Splicing together external electrical cable - waterproof connector query

[Rollerball]

I need to splice together some external electrical cable, what type of fully waterproof connector would I need to buy? It will be exposed to all weathers of course.

To explain - I need to replace an external floodlight, but the existing electrical cable is buried in the wall and I'd rather make use of that instead of drilling a new hole and making a mess of routing some new cable.

The existing cable also isn't very long so if I was to remove the fitted cable from the replacement light I wouldn't have much of the old cable to work with, hence the idea to splice the new onto the old.

 

[chivers67]

Depends on the type of cable?

This any use to you > https://www.wiska.co.uk/Products/cat/474/Gel-and-gel-cable-joints/

 

[Rollerball]

Depends on the type of cable?

Good point. The old cable exiting the wall is the stiff grey type with a rectangular profile. However, the fitted cable on the replacement floodlight is a more flexible black cable which is basically round.

This any use to you > https://www.wiska.co.uk/Products/cat/474/Gel-and-gel-cable-joints/

Thanks. So I'd need a connector which would seal fully bearing in mind the above two cable types.

 

[chivers67]

Are you burying it ? Would a Suface mounted Wiska Box on the wall be any good with stuffing glands ?

https://www.wiska.co.uk/en/30/cat/401/junction-boxes/

 

[Rollerball]

Are you burying it ? Would a Suface mounted Wiska Box on the wall be any good with stuffing glands ?

https://www.wiska.co.uk/en/30/cat/401/junction-boxes/

I wasn't planning on burying it. Any junction box would need to be watertight. Plastic too as things tend to corrode fast where I live (there's a fair bit of salt in the air due to me living in a coastal area).

 

[chivers67]

https://www.tlc-direct.co.uk/Products/WK407B.html with the correct type of Stuffing glands M20 one for a flat cable one for a round. Is there an electrical wholesaler near you ?

 

[Rollerball]

https://www.tlc-direct.co.uk/Products/WK407B.html with the correct type of Stuffing glands M20 one for a flat cable one for a round. Is there an electrical wholesaler near you ?

Thanks!

The closest place to me is B&Q ........ but would it be better off ordering online?

 

[chivers67]

I'm not sure if B&Q will have all three items you need. Order it online

 

[opps]

Thanks!

The closest place to me is B&Q ........ but would it be better off ordering online?

B&Q are pants (as are most DIY sheds).

Follow the links provided if you want decent products.

I am not a professional electrician but I too would recommend the Wiska junction boxes. You can buy cheaper ones from the likes of Toolstation but they no where near as good.

 

[Taylortwocities]

Good point. The old cable exiting the wall is the stiff grey type with a rectangular profile.

That sounds like twin and earth cable, which is not suitable for use outdoors.
Maybe better to install a whole new length of outdoor-type cable without having to create a joint.

 

[Rollerball]

That sounds like twin and earth cable, which is not suitable for use outdoors.
Maybe better to install a whole new length of outdoor-type cable without having to create a joint.

That's surprising. It's been there for over twenty years and shows no signs of wear or deterioration.

 

[Taylortwocities]

Maybe it’s lucky enough to be in a sheltered location. Generally, the sheath of T&E PVC-sheathed cable is not UV stabilised. Repeated exposure to sunlight and frosts will break down the outer.
Your cable may, of course,not be T&E. A photo might help.

 

[skenk]

I've yet to see any twin and earth outside that had broken down in the sun to such an extent that the sheath perished

 

[Rollerball]

Maybe it’s lucky enough to be in a sheltered location. Generally, the sheath of T&E PVC-sheathed cable is not UV stabilised. Repeated exposure to sunlight and frosts will break down the outer.
Your cable may, of course,not be T&E. A photo might help.

It's on a south facing wall and gets full sun all day.

I'll try and get a photo some time.

Meanwhile, if I was to use a connector box (as suggested earlier in the thread) would it be a good idea to use silicone sealant just to ensure that the cable entry/exit points are watertight?

 

[flameport]

One of these fixed to the wall so the existing cable enters from the back,
https://www.toolstation.com/moulded-pvc-box-ip65/p91800
cable entry sealed with silicone

and one of these for the flex to the new light.
https://www.toolstation.com/imo-stag-ip68-cable-gland/p83654

wires joined inside the box with suitable connectors.