IP65 Junction boxes

[DARTHVADER]

Hi.

I'm installing two 150 watt external lights fed via ring main/rcd outlet to 1.5 hi tuff cable.


I intend to site two IP65 junction boxes next to each light fitting, feeding the hi tuff to each box and then feed the lights from the junction boxes with some arctic flex.

The IP65 have flexible membranes at the holes around the box and also in the back of the box.

My question is do the membranes have to be cut and then fitted with a compression cable gland/lock nut, or will the cable just push through the membrane, which appears will fit snugly around the cable. I cant see any way of ensuring the cable gland will remain central to the membrane, which appears to large for the gland.

Perhaps junction boxes with 20mm solid knock outs would be better for cable glands? if there is such a thing?

Hope this makes sense!

Thanks,
DV

 

[Spark123]

With the one's I'm thinking of which have a push on lid you just pop the cone grommet out and fit a compression gland, think these are the same:
http://www.tlc-direct.co.uk/Products/GWBX3315.html
I also like to use a bit of silicone sealant to guarentee any top blind grommets are nicely sealed.

 

[Monkeh]

If the boxes you have are like these all you do is poke a small hole in the membrane and push the cable through.

 

[DARTHVADER]

Thanks chaps,

Its these junction boxes I have...

http://www.tlc-direct.co.uk/Products/LB9025.html

They definitely have flex mebranes marked M2O. The glands just dont seem like they will fit?

 

[Monkeh]

You need to remove the grommets and fit the glands properly. The holes on those boxes should be 20mm.

 

[DARTHVADER]

Hi Monkeh,

That's easier said than done. I have tried that on one and the whole gland is now out leaving a 23mm hole (id) with a series of openings around the outside of the hole, i.e. some one open, then one closed, one open etc etc all around.

 

[Monkeh]

You need to score them out with a sharp knife or use a holesaw, then.

 

[DARTHVADER]

Cheers just tried that with a stanley type knife, and the flex membrane on the jb is meeting up tightly & snugly with the back of the cable gland.

Thanks for replies and help, sorted !

 

[DARTHVADER]

Hello,

Thanks again for your help on this, I have one more question.

Where the cable enters the adaptable j.b. via the gland, is it a must that the cable should be looped underneath for rainwater run, or will gland seal sufficiently if its ran straight into the top of the box?

Thanks in advance.

 

[Chri5]

Hello,

Thanks again for your help on this, I have one more question.

Where the cable enters the adaptable j.b. via the gland, is it a must that the cable should be looped underneath for rainwater run, or will gland seal sufficiently if its ran straight into the top of the box?

Thanks in advance.

Gravity !!!!!

Under, never over.

 

[DARTHVADER]

Guess that must mean a loop then Chri5 ? !

B***** I've installed it now!!

 

[ban-all-sheds]

So you asked the question at 15:03, then ran out and installed it without waiting for an answer?

That wasn't very smart.

A gland at the top will leak anyway.

 

[flameport]

On their own, the membranes fitted to those boxes are useless, since even if they seal properly around the cable (unlikely) there is nothing to stop the cable being pulled out of the box.

 

[DARTHVADER]

perhaps it was a rhetorical question.

No, in seriousness it was already installed, and I hoped the answer may have been that the gland would seal it.

I'm now faced with adding a longer cable to feed underneath , hey ho! lesson learned.

 

[ban-all-sheds]

And a new box if you've poked a hole in the top.