quoting reg 701.512.2

I'm aware of reg 701.55 but forgot the last bit (according to manufacture instructions).

Something I need to check more regular

 
I actually think the majority of you are missing the point of the context of 514.4.2...

The opening sentence refers specifically to Green/Yellow conductor identification and its says it shall be used EXCLUSIVLEY for a protective conductors and NO other purpose.

If oversleeving as a Live was an acceptable practice then this would not be worded as it is.

The only exception is the second paragraph which relates to 514.4.3 which in itself refers to PEN conductors..

(combined neutral and earth)...

which can be either..  Green/Yellow over-sleeved Blue..

OR

Blue over-sleeved Green/Yellow....

so.. our fan is NOT utilising a PEN conductor therefore the Green/Yellow should be exclusively as a CPC..

NOT a switched Live.

Flex can be used as fixed wiring (assuming it has the correct current capacity appropriate for the protective device fitted)

and three core plus earth, (cable or flex), is unbelievably simple to obtain...

So how hard can it be to just do the job right in the first place?

Too much time wasted about how you can bend the guidance so that a CPC can become a Live conductor.

:popcorn

The chances are this original wiring was either a DIY or Builder or Bathroom fitter by the cable selected...

so its not beyond the realms of possibility that other bits are wrong as well.

:C

 
I actually think the majority of you are missing the point of the context of 514.4.2...

The opening sentence refers specifically to Green/Yellow conductor identification and its says it shall be used EXCLUSIVLEY for a protective conductors and NO other purpose.

If oversleeving as a Live was an acceptable practice then this would not be worded as it is.

The only exception is the second paragraph which relates to 514.4.3 which in itself refers to PEN conductors..

(combined neutral and earth)...

which can be either..  Green/Yellow over-sleeved Blue..

OR

Blue over-sleeved Green/Yellow....

so.. our fan is NOT utilising a PEN conductor therefore the Green/Yellow should be exclusively as a CPC..

NOT a switched Live.

Flex can be used as fixed wiring (assuming it has the correct current capacity appropriate for the protective device fitted)

and three core plus earth, (cable or flex), is unbelievably simple to obtain...

So how hard can it be to just do the job right in the first place?

Too much time wasted about how you can bend the guidance so that a CPC can become a Live conductor.

:popcorn

The chances are this original wiring was either a DIY or Builder or Bathroom fitter by the cable selected...

so its not beyond the realms of possibility that other bits are wrong as well.

:C
I disagree

I think you are interpreting the reg as in,

Everyone else is wrong if they don't agree with how I interpret it

You cannot take any one reg in isolation

Show the reg where it definitively States under no circumstance may a green/yellow coloured cable be used as anything but a cpc, 

I've still got this virtual beer on offer,  Guinness

 
According to 514.4.2

As long as the sleeving covers a minimum of 70% of the exposed G/Y then its perfectly acceptable in a multi core cable, or, if it only covers 10% then the markings for a cpc have not been met, there are now 3 colourings, 

Either way, its now not marked as a cpc, 70/30 % split, :C

2nd paragraph explicitly states

Single core conductor 

No mention of multi core cable whatsoever

 
I feel a little sorry for the original poster who must be quite bewildered by the discussion he has triggered.  What he has there may be incorrect to regs but in my opinion isn't actually unsafe. May I suggest that the following is helpful.

Lin  =  Red + Brown 

Nin =  Black

Lout = The sleeved green core of the flex

Nout = Blue

 Terminate the incoming (unused) earth core in the terminal provided in the new box, just as it was in the old.

As regards opening up the knockouts, if they are tough to pierce start with a small drill and open up with a file. As  space appears tight in the new switch it will probably be best to separate the incoming and outgoing cables and use both knockouts. Shorten the wires to lay neatly, with the cable sheaths finishing just inside the box. (i.e. do not just push spare wire back up into the void.)


er... if it fan has a timer (which i would assume for how its been wired) then that wiring method will stop the timer function from working...

L in brown & red

L out g/y sleeved brown

N in black & blue

a bit like a job a long time ago where the architect insisted on DP switching for the lights and refused to listen to why it should be SP, then finally agree'd to SP after the job was complete and pointed out that the emergency lights come on every time you turn the light switch off...

Thanks everyone for all your responses... especially Geoff1946 who rightly predicted that I'd be a bit bewildered by what we can call the 3 Core Controversy, and kindly addressed my main query, and also Andy(tm) for the correction to that advice.

To answer a few questions...

