Making underground connections

[jibjob]

Hi Guys,

Been asked to fit approx 8 decking lights into a patio. The lights in question are like this Welcome to Eterna Lighting The connection boxes are suitable for outdoor use but not for burial. Customer wants all cables etc buried. Thought about dispensing with connection boxes and using small adaptable boxes with stuff it glands and filled with blue goo (can't remember what it's called, CEF do it). Maybe, I could even just fill the existing connection boxes with the blue stuff.

Also, what cable would you use to connect boxes together, it needs to be flexible and will be buried in cement. Circuit is suitably protected, 30mA RCD etc. I've used rubberised stuff before but that was loose laid under decking.

Anyone have any thoughts?

Thanks.

 

[swparksey]

I would explain to the client that if he buried the boxes when the light units fail after about 12 months he is going to need a breaker to get them out and have to dig everything up.

Otherwise put some ducting through the concrete or under the slab to make a void for the cables and boxes to live in, just be sure the ducting won't fill with water.

As for cable then this should do the job NYY - Protected Cables

 

[jibjob]

Thanks for reply, wouldn't have thought fittings would fail, they're mains not ELV so no transformers or drivers to worry about, but as with all outdoor stuff you can't really be sure what might happen down the line I guess.

 

[swparksey]

Yep they are all good until they jetwash the patio and water gets into the lamp holder the over time, well you know what happens then.

Hit the thanks button

100mm ducting under the slab then just bury the cables as you suggested