security light wiring advice

[chaddy69]

Hi guys newbie here.

Quick question. Want to wire 2 lights out side onto a 2 gang switch.

1 is a standard bulkhead the other is a non pir 500w security light.

want to be able to switch idependantly.

I planned to take the feed from the lighting circuit in the loft.Do i need to run 2 separate feeds from the loft?
Can i run the live neutral and earth to the light fitting and the a separate switch wire to the switch?

Thanks

 

[17thman]

if you can take a permanent live with neutral and earth to the switching position, then you can take a live from com on first switch to com in second switch. Neutral connected together in terminal block, then take the twin and earth cables off to the to light fittings by connecting lives to the L1's respectively and the neutrals connected to the others neutrals in the terminal block. earths to remain connected together to ensure continuity to the fittings.

Is your lighting circuit rcd protected? What is interior cable installation method and route? you should not clip standard twin and earth outside. there are certain regs around being limited to a 150w lamp outside

 

[chaddy69]

That sounds good. thanks.

All rcd protected.

Whats that about 150w limitation?

 

[17thman]

electricians guide to building regs. page 134 10.6.2

 

[17thman]

External lighting fixed to an external surface of the dwelling and supplied from the dwelling must either be

a) automatically controlled to switch off in daylight and switch off when not required and have a maximum lamp capacity of 150W, or

b) energy efficient.

 

[EFLImpudence]

I was just wondering if Part L is like Part P.
I can't find a relevant document.

What I mean is - are these wattage figures actually law or only to be found in 'Approved Document L'?

 

[ban-all-sheds]

They are only in AD L, but as with AD P, it would be an uphill struggle to do something different.

Harder, actually - there are perfectly good alternative standards to BS 7671, but a watt is a watt and a lumen is a lumen the world over, it's not like you could say, "Ah yes, but if I put a German 500W halogen light in it will be just as energy efficient as an English LED".

 

[ASDAPrice]

I was just wondering if Part L is like Part P.
I can't find a relevant document.

What I mean is - are these wattage figures actually law or only to be found in 'Approved Document L'?

When I first read this post, I thought you were comparing Part L to Part P as in the respect of no one seems to even bother abiding by Part P anyhow.

 

[ban-all-sheds]

Well I hope they do - anyone who doesn't should be locked up.

 

[EFLImpudence]

When I first read this post, I thought you were comparing Part L to Part P as in the respect of no one seems to even bother abiding by Part P anyhow.

There is that, of course.

"I have a cfl security light outside but 12 x 50W downlights in the living room."


I was more enquiring if Part L was like Part P.

Part P itself is very straight forward in that it is difficult to argue that electrical work should not be done safely.

Part L is similar in that it states that installations should be energy efficient and use no more power than is reasonable in the circumstances.
This of course is open to interpretation as to what is reasonable in the circumstances.

Then there are the Approved Documents which are not statutory but explain what is involved in complying with the 'parts'.

AD P contradicts Schedule 4 in a few ways so you can choose which better suits your requirements.

As there doesn't seem to be a relevant schedule for Part L I suppose there is only AD L to follow but it may not be correct.

 

[ban-all-sheds]

AD L has guidance on what is considered by the powers that be to be compliant with Part L of the regulations.

And of course, it is only guidance and of course you are perfectly free to use a way to comply which is different to the guidance. You just have to convince TPTB that your way is as good as theirs and you'll be fine.