Can anyone help with my bathroom light pull chord switch?

[Bgy333]

I’ve got my P16th edition papers in 2006 so not a total beginner (I’m plumber as my trade tbh) but this pull chord bathroom light is not working and if trips the consumer unit .

Basically the old switch broke so I took a photo of the wiring before fitting a new light.

And it doesn’t work.

The brown an red wires are live and the two connect together are live too. I test them with this blue pen tester .

I’m gonna include photos of everything so any help be great thx

 

[Avo Mk8]

What I would expect at the pull cord position is that the switch would have been between the red and brown wires, the two earth cores properly sleeved and connected to the switch earth terminal (if there is one), and the black and blue wires connected together by a wago or terminal block isolated from everything else.
Then at the light fitting, traditional connections of L, N and E.
Is this how you have tried wiring it?
Your old switch is two way, but it looks like only the two screws on the left side (third photo) have been used- I'm assuming there aren't enough wires for a two way circuit. Is there another switch for this circuit?

Tidying up of wire lengths and sleeving needed!

The above rather rashly assumes wire colours have been used for their traditional purposes.

Also be wary of quirks of pen tester.

 

[Bgy333]

What I would expect at the pull cord position is that the switch would have been between the red and brown wires, the two earth cores properly sleeved and connected to the switch earth terminal (if there is one), and the black and blue wires connected together by a wago or terminal block isolated from everything else.
Then at the light fitting, traditional connections of L, N and E.
Is this how you have tried wiring it?

Tidying up of wire lengths and sleeving needed!

The above rather rashly assumes wire colours have been used for their traditional purposes.

Be wary of quirks of pen tester.

Thanks for replying so fast but that’s what I did the red in common, brown L1, then the Earths to to E box (u can see where it’s been scorched)

I’ve got a traditional multi meter and so which wires would I test with Red and Black pls?

I thought the pen test was a bit crap when the Earth cable would beep the pen after a few secs!

Thsnks in. Advance (if u reply)….!

 

[Avo Mk8]

Thanks for replying so fast but that’s what I did the red in common, brown L1, then the Earths to to E box (u can see where it’s been scorched)

I’ve got a traditional multi meter and so which wires would I test with Red and Black pls?

I thought the pen test was a bit crap when the Earth cable would beep the pen after a few secs!

Thsnks in. Advance (if u reply)….!

In your movie the black wire looks nicked - did it get trapped somehow? That bit needs cutting off if you have enough cable length.
Firstly what trips in the consumer unit - MCB or RCD or what?

What are the wire colours at the light fitting? (black/red, or blue/brown) - I mean the wire coming out of the ceiling.
If the new fitting is up, with power off you could disconnect switch and check for any short circuit (between L-E or L-N etc)

Sounds like your earth core may not be connected, or with all this bare conductor about, has got trapped and connected to something it shouldn't!

 

[Bgy333]

In your movie the black wire looks nicked - did it get trapped somehow? That bit needs cutting off if you have enough cable length.
Firstly what trips in the consumer unit - MCB or RCD or what?

What are the wire colours at the light fitting? (black/red, or blue/brown) - I mean the wire coming out of the ceiling.
If the new fitting is up, with power off you could disconnect switch and check for any short circuit (between L-E or L-N etc)

Sounds like your earth core may not be connected, or with all this bare conductor about, has got trapped and connected to something it shouldn't!

I’ll take some more photos and post them now

 

[Bgy333]

more photos
The trip switch is first one on the left

 

[Avo Mk8]

OK
So I'm sorry but I don't understand what I'm looking at in the multitude of photo's.
The last ceiling fitting in your first post, is not the same as the last photo in the second post of photos (post #6)?
Do you have two seperate ceiling fittings?
The last photo in the #6 post shows two red wires in the ceiling rose. where has that second red wire come from and go to?
I don't see two red wires in any of the other photo's!
Tell me the setup Please!

