Outside lights

[sbx]

I want to replace an old halogen security light with a more pleasant rope light on our patio. The security light has its own switch inside, and is on the RCD protected downstairs lighting circuit. There is an earth on the cable.

I've not bought the rope light yet, but most of these are 12v with an adaptor to plug into a 3 pin socket. Can I simply replace the security light with an outside socket to plug in the adapter? My worry is that someone may one day see a 3 pin outside socket and plug in something inappropriate (though it is 2 metres above ground level).

 

[Taylortwocities]

There are many aspects to this. First of all, it is permissible to put a 13A socket on a lighting circuit (there is ONE person around here that disagrees with the REGULATION. Best to ignore his personal opinion.)
The downside is that, yes, it is possible that someone might climb up a ladder and plug in a MIG welder, or a lathe. The worst that will happen is that the 6amp MCB on the lighting circuit will trip. So no life-threatening incident there!
Mark the socket as
“6amp. Lights only”

If your rope light is powered through a plug in supply (wall wart) then you won’t be able to get that in an outside socket, as you won’t be able to close the lid. Best to get a large weatherproof box and put your socket and power supply in there. Or have the socket indoors.

 

[ericmark]

The regulations say "Every installation shall be divided into circuits, as necessary, to:
(iii) take account of danger that may arise from the failure of a single circuit such as a lighting circuit
(iv) reduce the possibility of unwanted tripping of RCDs due to excessive protective conductor currents produced
by equipment in normal operation"
It does not say much else as to loads on the lighting circuit. Be it a socket in the loft for a TV booster, or an outside socket for a access lamp, it does not stop you using a 13 amp socket.

In fact it is common to find the whole of house split into two circuits, although a RCD does not monitor current used, it does work on current, so "Circuit. An assembly of electrical equipment supplied from the same origin and protected against overcurrent by the same protective device(s)." applies.

Although many it seems do not think so.

However an outside lamp tripping the supply due to earth fault must be more common than due to over load.

So in real terms down to a risk assessment, what do you think the risk is if some one plugs in the lawn mover and trips your lights, how likely is that going to happen at night when lights are required?

 

[JohnW2]

The regulations say "Every installation shall be divided into circuits, as necessary, to:
(iii) take account of danger that may arise from the failure of a single circuit such as a lighting circuit...

The regs do say that, but I really don't think that many people would believe that to be a reason for not supplying an outside light from a lighting circuit.

As always, some common sense always helps!

Kind Regards, John

 

[winston1]

As always, some common sense always helps!

And common sense says you don’t put a 13 amp socket on the lighting circuit. You can get 12v adapters with wire ends rather than wall worts. Get one of those.

 

[sparkwright]

They do make an outside socket with a cover big enough to accommodate a 'wall wart' adapter.

 

[plugwash]

I want to replace an old halogen security light with a more pleasant rope light on our patio. The security light has its own switch inside

If it's reasonably easy to do so (i.e. if the neutral runs via the switch location) i'd be tempted to make the switch a double pole one.

My worry is that someone may one day see a 3 pin outside socket and plug in something inappropriate (though it is 2 metres above ground level).

An outdoor socket only works if the power brick has a regular plug and cord rather than being supplied in wall-wart form *and* the power brick is waterproof. There is also the worry of misuse as you suggest.

Fitting a socket inside a regular weatherproof enclosure solves the space issue and if the enclosure requires a tool to open mitigates the misuse issue but creates another problem, how to get the cable from the light (which will likely already be terminated at both ends so can't be passed through a normal gland into the enclosure.

Timeguard make a couple of wall mount enclosures with a socket strip inside and with cable entries designed to accomodate cables that have stuff on the end. It comes in two versions, a smaller one with a 2 gang socket strip and a larger one with a 4 gang socket strip. The instructions don't say how the lid is fixed down but from the pictures it appears to be screwed down which reduces the probability of misuse.

https://www.tlc-direct.co.uk/Products/SMWP401.html

https://www.tlc-direct.co.uk/Products/SMWPM02.html

 

[JohnW2]

An outdoor socket only works if the power brick has a regular plug and cord rather than being supplied in wall-wart form ...

As sparkwright has said, one actually can get outdoor sockets designed to accommodate wall-warts etc. - such as ....

Kind Regards, John

 

[JohnW2]

And common sense says you don’t put a 13 amp socket on the lighting circuit.

Do you believe that it is always acceptable to over-ride an explicit regulation (and advise others accordingly) when your personal opinion is that the regulation does not correspond with common sense?

 

[winston1]

Do you believe that it is always acceptable to over-ride an explicit regulation (and advise others accordingly) when your personal opinion is that the regulation does not correspond with common sense?

Yes, when that reg is not statuary and clearly wrong and dangerous.

 

[Taylortwocities]

Yes, when that reg is not statuary and clearly wrong and dangerous.

When it is you that is clearly wrong.

It would seem that you feel free to advise others that any particular regulation is wrong merely because you disagree with it.

In your words, in my opinion, it is you, that is

clearly wrong and dangerous.

 

[bernardgreen]

And common sense says you don’t put a 13 amp socket on the lighting circuit

There is common sense and then there is Winston1's opinion.

 

[JohnW2]

Yes, when that reg is not statuary and clearly wrong and dangerous.

"Not statutory" is irrelevant. People come here for advice as to whether something does, or does not, comply with 'the regs' (BS7671) - commonly to determine whether it would be acceptable to, say, an LABC or EICR inspector. No BCO or EICR inspector could 'fail' something which is fully compliant with BS7671 "because winston's opinion is that it is 'wrong and dangerous' ".

... which is, of course, the root of the problem. As so many others have reminded you, in these situations the "wrong and dangerous" is simply your opinion, often/usually not shared by others, and nothing more than tht.