New light(s) installation problems

[Advocate]

Hi everyone,

This looked like a nice friendly helpful place to post my question

My missus recently insisted we buy two new light fittings for the hall and landing, and I fitted them myself. That was a mistake. Now I can't get all the lights on that circuit to work

This circuit goes to a lights in the hall, landing, bedroom, study, lounge and kitchen.

The hall has a double switch (one for the hall and one for the landing), the landing has a single switch (just for the landing light), the bedroom has a single switch, the lounge has two switches for the one light, the kitchen has one switch and the study has two lights, each on their own switch. I hope that makes sense.

Coming from the ceiling in the hall I have 3 black wires, 4 red wires and 4 earth wires. The way I initially wired them (and was well chuffed with myself as both the hall and landing lights worked) resulted in both study lights only coming on very dim but the hall light would come on whenever I switched either study light on.

So today, armed with a diagram from another website I tried some trial and error to get the damn thing working properly. The diagram said I should have the switched live connected to the brown wire from the light (which it is), three of the red wires together, and the two other black wires to the blue on the light (which they are).

Now, it doesn't matter which red wire I connect up to the switched live I can't get all of my lights to work. One or more of them don't work with each combination, with one of them resulting in the trip switch going.

I'm at the end of my tether, any ideas? Would the wiring of the landing light interfere with the downstairs lights? Could I have the switched live wrong? (But wouldn't the trip switch then pop if the switched live was connected to another black wire?)

Thanks in advance folks

Alistair
_______________________
moderator

please note 5 your title has been edited

 

[Advocate]

From reading posts in this forum this is what I can gather so far.

Of the three black leads one comes from the switch wire, I have confirmed which one is the switch wire and that is indeed the one I have connected to the live brown wire of the light.

The other two black leads should be connected to the neutral wire of the light, which they are.

If I had three red leads they should all be connected together, unfortunately I have 4. If I connect all 4 together then I have problems, if I connect any of the three reds that DON'T come from the switch wire to the black from the switch wire I have problems.

I'm really really stumped here.

As a side note, I removed the two gang switch from the wall in the hall and one of the red wires wasn't connected. Thinking that may have been the problem I reconnected it but still no joy.

Could one of these red wires be supposed to go to the neutral???

When I took the original light fitting down there was a red wire connected to a black wire (which I think was the switch wire but this was so long ago I can't remember).

Anybody? Please?

 

[securespark]

Check your connections!

See the For Reference Sticky at the top of the list.

You need to be able to identify all the conductors: permanent live feed in, out and to the switch, the switched live to the fitting, and neutral and earth conductors.

Also, have you altered any of the connections at the switches?

In a regular ceiling rose in the loop-in system, you will find three lives connected to each other but to nothing else, and a switched live and two neutrals connected to the fitting, along with an earth.

 

[Advocate]

Check your connections!

See the For Reference Sticky at the top of the list.

You need to be able to identify all the conductors: permanent live feed in, out and to the switch, the switched live to the fitting, and neutral and earth conductors.

Also, have you altered any of the connections at the switches?

In a regular ceiling rose in the loop-in system, you will find three lives connected to each other but to nothing else, and a switched live and two neutrals connected to the fitting, along with an earth.

I haven't altered any of the connections at the switches. The switch that I removed from the wall is a two gang switch (one for the hall and one for the landing) and has (on the hall side of the switch) a black wire at the top and a red wire at the bottom with another small piece of red wire going from the hall switch to the landing switch. The landing switch then has another red wire leading in the bottom(or out? who knows) and a black and red wire at the top.

Although I understand the principle of the 3 wires (in, switch, out) it is vexing me how I have a 4th wire that only has a red and earth wire (no black). Hmmm just had a second look at that switch and the red wire at the bottom of the landing side of the switch (this is getting confusing) has a red wire and an earth while the others have a red and black.

/me is even more confused.

 

[Advocate]

I've drawn a couple of diagrams, hope they help explain things better.

The first is of the downstairs light switch

and the second is of the wires from the ceiling....hope this sheds some light on things.

Thanks for your help btw

 

[mapj1]

Your understanding is correct, but clearly there is some confusion as to which wire is going where.
The link between the two switches downstairs is significant. It means the unswitched live feed is shared between the two circuits, and is on that link.

You really need a meter or at least (step back from flames of protest) one of those neon screwdriver things that would allow you to identify the feed-in wires and allow them to be separated from the outgoing supply on to later things in the chain.