So it's the MCB on the left of the CU that trips, not the RCB on the very right?
I guess that means you have some sort of short circuit between L & N on this circuit

 

[Bgy333]

OK
So I'm sorry but I don't understand what I'm looking at in the multitude of photo's.
The last ceiling fitting in your first post, is not the same as the last photo in the second post of photos (post #6)?
Do you have two seperate ceiling fittings?
The last photo in the #6 post shows two red wires in the ceiling rose. where has that second red wire come from and go to?
I don't see two red wires in any of the other photo's!
Tell me the setup Please!

So it's the MCB on the left of the CU that trips, not the RCB on the very right?
I guess that means you have some sort of short circuit between L & N on this circuit

OK
So I'm sorry but I don't understand what I'm looking at in the multitude of photo's.
The last ceiling fitting in your first post, is not the same as the last photo in the second post of photos (post #6)?
Do you have two seperate ceiling fittings?
The last photo in the #6 post shows two red wires in the ceiling rose. where has that second red wire come from and go to?
I don't see two red wires in any of the other photo's!
Tell me the setup Please!

So it's the MCB on the left of the CU that trips, not the RCB on the very right?
I guess that means you have some sort of short circuit between L & N on this circuit

I’ve pulled the wires down and cut little bit grey sheathing off.

The other pictures are the light fittings where the wires connect to the lights themselves.

Then a picture of the consumer unit

Hope this helps!

 

[Avo Mk8]

I’ve pulled the wires down and cut little bit grey sheathing off.

The other pictures are the light fittings where the wires connect to the lights themselves.

Then a picture of the consumer unit

Hope this helps!

Just to clarify - there are two light fittings as well as the switch?
Have you already rewired the ceiling rose shown in the last photo (I mean the photo with the close up of the metal bar), with the two red wires in it?
Presumably you have two red, two black, and two earth feeding that light?

 

[Bgy333]

Just to clarify - there are two light fittings as well as the switch?
Have you already rewired the ceiling rose shown in the last photo (I mean the photo with the close up of the metal bar), with the two red wires in it?
Presumably you have two red, two black, and two earth feeding that light?

That’s a yes to 2 light fixtures

1st one

2 black
2 red
2 earth

2nd one

1black
1ted
1 earth

 

[Avo Mk8]

That’s a yes to 2 light fixtures

1st one

2 black
2 red
2 earth

2nd one

1black
1ted
1 earth

What I would check first, with power off, is disconnect the red and black at the switch, and with no bulbs in the light fittings, use the multimeter on ohms range, check there is infinite resistance (ie open cicuit) between black and red. Not ideal, but at least would rule out a direct short in this section. Have you done any simple continuity checks to see if any miss connections?

I'm not clear if you have the new lights installed, or if wires are still hanging from the ceiling? Are new lights now in place, or are cables still disconnected?

 

[Avo Mk8]

Please could you explain the series of events that lead to the breaker tripping?
Did it trip when you first turned the power back on after wiring the lights,
or did you switch the power on, nothing happened, then you pulled the switch cord, and the breaker tripped?
If the second, the pull switch might now be welded permanently on!

Normally one would expect to test a circuit before applying power to it, though that doesn't seem to be the DIY way!

 

[Bgy333]

What I would check first, with power off, is disconnect the red and black at the switch, and with no bulbs in the light fittings, use the multimeter on ohms range, check there is infinite resistance (ie open cicuit) between black and red. Not ideal, but at least would rule out a direct short in this section. Have you done any simple continuity checks to see if any miss connections?

I'm not clear if you have the new lights installed, or if wires are still hanging from the ceiling? Are new lights now in place, or are cables still disconnected?

The lights were installed before (by me) and worked fine, it’s when the old switch was faulty and I’ve gone to install the new one I’ve had problems of it tripping out. I just took a photo of the old wiring and copied it to the new switch

 

[Avo Mk8]

The lights were installed before (by me) and worked fine, it’s when the old switch was faulty and I’ve gone to install the new one I’ve had problems of it tripping out. I just took a photo of the old wiring and copied it to the new switch

OK I understand better, thanks.
It seems obvious to concentrate on there being something wrong in or around the new switch.
The way you've described wiring it is how I would have done it!