  • The extractor fan was installed earlier this year, replacing one that had failed.
  • The old one had no overrun/timer feature but the new one does, and I'd prefer to keep using that feature if possible.
  • It was replaced by a Part P & NICEIC registered electrician.
  • I'm fairly sure he said he'd had to replace the flex from the old fan for some reason (and it does look new).
  • The switch is located well away from the shower, next to the door (outside Zones 1/2 as I understand it).
  • The fan unit is installed in the loft (attached to a joist).
So on this thorny question of the earth/CPC used as switched live, I understand there's a regulatory and 'best practice' debate here at the very least, but can anyone elaborate on the practical repercussions of doing it this way, so I know how much of a risk I've ended up with here?

 
 so I know how much of a risk I've ended up with here?


well whether it complies with regs or not is debatable (as you have already noticed, we have a great set of regulations that can be read many ways and end up with many different opinions). personally, i would have used a 4 core cable if it was a new install, although if it was just a swap an existing fan leave it as is

its not dangerous and its not likely to electrocute someone or cause a fire etc

 
well whether it complies with regs or not is debatable (as you have already noticed, we have a great set of regulations that can be read many ways and end up with many different opinions). personally, i would have used a 4 core cable if it was a new install, although if it was just a swap an existing fan leave it as is

its not dangerous and its not likely to electrocute someone or cause a fire etc


Thank you, that's definitely good to know.

 
Thanks everyone for all your responses... especially Geoff1946 who rightly predicted that I'd be a bit bewildered by what we can call the 3 Core Controversy, and kindly addressed my main query, and also Andy(tm) for the correction to that advice.

To answer a few questions...

  • The extractor fan was installed earlier this year, replacing one that had failed.
  • The old one had no overrun/timer feature but the new one does, and I'd prefer to keep using that feature if possible.
  • It was replaced by a Part P & NICEIC registered electrician.
  • I'm fairly sure he said he'd had to replace the flex from the old fan for some reason (and it does look new).
  • The switch is located well away from the shower, next to the door (outside Zones 1/2 as I understand it).
  • The fan unit is installed in the loft (attached to a joist).
So on this thorny question of the earth/CPC used as switched live, I understand there's a regulatory and 'best practice' debate here at the very least, but can anyone elaborate on the practical repercussions of doing it this way, so I know how much of a risk I've ended up with here?
It is perfectly acceptable within both the regs and from a legal viewpoint to use the green and yellow coloured wire within a flexible cable for any purpose you wish provided it is so marked at each end.

Anyone wishing to argue otherwise clearly doesn't understand the exclusions and exceptions and exclusivity of the regulation they are so fond of quoting,

That's a common misconception with people that read things and think they understand the theory, but don't understand how to implement them in practice. 

Any COMPETENT electrician understands this,

Remember, just because you are on an electricians forum, it doesn't mean everyone here is COMPETENT beyond reading a book, (and perhaps misunderstanding said book.)

 
Thanks everyone for all your responses... especially Geoff1946 who rightly predicted that I'd be a bit bewildered by what we can call the 3 Core Controversy, and kindly addressed my main query, and also Andy(tm) for the correction to that advice.

To answer a few questions...

  • The extractor fan was installed earlier this year, replacing one that had failed.
  • The old one had no overrun/timer feature but the new one does, and I'd prefer to keep using that feature if possible.
  • It was replaced by a Part P & NICEIC registered electrician.
  • I'm fairly sure he said he'd had to replace the flex from the old fan for some reason (and it does look new).
  • The switch is located well away from the shower, next to the door (outside Zones 1/2 as I understand it).
  • The fan unit is installed in the loft (attached to a joist).
So on this thorny question of the earth/CPC used as switched live, I understand there's a regulatory and 'best practice' debate here at the very least, but can anyone elaborate on the practical repercussions of doing it this way, so I know how much of a risk I've ended up with here?
If it was an INCEIC and Part P electrician that did it, I would have expected him to have used a bit of 3 core & earth or 4 core flex. While it might be technically okay to use the 3 core flex I would only have done that if it was an existing flex plastered into the wall and would have messed up the bathroom to replace it.

As the fan is in the loft (in line fan) and it's a ceiling switch, I would replace that cable.

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?

 

 
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Thanks everyone for all your responses... especially Geoff1946 who rightly predicted that I'd be a bit bewildered by what we can call the 3 Core Controversy, and kindly addressed my main query, and also Andy(tm) for the correction to that advice.

To answer a few questions...

  • The extractor fan was installed earlier this year, replacing one that had failed.
  • The old one had no overrun/timer feature but the new one does, and I'd prefer to keep using that feature if possible.
  • I'm fairly sure he said he'd had to replace the flex from the old fan for some reason (and it does look new)
So on this thorny question of the earth/CPC used as switched live, I understand there's a regulatory and 'best practice' debate here at the very least, but can anyone elaborate on the practical repercussions of doing it this way, so I know how much of a risk I've ended up with here?


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...

 
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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"?

Of course you wouldn't. I have still yet to see anyone clearly define where it says this is wrong. I have only seen articles saying it is acceptable. If someone comes on here and posts an EICR everyone says "you can't arbitrarily decide that something is wrong without citing a regulation to back it up, he's an idiot/cowboy etc", which is exactly what is happening here.

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

 

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