Outdoor Lights & Water Feature Setup

[Neadles]

Gents, just want some advice on the domestic side as I'm more an industrial engineer. I have 4 lights and a small water feature going to be remotely switched in my new landscaping project (joys of working shifts time for home improvements instead of tinkering with my track car!). I can get easy access to my CU I just want to know what would be the best option of running a supply:

1. RCD fed side with just an 6A MCB or
2. Non-RCD supplied side with a 6A RCBO to stop nuisance tripping

I do have a spur RCD FU but with out changing the main RCD in the CU I will not have proper discrimination so I'm thinking that RCBO is the way as that's what we tend to do at work with all our annoying lighting circuits outside?

Cheers

 

[telectrix]

RCBO off the non-RCD side of the CU is definitely the way to go. any fault outside will only trip it's own RCBO.

 

[shagbite]

rcbo - a bit dearer but no nuisance tripping.

out of interest, what cable are you using?

 

[dan86]

deffo rcbo

 

[telectrix]

rcbo - a bit dearer but no nuisance tripping.

out of interest, what cable are you using?

round???

 

[Flanders]

I Know an RCBOs safer but could he not use an MCB if its lights and a pump with no sockets or do you need the RCBO for the pump?

 

[telectrix]

anything outside, with the exception of cable on the building fabric. i'd fit RCD protection. OK, it's not sockets, but you have to allow for idiots. if SWA is used, there'll still be connections to flexes.

 

[Neadles]

Thanks for the the quick reply's.

Well I hadn't thought that far yet but there is some existing plastic conduit running from another installation that I was going to utilise, basically it was concreted in with the new drive and garage and takes a welding supply to the garage, I was going to feed some flex I had at work that was in the skip 1.5mm from a contractors lighting job we had done. Am I wrong in thinking then this will be ok with the additional mechanical protection instead of SWA? I am bassically planning on sticking 4 brick lights in a small wall near the garage which will have conduit upto it through the wall to the light fitting in the wall? The water feature has a round cable with a plug on it, designed for purpose obviously, that I will just joint into one of the switch units.

Should it really all be SWA and if so on all the domestic IP6* rated items there all plastic so that would mean joining all the out armours together and back to the supply earth. Am I wrong in thinking if the supply in the house is protected prior to going outside, is the cable ok along as it is sufficiently burier with additional mechanical protection?

Please feel free to correct me I have read the 17th addition and done the course to try and get up to speed, but to honest domestic installations especially outdoors are not my speciality as I don't do it from day to day.

 

[telectrix]

i would feed from CU RCBO in T/E, out the wall into an adaptable IP rated box. from there SWA to wherever you are fitting lights, etc. then fit a IP rated socket for the water feature ( i use remote control ones from byron). the light can be spurred off the socket ( fused down if reqd.) ans also remotely switched.

 

[Neadles]

i would feed from CU RCBO in T/E, out the wall into an adaptable IP rated box. from there SWA to wherever you are fitting lights, etc. then fit a IP rated socket for the water feature ( i use remote control ones from byron). the light can be spurred off the socket ( fused down if reqd.) ans also remotely switched.

Cheers for all that pretty much what I am going to do, all the cable will be in conduit and under 6" of concrete and stone and after all the digging isn't every coming up again!


Just another quick question on outdoors if you don't mind? On requirments of cables, if it is to be buried in concrete does it only have to be 6" deep in a conduit (does it matter if its SWA) and if under soil 450mm in SWA?

 

[telectrix]

under concrete and unlikely to be disturbed, you'll be OK. if you're going to use flex in conduit, then get some hi-tuf.

 

[Neadles]

Cheers for all your reply's, no more for one night I promise!