Do the lights work all of the time, and the mcb trips only sometimes, or how does the tripping manifest itself?

 

[davesparks]

What was wrong with the old switch? Could it have been the fault making the old switch appear to be faulty when it actually isn't?

 

[Bgy333]

OK I understand better, thanks.
It seems obvious to concentrate on there being something wrong in or around the new switch.
The way you've described wiring it is how I would have done it!

Do the lights work all of the time, and the mcb trips only sometimes, or how does the tripping manifest itself?

As it is now ( or was when wired as everyone including me assumed was the correct way) it would work for a bit then trip out, I’ve decorated since the dodgy switch started being dodgy and as a typical tradesmen the wife keeps reminding me every f’n year to sort it it and this year seems the year ! So basically recently the lights have been removed and wires hanging down ( it’s fine it’s adults only house!) and the string tied up . When some one not familiar with it would pull the cord it would trip and you have to pull again otherwise it would constantly trip.

 

[Bgy333]

Tbh it could possibly have been the wiring but I just assumed the switch was broken so replaced it but just coped with no bathroom light for about 4 years lol

 

[Avo Mk8]

As it is now ( or was when wired as everyone including me assumed was the correct way) it would work for a bit then trip out, I’ve decorated since the dodgy switch started being dodgy and as a typical tradesmen the wife keeps reminding me every f’n year to sort it it and this year seems the year ! So basically recently the lights have been removed and wires hanging down ( it’s fine it’s adults only house!) and the string tied up . When some one not familiar with it would pull the cord it would trip and you have to pull again otherwise it would constantly trip.

Well from everything you've said it seems there has been, and still is, a long standing fault, where if the switch was on, the MCB would trip. That implies somewhere between the light switch and the last light fitting, there is a problem with the wiring. The fact that an MCB trips and not the RCD (assuming the latter works - have you tried the test button recently?) implies to me a more serious problem.
I think either you should get a professional in with a multifunction tester to investigate, or as a minimum, replace the cables in the ceiling with new, all the way from the switch to the first light and then to the second light.

 

[Avo Mk8]

What was wrong with the old switch? Could it have been the fault making the old switch appear to be faulty when it actually isn't?

Sounds like you're right!

 

[Bgy333]

I’ve just got my multi meter in the wires in the loft the blue and brown is showing no reading and the read and black a tiny one I’ll include a pic and show the settings on my multi meter, obv the wires are all dangling so if I’m supposed to be connecting 2 lives I’m not. Cos ones not live and the other minimal

 

[Bgy333]

photo of the wiring in the loft it leads to this switch

 

[Bgy333]

So maybe this is where the issue is as there’s only one live wire here and I’m assuming there were 2 lives needed connecting, maybe the switch was being used as some kind of junction box and the switch was thswitch?

The switch isn’t in the bathroom and obv that wiring is new , I’ve discounted that switch as nothing as it “didn’t work”, it’s in a room connecected onto the bathroom by a door and this room was knocked into one massive bedroom before we moved in. I redid the partition and that switch never worked and so that’s where my problem maybe?

 

[Bgy333]

Whwre the switch is near the door into the bathroom

 

[Avo Mk8]

photo of the wiring in the loft it leads to this switch

I'm trying to make sense of those first two pics. This seems to be the problem.
the metal clad switch with the red, yellow, blue wires coming out of it seems to be a two way switch to operate the bathroom light in conjunction with the pull cord.
If the brown and blue wires leading off to the left go to your pull cord, then the old (broke) pull cord switch was being used two way. The bare copper earth wire is being used as the common live.
So it's not an earth wire at all!
If you want to continue to use that metal switch in pic 2, then that bit of brown/blue cable in pic 1 needs repacing with 3 core to the light switch. I think the problems you have been having are all because the earth wire is being used as a live wire, and now that is a problem at the new pull switch.
Is your new pull switch 2 way?
Can you replace the 2 core cable with 3 core without too much difficulty?

getting somewhere now !

