help requested with wiring twin wall lights

[Lizzylizzy]

There are two outlets on my wall for wall lights. One has two red, one black and two earth wires available. The other outlet has two black, one red and two earth wires available.

There is an on/off switch by the door: one switch turns the ceiling light on/off and the other switch is for the two wall lights.

Can anyone help as regards which combination of wires should be used to connect a light bulb to each of the two wall outlets? I have tried various combinations but cannot get either light to come on.

 

[riveralt]

Your going to need a multi meter to determine which is your switch live?

Do you have one?

 

[Lizzylizzy]

thank you for replying. I don't have a multi meter. Is it essential that I have one or is there a way of working through all possible options to determine the live?

 

[Lizzylizzy]

By way of a postscript: I have just been looking on Amazon and mutli meters are not expensive so if necessary I could purchase one.

 

[riveralt]

If you haven't got one then it will be a long trial and error process.

You will need to first of check at the switch to see if there is a red cable into the Common terminal and a black (hopefully) with a red sleeve in the L1 terminal - this is your switch live.

If this is the case then you will need to trace the black/red sleeve cable from there up to the ceiling rose.

If there isn't a ceiling rose then whatever is behind the ceiling lamp (terminal blocks or junction boxes).

If the switch live is marked (black/red sleeve) at the ceiling rose and the link to the wall lights has been done correctly, then you should see that the switch live is connected to a red cable which runs to your wall lights. This cable becomes your switch live.

At the wall lights the switch live will be one of the two reds. The second red will go to the other wall light.

I'll hold back on part 2 until you have figured out which is your switch live

 

[Lizzylizzy]

thanks again.

unfortunately, I can't easily get behind the switch because it has been fitted into dry boarding and plastered around as well. I do know, though, that the switch was working ok and did turn on wall lights that had been preciously fitted onto the wall - so the link to the wall lights was presumably done correctly.

If one of the two red wires protruding from one of the wall outlets is the live one can I not just try them in turn? I have tried connecting each of the reds in turn to a light fitting (along with the black wire) but this doesn't turn on the light. Does it rely on a correct fitting to the other wall outlet and having them both connected?

As mentioned, I can buy a multi meter but I won't have it until next Thursday so, in the meantime, I'm happy to proceed by trial and error if you have the time and patience to go through the options on the basis of one of the two reds being the live. If this will prove troublesome and if you will still be around next Friday (but it's Christmas Eve) I can wait until then and proceed. Or, if you outline what follows once the live has been identified, I could follow on once I have the multi meter.

regards

 

[riveralt]

I will assume that your new wall lights have L, N and earth connections in some form of terminal block.

If that is the case and given the number of wires you have at each light I feel that you may have to connect both lights up to get them to work.

Normally you would have 2 reds 2 blacks and 2 earths at the wall light connected directly to the ceiling rose. The second wall light would link from the first and would have 1 red 1 black and 1 earth.

We will just have to assume that the reds are live, blacks are neutral and earths are well.....earth

Makes sure the power is off.

At each wall light connect the all the red(s) to the L - black(s) to the N and earths to the earth.
Good luck.

 

[Lizzylizzy]

OK, thanks for that and that's what I will try:

at the first wall outlet, both reds to one terminal and the single black to the other terminal of a regular light-bulb fitting (which has no terminal for earth wires, or metal plate to attach them to, so I'm going to ignore all the earth wires -- can I presume this will not prevent the lights from working if all else is correct?)

at the other wall outlet, both blacks to one terminal and the single red to the other terminal (again ignoring the earth wires).

I'll let you know the result. Thank you again

 

[riveralt]

OK, thanks for that and that's what I will try:

at the first wall outlet, both reds to one terminal and the single black to the other terminal of a regular light-bulb fitting (which has no terminal for earth wires, or metal plate to attach them to, so I'm going to ignore all the earth wires -- can I presume this will not prevent the lights from working if all else is correct?)

at the other wall outlet, both blacks to one terminal and the single red to the other terminal (again ignoring the earth wires).

I'll let you know the result. Thank you again

Stop Don't do that

If the wall lights don't have a terminal block as I described above you cannot do what you are contemplating.

 

[riveralt]

If your wall lights do not have L N E terminal connection then you will have to put one in place first.

I take it your wall lights just have one brown and one blue wire .........

If that is the case then you will have to get a terminal block with 3 terminals for both wall lights.

For each wall light on one side of the terminal block put the reds into the first terminal, the blacks intot the second terminal and the earths into the third.

Then on the other side of the terminal block connect the brown wire to the red wires and the blue wires to the black wires for each wall light.

 

[ban-all-sheds]

I wouldn't advise connecting all the blacks together at a light fitting without a lot more info on what they all are, how the circuit is wired, etc.

With enough terminals in a choc-block you could work it all out by trial and error and not risk any bangs, but using a multimeter to identify at least the switch wire would definitely be best.

Really, if you're going to work on your electrics you should have a multimeter in the same way you have screwdrivers and wirestrippers etc.

Lizzy - avoid the cheap ones from companies like Silverline, Skytronic. Fluke, Amprobe and Draper appear to be the reputable makes on Amazon.

And you don't need to spend money on features like transistor, diode or capacitance testing - a basic model of good make will be a much better purchase than one with bells and whistles

As with any tool, don't go for the cheapest you can find - you should probably be expecting the £20-£30 bracket, although I would say that if I needed to buy one, I'd give serious consideration to the RS own-brand Iso-Tech IDM63N, or despite what I said above, a basic Fluke 10 or 7/300. You are looking at £40-50 there, but they are well made.

Full thread here: http://www.diynot.com/forums/viewtopic.php?t=26282

If you want to invest in something more than just a multimeter, I've always thought this looks ideal for a household starter set - multimeter, voltage indicator (easier & safer for measuring/checking voltage than a multimeter) and dedicated continuity tester, all in a handy case: http://www.amprobe.eu/de_DE/showproduct/115/Junior-Set/

PDF brochure: http://www.amprobe.eu/de_DE/downloadfile/115/beschreibung_1/

All in German, unfortunately, as is the blurb on each product:

Multimeter: http://www.amprobe.eu/de_DE/showproductdata/487/Hexagon_55/

Voltage indicator: http://www.amprobe.eu/de_DE/showproduct/116/2000_α_(alpha)/

Continuity tester: http://www.amprobe.eu/de_DE/showproduct/481/TESTFIX/

but it is sold in the UK - the company is now owned by Fluke, and I guess they haven't got all the websites sorted out yet - contact them (http://www.fluke.co.uk) for info on where to buy.

Right now the English specs are still lurking on the Internet Time Machine from when Beha was an independent company:

http://web.archive.org/web/20060920022629/http://www.beha.com/files_uk/multimeter/93549.pdf

Although the last time I posted this info somebody told me that the site does now have it in English - I've not looked yet....