The lights at half mast occurs when you put the lights further down the chain where the switch ought to be, and they end up in series.
The blown trip occurs when the switch is placed across incoming supply and then switched on !
If you have not done it already, mark up (tippex or indellible pen) the wires so they have unique identifiers. Then it is possible to say wire 3 is the L-N feed to the living room wire 2 is the switch etc. Otherwise it is very easy to go round in circles repeating the same mistake.

THere are 3 common flavours of 2 way switching, all are described in the reference section - try matching up what you have to any of the diagrams.
You may find you have a borrowed neutral return on the landing light.


PS RE your drawings.
As wired, from left to right, it could be switch L+S/L, incomer L+N, outgoing L+N to another room, L=N outgoing to other room2 and nothing.
But we know that is wrong. Can we confirm which lights elsewhere dont work if the 3 reds are disconnected from each other. One of them will be live in, and others will be lives out to somewhere - but where?
How was the switch wire identified, and is there really a live link between the right most wire aned the switch, or is thre another piece of red+E somewnere. Usually red+E is used for switched lives, or to make up the 3rd core of a 2 way circuit.
could the red tape marked wire be live feed, not 'switch' - how did you identify it?

 

[Advocate]

Woah that's all very confusing.

Re: disconnecting the red wires. Do you want me to disconnect all red wires (there's 4 of them) or leave the "red + earth" connected to the switch wire black? Do you want me to just take them out of the block and then test the lights?

 

[HDRW]

I've drawn a couple of diagrams, hope they help explain things better.

Just a thought - I see the Hall light switch is wired for one-way operation - is it possible that previously there was 2-way switching, with another switch on the Landing, say? If so, and it's been removed, that may go some way to explaining why there are so many wires, and why the strange Live/Earth is there (and may not be needed any more).

Cheers,

Howard

 

[Advocate]

I did try disconnecting the red/earth lead from the switch but when I do that the landing light no longer works.

I've tried just about every combination of red wires I can think of in this damn ceiling rose and nothing gets every light working. The only time the study lights come on is when that red/earth lead is connected in with the switch wire (black) and then they only half (not even half really more like 1/8th) light up, with the hall light also coming on.

I'm beginning to think there may be a short somewhere and that I may have to call a qualified electrician in to fix it all.

Anyone want to employ an A+E nurse for some overtime shifts? :s

 

[mapj1]

Don't mind what order - they are your wires. what I would like is for you to be sure by measurement not just because 'it looks the same' which wires really go where. (red tape is convention, but one not always followed)
If it were me I'd unpick all the 3 reds, and then see which on is actually the only live one. (thats where I'd use the neon, but others will say a proper meter is better, and they are right really, but its not so easy to connect both sides without shorting something out DO BE REALLY CAREFUL - MAINS accross the body can be lethal)

I'd mark that cable as "supply"
Alternatively, if you have an assitant to hold the meter, with all lives broken, note a light that does work (i.e. must be upstream in the daisy chain in the direction of the main breaker. Then turn of the power, and see which wires red to blackresistance changes when you operate that light switch. That is supply. Do not try and measure ohms with the mains power on, it may be the last thing the meter does for you.
Other wires whose red-to black resistance changes with switches operated on lights down stream , are the onward going feed to those lights.

Or without the meter -
Noting which other lights in the building dont work, these must be the loads on th ends of the feeds out. Reconnecting the other wires in turn, L and N to the supply feed wire to see which lights resume normal operation. (turn of the breaker while doing the cnnections please!)

Identify the switch wire with meter on ohms range, as the one whose resitance falls from 'infinite' to 'zero' when the swithc is toggled, or if unlucky, its the one that blows the trip when red and black are connected between L and N of supply (not wise - you can weld up the switch contacts doing this)
Once you have done this, label and repost your drawing if it is not all obvious by then.
All the best.

 

[Advocate]

Unfortunately at the moment I have neither a meter nor a neon screwdriver. I know it's very VERY amateurish to do these kinds of things without either but we're both nurses here so she knows what to do should I be blown across the room (or stuck to the wires, whatever).

Hmmm actually out of the two of us I'm the only one who is advanced life support trained so maybe I should get her to do the wiring

 

[ban-all-sheds]

You need to get a meter.

You need to go back to basics, trace the wires, work out what goes where and what does what, and connect it all up properly with the aid of the wiring diagrams in the For Reference topic.

 

[securespark]

Check your connections!

See the For Reference Sticky at the top of the list.

You need to be able to identify all the conductors: permanent live feed in, out and to the switch, the switched live to the fitting, and neutral and earth conductors.

You need to get a meter.

You need to go back to basics, trace the wires, work out what goes where and what does what, and connect it all up properly with the aid of the wiring diagrams in the For Reference topic.