Thought I had best check up on this before I do it ...

I need to connect three low voltage spot lights with three transformers
to the main lighting circuit.

Can I do use a junction box to link the mains feed to each individual
spot? This means that there will be four sets of twin and earch going
into the junction box (I need to extend the T&E to the transformer
position for each fitting).

How should I wire all four T&E's into the junction box? Had a quick
look at one today - the sort where you get four terminals around the
outside and two in the middle. Its going to be a pain to connect all
four into the two terminal blocks in the middle - am I looking at the
wrong type of junction box? Is it acceptable to bridge the terminals to
allow me to connect 2 lives and 2 neutrals at the top of the box and 2
at the bottom bridged together?

Also, how should I terminate the earth from the mains feed. This isnt
needed for the transformers. I presume I should terminate it inside the
junction box on a spare terminal. Is it acceptable to just cut it short
and not use it?

I havent started this work yet before I get told off for not knowing
what I am doing!!

Thanks in advance,

CM.

"Charles Middleton" wrote
| I need to connect three low voltage spot lights with three transformers
| to the main lighting circuit.
| Can I do use a junction box to link the mains feed to each individual
| spot? This means that there will be four sets of twin and earch going
| into the junction box (I need to extend the T&E to the transformer
| position for each fitting).

Yes, but remember that junction boxes are supposed to be accessible. You
might be better going from fitting to fitting to fitting.

| How should I wire all four T&E's into the junction box? Had a quick
| look at one today - the sort where you get four terminals around the
| outside and two in the middle. Its going to be a pain to connect all
| four into the two terminal blocks in the middle - am I looking at the
| wrong type of junction box? Is it acceptable to bridge the terminals to
| allow me to connect 2 lives and 2 neutrals at the top of the box and 2
| at the bottom bridged together?

It would be acceptable, but probably neater to get a bigger (20A or 30A)
3-terminal box. Remember that the outer sheathing must continue to inside
the box ie no coloured insulation visible outside the box.

| Also, how should I terminate the earth from the mains feed. This isnt
| needed for the transformers. I presume I should terminate it inside the
| junction box on a spare terminal. Is it acceptable to just cut it short
| and not use it?

No. You must connect the earths in all the T&Es and run the earths (circuit
protective conductor) right up to the transformers whether or not they are
double-insulated. All mains circuit wiring requires a cpc. There should be a
parking terminal on the transformers for the unused earth. All earths
require green-yellow sleeving.

If the T&E you buy is new colours (brown/blue) and your house is wired in
old colours (red/black) then you also need to buy a little label saying
"this installation uses old and new colour schemes" and stick it on the
consumer unit.

Owain

Charles Middleton wrote:
Thought I had best check up on this before I do it ...

Always a good idea ;-)
I need to connect three low voltage spot lights with three transformers
to the main lighting circuit.

Can I do use a junction box to link the mains feed to each individual
spot? This means that there will be four sets of twin and earch going
into the junction box (I need to extend the T&E to the transformer
position for each fitting).

Yes, a junction box is the obvious and preferred way.

How should I wire all four T&E's into the junction box? Had a quick
look at one today - the sort where you get four terminals around the
outside and two in the middle. Its going to be a pain to connect all
four into the two terminal blocks in the middle - am I looking at the
wrong type of junction box? Is it acceptable to bridge the terminals to
allow me to connect 2 lives and 2 neutrals at the top of the box and 2
at the bottom bridged together?

I wouldn't use a 6-terminal box - too cramped, given you need only 3 or
4 terminals. 3 if there's an existing cable which already carried E, N,
and switched-live, e.g. the cable running to a non-loop-in ceiling rose
you're replacing; 4 if you're using the JB to effectively replace an
existing rose, or existing JB where switch-return wire feeds in.

With 4 cables to join (6 should you be replacing an existing loop-in
rose!), I'd use a larger 30A JB, just to have a little more room to work
in - with just the 4 terminals. One will common up all the Ns, one will
join the switch-return/switched-live to the L of the three transformer
feeds, one will join any perm-Ls you may have (switch feed, loop-in,
loop-out, if that's what your JB is replacing). And the 3rd, or 4th,
will be for your earth conductors.

Also, how should I terminate the earth from the mains feed. This isnt
needed for the transformers. I presume I should terminate it inside the
junction box on a spare terminal. Is it acceptable to just cut it short
and not use it?

NO. All the earth conductors should be properly joined at one of the JB
terminals, should run through to the transformers, and if your
transformers are Double-Insulated/Class-II, *and* the fittings
themselves don't need earthing, you should sleeve the bared earth wire
and secure it to the cable end with a few turns of insulating tape. That
way, should you or a future householder refit with other fittings which
do need an earth, it'll be ready and available, not cut off in its prime.

I havent started this work yet before I get told off for not knowing
what I am doing!!

Thanks in advance,

You're welcome - definitely better to ask ahead of time than the
not-uknown post of 'I took a light fitting down, undid all the wires,
then I joined all the reds together, and all the blacks. Now my fusebox
goes "pop" every time I try to turn the lights on.'!

HTH - Stefek

In article .com,
Charles Middleton wrote:
Also, how should I terminate the earth from the mains feed. This isnt
needed for the transformers. I presume I should terminate it inside the
junction box on a spare terminal. Is it acceptable to just cut it short
and not use it?

Always terminate an earth rather than cut it off. You never know when you
may need it in future.

--
*Friends help you move. Real friends help you move bodies.

Dave Plowman London SW
To e-mail, change noise into sound.