Change light fitting... JB instead of rose?

[unclebob1]

I'm looking to replace my current bathroom light, wires are - 2 pairs for circuit, 1 for switch, and bathroom fan (two wires plus earth).

At present they go into a rose which is in the bathroom side of the ceiling, The new light fitting comes with just a choc block for L N and E, so i need to move/remove the rose into the attic space above.

So I assume best practice is to use a Junction Box in the ceiling and pass down just the switched live, neutral and earth.

Any recommendations for what junction box to put in? Was looking at this:

http://www.screwfix.com/p/crabtree-4-terminal-20a-junction-box/70677

Screw it side ways onto the nearest joist where wire run is practice, and shift insulation away from the wires... anything else i should do as part of the change?
(besides isolation, checking its dead, checking its wired correctly, checking connections are remade correctly, continuity is maintained etc)

 

[wingcoax]

If your wires are long enough just run to terminals in new light fitting,ensuring correct arrangement of cores.

 

[Taylortwocities]

If not enough space in the fitting, then do it in the loft.
Pull the cables through and fit a junction box, in an accessible position, in the loft.

The JB needs to be screwed to a joist and cables properly clipped.

The other place to do this is on the fan isolations switch. You are bound to have one of those?

 

[unclebob1]

If not enough space in the fitting, then do it in the loft.
Pull the cables through and fit a junction box, in an accessible position, in the loft.

The JB needs to be screwed to a joist and cables properly clipped.

The other place to do this is on the fan isolations switch. You are bound to have one of those?

Thanks - cant do it in the isolator switch easily without replacing some of the wires due to length or putting a connector in, so easier to just put the one JB in and assume that its replaced the rose!

 

[unclebob1]

If your wires are long enough just run to terminals in new light fitting,ensuring correct arrangement of cores.

Don't think standard choc block will hold all the wires unless i loop them? 4 wires in neutral, 5 in earth will be a tight squeeze into a standard single choc?

And with that is it OK to have choc blocks individually in the light fitting loose?

So i could have 4 choc blocks loose behind the light fitting where the live, neutral and earth come in, along with the switch connection,

then the return from switch and a link wire from the neutral and earth choc blocks to the light fitting from where the fan isolator is then powered?

 

[ban-all-sheds]

I don't understand why you need to add more than a single-way bit of choc-block in the light, for the loop conductors. And yes it's OK to have it inside the light.

Have you looked to see if you could replace the existing connections with a 4-way strip?

 

[unclebob1]

Only reason is that i think it may be tight to get 4/5 1.5mm cores into the choc block provided... Will give it a go, if it doesn't work or i cant get it properly griped then I'll go with the JB.

 

[ban-all-sheds]

If you are putting more than 3 conductors into any of the terminals in the light you are doing it wrong.

 

[unclebob1]

If you are putting more than 3 conductors into any of the terminals in the light you are doing it wrong.

I've two earths for the circuit, one to the switch box, one to the light fitting and one to the fan... That gives me 5 if all the wires are coming to one place... Should i split these into two choc blocs and bridge the connection?

Likewise for neutral - two coming in, one for light and one for fan gives me 4, again split and bridge?

 

[Taylortwocities]

choc block comes in all sorts of sizes.
Use a bigger one

 

[viewer]

Wago make nice 5 gang connectors.

 

[ban-all-sheds]

I've two earths for the circuit, one to the switch box, one to the light fitting and one to the fan... That gives me 5 if all the wires are coming to one place...

oops - I didn't count the earths... sorry.

Should be max 4 on one side then, as surely the one for the light is on the other side?

Likewise for neutral - two coming in, one for light and one for fan gives me 4, again split and bridge?

Again, 3 in one side, and one in the other, surely?

 

[Taylortwocities]

Or 2 in each side.
Doubling up blocks with a bridge doesnt help as it adds another conductor, and potential point of problems later.