Replacing Outside Lights and Cable-Advice Please

[topgazza]

I did my electrical apprenticeship some years ago and wanted to check on some work for my nephew is the current "method"

Essentially he has some outside lights, three in all, on the back and side of his house. He wants to replace them with new lights and also the cable...which is a bit sad looking. I can do this for him, obviously, and I was going to take a feed out of his current MCB box off one of the existing lighting circuits...no spares I don't think...., which is on the inside of the wall where the first light is so easy peasy....I will then install an RCD (does it need one ?).probably an RCD FCU ..there isn't one at the moment...in the cupboard and take a 0.75 3183 TRS black flex...for outside/general use....through the wall to the first light and extend this cable around the outside for the other 2 lights.

Essentially I am replacing like for like in terms of installation. I know its a simple job but does it look OK?

 

[Adam_151]

A few points to think about:

1) probably technically notfiable to LABC
2) no RCD needed for outside lights
3) 0.75 sounds thin, normally stick to min of 1mm except for pendant drops
4) wheres the functional switch?
5) branching the lighting circuit at MCB is fine as long as circuit can handle the loading
6) Are lights designed to accept a cable run externally?, some are designed to only accomodate one comming through the wall straight into the back

 

[Dartlec]

hi,

The first thing that springs to mind is that you should really have a switch for the lights to isolate them(also helpful to use the override function built into many lights).

I would probably run 1.5 to a switched FCU which could be your isolation, and then run the 0.75 flex from there

Where does the power for this circuit currently run from? If you want to avoid notification for Part P purposes you would essentially have to be replacing a damaged cable, and not altering the protection of the circuit.

I believe I am right in saying that the lights, if they are all on the outside wall of the house, do not HAVE to be RCD protected, as they are not outside the equipotential zone. That does not mean that putting one on is not a good idea though.

....speaks someone who got a tingle off the securing bolts for some outside lights recently because the builders who installed it fitted a badly tightened connection box in the ceiling

if you got a RCD FCU that would cover both I guess.

others may have different views

 

[topgazza]

DOH! Sorry forgot to mention the obvious...There is also an existing light switch in the kitchen, a 2 gang for the outside lights and the kitchen light. Which I will just reuse.

The current feed is from the downstairs lighting MCB...which I guess I will reuse and not fit RCD if LABC notification is required. I think I will "get away" with fitting a switched FCU in the cupboard as isolation and as a "junction box" for the switch wire etc..

I was considering putting in 1.5 black flex cable to give that extra load safety and I feel more comfortable with that anyway...so I will... although the lights will be as follows....60 watt coach lamp by the back door....150w flood above the patio doors at the back..and a 60 watt bulkhead (its out of sight around the side alley so looks don't matter) so no great load.

All on Pirs and all have compression, waterproof glands for the cable entry. I will be wiring them in series of course

Thanks for your replies guys...it clears it up perfectly...I'm obviously rusty on what is currently allowed even after reading the P Part requirements..which I'm happy I fall outside as it is a like for like replacement.

 

[ban-all-sheds]

I will be wiring them in series of course

Then they'll be very dim, if they even light up at all.

Thanks for your replies guys...it clears it up perfectly...I'm obviously rusty on what is currently allowed even after reading the P Part requirements..which I'm happy I fall outside as it is a like for like replacement.

Part P applies to all work on LV and ELV installations in dwellings etc. Not all work is notifiable, but the term "like for like" does not appear anywhere in the legislation, and is not a determining factor.

 

[topgazza]

Surely not B_A S...to both comments

I don't understand why 3 x 240v lights in series..in line I mean.... would run dim ????? Its no different than, say, three downlighters in a room ...or two hallway lights....

Having read the P part requirements it clearly states, intends...paraphrasing...that replacing damaged cable is not notifiable...nor is replacing existing fittings..in this case lights. The only addition would be the FCU...which I'll leave out in that case.

Hence the use of like for like, my words not their....obviously that could apply to a whole rewire....but that would be stretching the point I think...

 

[ban-all-sheds]

I don't understand why 3 x 240v lights in series..in line I mean.... would run dim ????? Its no different than, say, three downlighters in a room ...or two hallway lights....

Having read the P part requirements it clearly states, intends...paraphrasing...that replacing damaged cable is not notifiable...nor is replacing existing fittings..in this case lights. The only addition would be the FCU...which I'll leave out in that case.

Replacing fixed electrical equipment, and a damaged cable for one circuit, is not notifiable.

I did not say it was.

Work which is a controlled service or fitting has to comply with the requirements of the Building Regulations, but those requirements do not necessarily include notification. In other words, just because something isn't notifiable that does not mean that you can ignore all the other requirements.

Hence the use of like for like, my words not their....obviously that could apply to a whole rewire

No it could not - the exemptions from notification listed in Schedule 2B clearly don't include rewires, even if you don't replace the CU.

 

[topgazza]

...yep...I meant parallel..... .....not serial....



I was being Ironic with the whole rewire comment



Advice much appreciated...