 

[Avo Mk8]

I’ve just got my multi meter in the wires in the loft the blue and brown is showing no reading and the read and black a tiny one I’ll include a pic and show the settings on my multi meter, obv the wires are all dangling so if I’m supposed to be connecting 2 lives I’m not. Cos ones not live and the other minimal

In addition to the other recent discoveries, the leakage across red and black just using a multimeter is a bad sign.
You need an insulation resistance tester to check the resistance at 500V. Have you got a friendly sparky who could do that for you?

 

[Bgy333]

I'm trying to make sense of those first two pics. This seems to be the problem.
the metal clad switch with the red, yellow, blue wires coming out of it seems to be a two way switch to operate the bathroom light in conjunction with the pull cord.
If the brown and blue wires leading off to the left go to your pull cord, then the old (broke) pull cord switch was being used two way. The bare copper earth wire is being used as the common live.
So it's not an earth wire at all!
If you want to continue to use that metal switch in pic 2, then that bit of brown/blue cable in pic 1 needs repacing with 3 core to the light switch. I think the problems you have been having are all because the earth wire is being used as a live wire, and now that is a problem at the new pull switch.
Is your new pull switch 2 way?
Can you replace the 2 core cable with 3 core without too much difficulty?

getting somewhere now !

Like I said in original post I did my P16th papers (20 odd years ago like) so not up to date but yes replacing 2 core to 3 core no problem but I’ve no issues not using the light switch on the wall and just the pull cord.

When I was testing the wires one the earths was showing live and someone comments don’t trust pen testers!

I’m able to do whatever I just don’t know where to put which wires - one of the earths is scorched so maybe that’s the live one!

 

[Bgy333]

In addition to the other recent discoveries, the leakage across red and black just using a multimeter is a bad sign.
You need an insulation resistance tester to check the resistance at 500V. Have you got a friendly sparky who could do that for you?

I’ve got this if you tell me how to set it or what to do?

So basically forget the silver switch how would I connect just my pull cord to work the lights ! I can access the wires. In the loft to do any messing up there is not an issue!

 

[Avo Mk8]

Like I said in original post I did my P16th papers (20 odd years ago like) so not up to date but yes replacing 2 core to 3 core no problem but I’ve no issues not using the light switch on the wall and just the pull cord.

When I was testing the wires one the earths was showing live and someone comments don’t trust pen testers!

I’m able to do whatever I just don’t know where to put which wires - one of the earths is scorched so maybe that’s the live one!

So

I’ve got this if you tell me how to set it or what to do?

So basically forget the silver switch how would I connect just my pull cord to work the lights ! I can access the wires. In the loft to do any messing up there is not an issue!

The problem is a multimeter won't stress the cable with a high enough voltage to do a proper test. My concern is the old black/red section of cable might have be a problem, but putting that aside, there's the correct connection of the pull cord to sort out first.

 

[Bgy333]

So

The problem is a multimeter won't stress the cable with a high enough voltage to do a proper test. My concern is the old black/red section of cable might have be a problem, but putting that aside, there's the correct connection of the pull cord to sort out first.

That’d be sound pls do you want me to test the “earth / live “ see what that shows?

 

[Bgy333]

The red and earth is showing live on my pen tester but I don’t know how to test how much current on the earth wire like I say it shows minimal on the multi meter

 

[Avo Mk8]

Like I said in original post I did my P16th papers (20 odd years ago like) so not up to date but yes replacing 2 core to 3 core no problem but I’ve no issues not using the light switch on the wall and just the pull cord.

When I was testing the wires one the earths was showing live and someone comments don’t trust pen testers!

I’m able to do whatever I just don’t know where to put which wires - one of the earths is scorched so maybe that’s the live one!

I said don't trust pen testers, but ironically in this instance it was telling you the live earth wire was live!
It needs to be established if there is a permanent live at the pull cord that is not coming from the wall switch.

