2 Way Lighting - via junction box

[oli-c]

I am in the process of installing a new 2-way lighting circuit by taking a spur from the upstairs lighting ring.
However, instead of linking the 2 switches together directly, I would like to use a junction box up in the loft.
Can you tell me whether I have this wiring diagram correct?
Thanks a lot.

 

[Steve]

diagram makes no sense. you have joints in the middle of nowhere, which is fine for circuit schematics but not for "pictoral" diagrams which this appears to be.

The wiring wouldnt work either. Show what is connected where in the JB. a paint drawing is sometimes much better than a fancy drawing.

 

[Spark123]

Lighting isn't normally supplied as a ring, it is normally a radial. What size MCB or fuse do you have?
You haven't shown how you are looking to connect the wires together in the JB?
Have a look here too: //www.diynot.com/wiki/electrics:two-way-lighting

 

[Steve]

This WOULD work. But totally pointless when it could be done without the JB

 

[ColJack]

strange.. the first diagram made perfect sense to me... I must have a more logic oriented mind

yes you can do it like that but as already said you're just making more dificult for the sake of it.. there is no need to use a JB at all..

Proper way...

1 T+E from the old lights to the new one..
1 T+E from the new light to one of the switches
1 3C+E from switch to switch..


Your Way...

1 T+E from the old lights to the JB
1 T+E from the JB ot the new light
1 3C+E from the JB to one switch
1 3C+E from the JB to the other switch..

additional cost also for the JB.. which must remain accessible for testing..

Crafty's drawing is also not the same method as the OP has shown in the first drawing..
the OP is using 3 plate, whereas Crafty is using 2 plate..

 

[plugwash]

additional cost also for the JB.. which must remain accessible for testing..

OTOH only one cable to get down the wall to each switch which may be usefull if you are either trying to re-use existing burried routes or trying to keep your surface routes as disctete as possible.

 

[oli-c]

Thanks for all your replies.

One question...
What do the terms "3-plate" and "2-plate" mean?

 

[ColJack]

3 plate is when the live feed and switch wire both come from one light and go to only 1 switch.. usefull when wiring using T+E cable..

2 plate is when the live goes to one switch, 2 strappers go between switches and the switch wire comes from the other switch.. usefull when wiring long runs with multiple lights in singles..

This page shows various ways of wiring lights..
the first picture is of 2 plate wiring, the second on the same picture shows 3 plate..

the picture at the bottom titled "conduit wiring" is 2 plate..

 

[oli-c]

Thanks for the explanation of 2-plate and 3-plate.

I have re-drawn my original diagram (as some people were confused).

I have done a test with this method, but the Landing Wall Switch only works when the Hall Wall Switch is in the Off position.
Have a I got something slightly wrong?

 

[ColJack]

the wires you have labled as "switch wire grey" are in fact the live feed..

the "live" black cable is the switched live

the brown is the common..

from your diagram it should work.. you must not have the wires exactly as your digram..

 

[jj4091]

your live brown should be connected to the browns going to the common on your switches, but I suspect you have already guessed that.

 

[Lectrician]

your live brown should be connected to the browns going to the common on your switches, but I suspect you have already guessed that.

No it shouldn't.

 

[oli-c]

Nope - none of the above solutions are working. I have checked and double checked all connections - but I am still getting the same result.
The Landing Wall Switch only works when the Hall Wall Switch is in the Off position.
Looks like I'm gonna have to get some in to have a look at it for me.

 

[weepin dog]

how many hall switches do you have.
is the supply you have taken from loft the same as hall (fuse/mcb)

 

[oli-c]

Sorry, not sure what you mean.
There is a switch in hall (quadruple switch for hall, porch, landing and new stair lighting).
There is a switch on the landing (double switch for landing and new stair lighting).

Both the landing and new stair lighting it taken from the same upstairs lighting ring.