What to do with Earth when installing double insulated downlights

I'm not a sparky, so caution...

Light wiring - like those on the sockets - are generally carried out in two ways - a 'ring' (which has the main power cable coming out of the CU, going around all the sockets in that circuit, and then returning to the same connection in the CU), and a radial (which means single cables heading to the lights and daisy-chaining).

Lightings circuits are almost always 'radial', so the supply cable will loop from light to light before ending at the last one on that circuit.

So, if the power cable to that last light ends at that last light, then the earth wire can do so too. Just terminate it as you suggest.

But pros will confirm - I hope...

 

connector block taped up

Or left in sleeving bent over with no copper on show.

See what sparks say

 

A ring final circuit for lighting is a total waste of cable,in fact it's is unusual, haven't seen one in years in domestic wiring.
And I wouldn't not consider using a ring final myself for lighting,when I was at college many years ago,it was not considered good practice in to wire lighting circuits as a ring final, because of problems breaking the ring.

Don't know if the views on lighting circuits being ring final today has changed, some spark on here will comment on that.

Domestic lighting circuits are usually radial, so just terminate the earth in the last fitting.

 

Continue the earth through all the fittings and just 'park' it at the end one.
The earth protects the cable/circuit as well as anything connected to it even if the fittings are double insulated.
It also means the earth is there if the fittings are ever changed in future to ones requiring an earth.
The amount of times I see the earth's just chopped because the person fitting them thinks they're not needed is unbelievable.

 

What do you mean by park it Rulland. I was told to fold over and leave in earth sleeving and out the way

 

I just terminate it, I suppose park it, means the same, in a small terminal block.

Agree Rulland, it's so infuriating seeing earth wire sniped off.

 

That's it mate, or in a choccy block, it's there, but accessible if required in the future.

 

Posted at the same time as Mr Kiab

 

Is this the type of downlights that have that crappy 2 way connector on the top with a flimsly plastic lid.



What you should really do is take a short piece of twin flex from the fitting into a suitable joint box and continue the earths in the JB. Personally if doing it this way a just use a small 20A joint box, others will say that horrific as its got no strain relief on the cables and wont be fastened down, I say as long as the monster that lives under the floor doesn't play with them they will be fine.

 

That is only fit for the bin.

 

Unfortunately there is a fallacy that the live conductors are the most important, ie, without them the light or whatever won't work.
The circuit protective conductor, cpc, is actually the most imperative one to get correct, this is what affords protection during fault conditions etc and could save your life, again, most people do not realise that.

 

I use Wago boxes exclusively these days when there's only a few cables or so involved: Maintenance free, provide strain relief and fit through a downlight hole. No need for a screwdriver at all (better when you're up a ladder).

 

I carry a cpc to every fitting required or not remember the poor gizzer thats going to carry out the next EICR will need it for earth loop.

 

What you should do, is terminate all 3 conductors into chocolate blocks in an enclosure. Then using some 2 core flex wire from the enclosure to the fitting.
Alternatively, you could try to terminate the live conductors in the fitting, and sleeve and terminate the earth conductor into a chocolate block.

 

Many many years ago when I was an apprentice I read something in a book that has stayed with me.It said that when wiring anything you should always make the earth wire the longest so that in the event of a pull on the cable the earth would be the last to go,as you say it's the most important wire,yes without the live or neutral a thing won't work,without a correctly functioning earth there's nothing stopping that piece of kit killing you if it goes wrong.

 

Ban ChocBlocks!

An Ashley/Hager J803/804 is the way to go. A decent enclosure with Wago connectors, feed in (LN&E), feed out to next J803/4 and two feeds through 2 core flex to two fittings

 

nothing wrong with terminal block (choc bloc) when fitted right and checked regularly

 

How many have you come across that are NOT fitted correctly? and how often do you check what is there? And how many poorly made blocks are out there?

For the small extra cost a J803/4 is a lot easier to use. The quality is built in.

 

Correct. Live the shortest so it pulls out first, earth the longest so it maintains protection until last.

Kind regars