Smallest external junction box

[stealthwolf]

I need to replace a halogen PIR security floodlight. Currently, the floodlight has 3-core running straight from the light to a fused spur in the loft. Probably a run of 5-6m.

The new LED replacement comes with 1m of 3-core. I need a small junction box. The exterior ones I've seen are 80x80x50mm or similar.

Are there any smaller ones I could use?

 

[jg321]

Opinions on this will vary - but if avoidable I'd rather not have a JB outside, if not only for aesthetic reasons. I've often found with these kind of units, you can replace the flex fairly easily, giving you a longer run into the loft, and then JB in the loft.

Of course, may or may not be an option for your light. I'm no expert though so lets see what others say.

Jon

 

[stealthwolf]

I've often found with these kind of units, you can replace the flex fairly easily

Ordinarily I would do this but supposedly with these ones, the wiring is captive and can't be replaced without breaking open the unit.

https://www.screwfix.com/p/luceco-guardian-slimline-led-pir-floodlight-black-15w/9309k

 

[ban-all-sheds]

I'd rather not have a JB outside, if not only for aesthetic reasons.

Well - that light isn't exactly going to cause Dale Chihuly any sleepless nights...


I would have thought a small JB (a black Wiska would be my choice) would fit on the wall behind the light and not be particularly noticeable. Use decent stuffing glands and have both cables going into the box at the bottom and there shouldn't be any water ingress problems.

 

[Iggifer]

You could back entry into a conduit end box, tiny piece of conduit, then a female conduit adapter, black stuffing gland. Use a gasket between the lid and the box job done. Don't forget to silicone the hole you drill in the back for the cable entry.

 

[ban-all-sheds]

What would the hole in the back be for?

 

[ban-all-sheds]

One of these, fixed to the mounting bracket?

 

[Iggifer]

One of these, fixed to the mounting bracket?

I assumed the cable was coming out of the wall and straight into the old light. I know he said it was a run of 5 or 6m but I, perhaps incorrectly, didn’t think that would be all outside.

If it does, my advice still stands, but with a piece of conduit up to where the cable comes out of the wall from the end box mentioned above, another end box and a hole in that one. T+E clipped down an outside wall looks naff - and is bad practice. Changed some a couple of months ago that had been so sun damaged the sun had destroyed the sheath and the insulation was beginning to break down

 

[ban-all-sheds]

I assumed the cable was coming out of the wall and straight into the old light. I know he said it was a run of 5 or 6m but I, perhaps incorrectly, didn’t think that would be all outside.

I assumed the opposite, on the grounds that unless his walls are 1m thick the short flex wouldn't be a problem.

Making holes in the back of conduit boxes is pretty much inviting water into them.

 

[Iggifer]

I assumed the opposite, on the grounds that unless his walls are 1m thick the short flex wouldn't be a problem.

Making holes in the back of conduit boxes is pretty much inviting water into them.

We shall have to wait and see. The 3C+E could be capped up the wall inside. That would obviously have been the tidier way to do it originally.

And it is, but it's the same as any enclosure, so long as you seal it up well enough - could always entirely fill it with some compound.

 

[jg321]

Well - that light isn't exactly going to cause Dale Chihuly any sleepless nights...

Either I'm too young, too daft, or that was too subtle, but even after looking him up - I don't get it!

 

[ban-all-sheds]

And it is, but it's the same as any enclosure, so long as you seal it up well enough - could always entirely fill it with some compound.

But you can make things easier by only having cable entries at the bottom. Not always possible, I admit.

 

[ban-all-sheds]

Either I'm too young, too daft, or that was too subtle, but even after looking him up - I don't get it!

It was a comment about being concerned about the aesthetics of a junction box given what that light looks like.

 

[stealthwolf]

Thanks all. The wiring will come through an airbrick in the eaves to save having to drill through a wall. There's probably more than a 1 metre drop down to where the light needs to be fitted.

I was looking at some sort of connecting box/junction box that was small enough to hide behind or just above the light so it was relatively concealed.

 

[jg321]

Mostly option 2 from my list then! It’s been a long day!