 

[Avo Mk8]

The red and earth is showing live on my pen tester but I don’t know how to test how much current on the earth wire like I say it shows minimal on the multi meter

It's not obvious to me where live is coming from!
Why are the blue and black wires connected together by the choc block? Were they together like that in the old pull cord?
Or did you put them together because that seems right colour wise?
The reason I ask is that I can't make sense of this wiring yet!

 

[davesparks]

I think it's time to suggest you call an electrician, you have some dangerous wiring there that needs sorting out.
Exposed connector blocks and the earth core of a T&E cable connected to live are not, and have never been, acceptable.

 

[Bgy333]

It's not obvious to me where live is coming from!
Why are the blue and black wires connected together by the choc block? Were they together like that in the old pull cord?
Or did you put them together because that seems right colour wise?
The reason I ask is that I can't make sense of this wiring yet!

I copied the old wiring i believe- they were always like that it’s possible- seems probable that I’ve done it wrong, maybe the red and brown should have gone one side of the pull cord switch and the live earth the other? That’s the only way 2 lives would connect on the switch ?

 

[brianmoooore]

I think it's time to suggest you call an electrician, you have some dangerous wiring there that needs sorting out.
Exposed connector blocks and the earth core of a T&E cable connected to live are not, and have never been, acceptable.

This!

 

[Avo Mk8]

I copied the old wiring i believe- they were always like that it’s possible- seems probable that I’ve done it wrong, maybe the red and brown should have gone one side of the pull cord switch and the live earth the other? That’s the only way 2 lives would connect on the switch ?

Let me have a think about this. I'm off for a few hours. I'll get back to you.
Are you able to check, safely, what if anything is live?

 

[Bgy333]

Like said I did my P16th edition papers 2007 so checking live wires besides feeling it they’re warm lol isn’t a problem I’ve got the two multi meter shown and the pen tester

 

[Avo Mk8]

I don't think it is possible to determine remotely exactly how your circuit was wired just from the photo's.
The original configuration might have been something like that shown below. That is just illustrative - I don't know which terminal is which on the wall switch.
And as has been said, the use of the bare earth wire as a live connection is unacceptable, and has caused you difficulties in trying to replace the switch.
Your experience previously as an electrician ought to allow you to work out how to correctly connect what you have.

However, the fact that you see a deflection on the needle of your multimeter, set to ohms range, when checking between L and N on the old cable between the lights (otherwise disconnected) leads me to join others here who have recommended getting an electrician in.

This forum is not supposed to give step by step guidance. I think I've gone as far as I possibly can to try and help, so it's over to you now to do the responsible thing and get this wired properly and made safe.

 

[Bgy333]

I don't think it is possible to determine remotely exactly how your circuit was wired just from the photo's.
The original configuration might have been something like that shown below. That is just illustrative - I don't know which terminal is which on the wall switch.
And as has been said, the use of the bare earth wire as a live connection is unacceptable, and has caused you difficulties in trying to replace the switch.
Your experience previously as an electrician ought to allow you to work out how to correctly connect what you have.

However, the fact that you see a deflection on the needle of your multimeter, set to ohms range, when checking between L and N on the old cable between the lights (otherwise disconnected) leads me to join others here who have recommended getting an electrician in.

This forum is not supposed to give step by step guidance. I think I've gone as far as I possibly can to try and help, so it's over to you now to do the responsible thing and get this wired properly and made safe.

View attachment 102624

You’ve been fantastic and don’t worry I know that sometimes the saying no good deed comes into play and I’ve had it myself tbh “well you told me……..” etc etc

See o fitted the bathroom and as part of it fitted new lights. So it was working fine, I never used the switch on the wall ever.

So thinking back I believe I bought a new silver plastic pull cord switch for the bathroom , and then it never worked since .

I would’ve thought that sleeved green / yellow going into com1 etc on the switch as wrong and connecting them together as normal, dismissing the original photo I had and then had this issue since

 

[UNG]

Looking through all the pictures and posts if the switch outside the bathroom is not needed then just lose the brown / blue T&E at the pull switch and it then looks like you are left with a live, switch live and an earth from the light fitting position in the remaining T&E