Rubber grommets vs comp glands

[IfInDoubtDIY]

I’m sourcing a junction box for an outdoor project - replacing a pair of non-working floodlights. It’s not possible to push cable for the replacement light through the wall so I need an outdoor junction box.

I found one like this: https://www.screwfix.com/p/ced-ip65-24a-5-terminal-weatherproof-outdoor-adaptable-box-80mm-x-52mm-x-80mm/14556

Apparently the knockouts are rubber so you just make a hole smaller than the cable and push it through. However I am considering using M20 glands instead- would this be overkill?

 

[JohnW2]

Apparently the knockouts are rubber so you just make a hole smaller than the cable and push it through. However I am considering using M20 glands instead- would this be overkill?

Not really 'overkill' - the glands would probably provide a closer-to-certain water seal, since with the rubber thingies, it all depends to some extent upon how 'correct' are the size and shape of the hole you make in it.

 

[IfInDoubtDIY]

Not really 'overkill' - the glands would probably provide a closer-to-certain water seal, since with the rubber thingies, it all depends to some extent upon how 'correct' are the size and shape of the hole you make in it.

Thanks John.

 

[Murdochcat]

Wisla 308 is the best option

 

[IfInDoubtDIY]

(Done in a Sir David Attenborough voice)

Here we see that rare yet not uncommon creature. The forum user who comments on a post without actually answering the question that was asked.

 

[evdamadiynot]

(Done in a Sir David Attenborough voice)

Here we see that rare yet not uncommon creature. The forum user who comments on a post without actually answering the question that was asked.

Yet another creature, often found under bridges predating goats,and yet displaying the same trait.

 

[sparkwright]

I’m sourcing a junction box for an outdoor project - replacing a pair of non-working floodlights. It’s not possible to push cable for the replacement light through the wall so I need an outdoor junction box.

I found one like this: https://www.screwfix.com/p/ced-ip65-24a-5-terminal-weatherproof-outdoor-adaptable-box-80mm-x-52mm-x-80mm/14556

Apparently the knockouts are rubber so you just make a hole smaller than the cable and push it through. However I am considering using M20 glands instead- would this be overkill?

Be careful - because some of these 'holes' in outdoor junction boxes aren't actually 20 or 25 mm.
Murdoch is right, a Wiska may be better.

 

[IfInDoubtDIY]

.

 

[sparkwright]

Everyone keeps telling me I absolutely NEED a Wiska! Well that’s all very well but we don’t have any electrical wholesale places near us that sell Wiska boxes, and I’m not paying £15.99 for delivery. Screwfix don’t do Wiska boxes!

If you can't fit a 20mm gland to the box you want to use, then simply poke the cable through the grommet-type material - preferably at the BOTTOM of the box to allow moisture to escape.
Secure the cable to the wall with cable clips to prevent the cable from being yanked out of the box.

 

[sparkwright]

Looking at the specification of the box you would like to use, the knockouts are 20mm, so 20mm glands should fit.
But again, try to use the bottom entries, failing that, the side entries.

 

[blup]

(Done in a Sir David Attenborough voice)

Here we see that rare yet not uncommon creature. The forum user who comments on a post without actually answering the question that was asked.

It’s a forum not an interrogation, people comment on other responses or just make a point. Some of the longest threads shed the OP’s point within a few posts