Cable and Ducting for Garden Lights

[shbrooks]

Hello all.  I'd like to install a number of lights around the perimeter of my medium sized garden to uplight a few trees and shrubs - probably 4 to 5 lights in total.  Having recently replaced all of our fences, I currently have a trench I can drop a duct into and install the lighting cables at a later date.  I originally thought I could bury a duct and have duct 'T' points which allowed each light to be served by a separate cable.  However, I couldn't find a suitable sized duct with 'T' points, the smallest being 110mm, which I found was too large.

I'm now planning on running a single cable in a duct, which rises above the surface at each lighting point and into a junction box, which then has a tee-off into each light.  The main cable/duct then dips back below the ground until it reaches the next lighting point.  Presuming this is possible and a more suitable, what size cables and ducts would I need?

 

[ProDave]

Steel wire armoured cable, buried direct if you like, at each light point bring it up to a waterproof junction box and loop on to the next one.  you need a big enough junction box to get 3 waterproof glands into the bottom.

[shbrooks]

1 hour ago, ProDave said:

Steel wire armoured cable, buried direct if you like, at each light point bring it up to a waterproof junction box and loop on to the next one.  you need a big enough junction box to get 3 waterproof glands into the bottom.

 

Thank you ProDave.  I'd rather use ducts I think, so I can get the duct in the ground and pull the cable through at a later, and also add/replace any cables if they become problematic in the future.

 

Any ideas what size SWA cable I need?

[ProDave]

It it is just for lighting, 1.5mm SWA is all you need.

[Onoff]

If you can stretch to it then Pratley underground boxes are excellent. 

[Temp]

I would also go with SWA direct in the ground. You can leave a loop where you think you need a light. Then use either a potted junction in the ground or post mounted box.

 

If you use duct I wouldn't use T joints. I'd just bring the ends of the duct up like this..  UUUU  

 

[ash_scotland88]

2 hours ago, ProDave said:

Steel wire armoured cable, buried direct if you like, at each light point bring it up to a waterproof junction box and loop on to the next one.  you need a big enough junction box to get 3 waterproof glands into the bottom.

Is this to "standard?"

Planning on my own garden install and I thought power had to be burried to a depth, gravel, marked etc. Or is that only for running mains to out buildings?

[Temp]

I think the recommended depth is 600mm with 450mm minimum. That's about how deep our swa cables are. Can be shallower if protected. Should be a marker tape above it but don't think ours has. No gravel either.

Edited December 29, 2020 by Temp