Replacing my external security light

[leeweedon]

Hello,

Just want to fly this up the flag pole and see what mistakes i've may be making in the planing.

I currently have a broken security light (it's weather worn and presumably fkct) It is connected via 3m T+E that goes down and then though the wall in to the house. This joins to a single fused switch. This connects to its only MCB in the CU. There is nothing else on the circuit.


I plan to Remove the old light and replace it with 2x "Pro Twin PIR Spotlight Graphite Sensor Controlled 2 x 42W"

As I prefer having channeling on the side of the house instead of plain cable being 'tak'd' I'll house 2x runs (one to each light) of T&E (1.5m) in some 20mm plastic rigid trunking.

The cable will go in to the house through the same hole where I want to have a dual switch (one for each light) and then on to the CU.

My initial thought are I need a fused switch for this, but would that be over kill?

Any help is greatly appreciated.

Lee

 

[PrenticeBoyofDerry]

What rating is the existing MCB?
Your plan sounds fine, you can use 1.0mm T&E if you wanted to.

 

[leeweedon]

The MCB is 6a

Would a standard switch be fine or do I need DP or fused switches?

Also do I need to notify for this work?

 

[PrenticeBoyofDerry]

The 6A MCB means you do not require to down fuse the circuit via fused connection unit.
I would always advise a double pole switch or double pole isolation for external equipment, you don't need to use double pole, but if your consumer unit is RCD protected you can get power loss to all or a section of circuits from a fault from the outside lights. This fault may not allow you to re-energise the circuit without isolating both line and neutral of the lights, a double pole switch/isolator, will allow you to do this without disconnecting cables.
With regards to notification, you do not need to, if the work is being done in England.

 

[leeweedon]

Excellent, thank you.

Right let's look for a twin double pole switch...

 

[securespark]

If the switches are in a garage, I'd just use a twin accessory box and two 20A DP switches with neons.

If it's inside the house, you could use DP switch modules in a grid.

 

[PrenticeBoyofDerry]

As above your options for double pole isolation on a two gang plate, would be best served by using grid modules. I will source a link for you to browse over.

http://www.tlc-direct.co.uk/Technical/DataSheets/MK/GridPlus.pdf

You can use the components below on single gang back box, but it will need to be at least 25mm deep.
http://www.screwfix.com/p/mk-1-way-20a-dp-grid-switch-white/47279
http://www.screwfix.com/p/mk-2-gang-front-plate-white/84716
http://www.screwfix.com/p/mk-2-gang-grid-frame/81450

 

[leeweedon]

Okay so just looking at the instructions for the light

Manual here : http://www.free-instruction-manuals.com/pdf/p47106231.pdf

This says in needs 3c+e, I have t+e planned. How should I proceed?

 

[PrenticeBoyofDerry]

I think it says 3 core round flex,

It is suggested that 3-core round flexible cable of 1mm² gauge is used.

which will be line, neutral and CPC.

As you say you are routing in containment outside (I would use conduit rather than trunking), you can use twin and earth. But if you wish to use 3 core flex, it makes no difference. If the cable was exposed, rather than contained, I would suggest not using twin and earth but flex suitable for the external environment.

 

[leeweedon]

I've been out and purchased one of the intended security lights.

Looking at the electrics I'm a little confused.

It has a connection for L, E and N, and also L1. The manual also hints on having 3core+earth wire (not individual cores)

How do i wire my T&E to this? Do I just leave out L1 ?

Untitled

• leeweedon
• 14 Nov 2013
• 1

 

[leeweedon]

Ignore that. Sorted it.

 

[leeweedon]

I think it says 3 core round flex,

It is suggested that 3-core round flexible cable of 1mm² gauge is used.

which will be line, neutral and CPC.

As you say you are routing in containment outside (I would use conduit rather than trunking), you can use twin and earth. But if you wish to use 3 core flex, it makes no difference. If the cable was exposed, rather than contained, I would suggest not using twin and earth but flex suitable for the external environment.

I am using T+E inside conduit. PVC rigid stuff... There will however be a small 2" section where the cable will leave the conduit in the the light fixing.... Does this matter? I'm thinking just move the light closer so the cable is covered and use a grommet or seal to cover the gap.

 

[leeweedon]

Thanks for all your help the lights have been installed and work perfectly

Untitled

• leeweedon
• 16 Nov 2013
• 1

 

[objon]

I've been out and purchased one of the intended security lights.

Looking at the electrics I'm a little confused.

It has a connection for L, E and N, and also L1. The manual also hints on having 3core+earth wire (not individual cores)

How do i wire my T&E to this? Do I just leave out L1 ?

Untitled

• leeweedon
• 14 Nov 2013
• 1

@leeweedon. I have the same lights, and don't understand these terminals. How did you solve the problem??

Thanks!

 

[EFLImpudence]

N - neutral
E symbol - (CPC) earth
Arrow pointing to connector with L - Live supply
Arrow pointing away from connector with L1 - Switched live to light.