External floodlight

[DNO1981]

Hello all

I'm to add an external flood light with pir with a switch indoors to turn on & off I have a RCBO consumer unit
Question is ....
1 - do I come of the lighting circuit into a swith then out to junction box to feed the light
Or
2 - I have a fused spur, shall I come of this into the switch then the outside light

Spur or lighting circuit?
Cheers

 

[pc1966]

I presume this is something like a 50W or so LED floodlamp, and not a old 1kW halogen lamp that would likely trip a lights MCB/RCBO on switch-on?

Then both a 6A RCBO for lights, or a 3A/5A FCU off a RCBO protected circuit, are reasonable options. I personally would prefer coming off the lights supply simply as anyone in the future would expect a light to be powered from the circuit marked "lights".

 

[telectrix]

i'd prefer a D/P FCU so as to be able to isolate it when it fills up with waterand trips your RCBO.

 

[DNO1981]

I presume this is something like a 50W or so LED floodlamp, and not a old 1kW halogen lamp that would likely trip a lights MCB/RCBO on switch-on?

Then both a 6A RCBO for lights, or a 3A/5A FCU off a RCBO protected circuit, are reasonable options. I personally would prefer coming off the lights supply simply as anyone in the future would expect a light to be powered from the circuit marked "lights".

Definitely a LED its 50w ... guess it would make sense of the lighting circuit as there would be a switch in the living room for the outside light..... thanks

 

[pc1966]

Double pole switching is attractive in terms of isolating any faults (including N-E from cable damage, etc), that could also be a simple DP switch off the lights supply.

 

[DNO1981]

i'd prefer a D/P FCU so as to be able to isolate it when it fills up with waterand trips your RCBO.

So come of the FCU rather than the lighting circuit? Then into a switch, I'll be connecting the light so the sensor can be bypassed & turned from inside when we want it on & when off the sensor will be back in operation

 

[SJD]

You can get a double pole switch to put on the lighting circuit!

 

[pc1966]

One example of a DP switch:

https://www.NoLinkingToThis/p/mk-logic-plus-20a-1-gang-dp-control-switch-white/44956

 

[DNO1981]

One example of a DP switch:

https://www.NoLinkingToThis/p/mk-logic-plus-20a-1-gang-dp-control-switch-white/44956

I have brass fittings... Will this be OK

1 Gang 20A Double Pole Switch Georgian Polished Brass Rope Edge

Sparks Electrical Wholesalers sells a wide range of electrical items including 1 Gang 20A Double Pole Switch Georgian Polished Brass Rope Edge Raised Plate.

www.sparksdirect.co.uk

 

[pc1966]

I have brass fittings... Will this be OK

Yes, that looks fine.

Just make sure the light circuit is properly earthed and the CPC (earth wire) is attached to the plate.

 

[DNO1981]

Yes, that looks fine.

Just make sure the light circuit is properly earthed and the CPC (earth wire) is attached to the plate.

Appreciate the advice, I'm going to feed of the lighting point in the living room into this switch, outside into a JB & wire the flood into this ... thats my plan

 

[pc1966]

Appreciate the advice, I'm going to feed of the lighting point in the living room into this switch, outside into a JB & wire the flood into this ... thats my plan

Sounds reasonable.

For cabling outside don't use exposed T&E as it is not UV resistant (often it lasts years if north-facing so not direct sunlight but still bad practice). You can cover it in UV-tolerant plastic conduit as one solution, or use a UV resistant cable such as H07RN-F:

Superlec 3CORE 1.5MM 3183P H07RN-F EPR / PCP FLEXIBLE MAINS CABLE - EN60332-1-2

H07RN-F Cable is a non armoured flexible mains and control cable designed primarily as a trailing cable for use in the supply of energy for portable or mobile equipment.The cable is Ideal for use with transformer pumps, welders grinders, temporary lighting cable and feed cables to heavy mobile...

www.superlecdirect.com

However, H07RN-F is very flexible so needs lots of clips to hold it straight if that matters to you!
NYY-J is another good choice for outdoor fixed wiring use, as it is much stiffer so tend to stay in place, for example:

Superlec 3CORE 1.5MM NYY-J NON ARMOURED MAINS CABLE IEC60502-1

Please note: If you require advice on which cable to use, how and where to install it, it is recommended that you will need to contact the relevant qualified tradesperson for the job as the Superlec Direct Team are not qualified electricians.

www.superlecdirect.com

It is a bit like armoured cable without the steel armour (so not OK for burial according to UK regs) and fine for places you don't expect severe mechanical threats.

 

[pc1966]

Note the minimum bend radius for the likes of NYY-J and similar cables is usually around 12 times the diameter, so around the 12cm mark. That should be born in mind when thinking of taking cable out through a wall and then at 90 deg from there.

In that respect PVC conduit and junctions allow a neater sharper bend for using T&E (bent on flat side) if your route demands it.

Also you can get PVC conduit & accessories in white and black, so if white suites you decor better that might be another consideration.

 

[DNO1981]

Sounds reasonable.

For cabling outside don't use exposed T&E as it is not UV resistant (often it lasts years if north-facing so not direct sunlight but still bad practice). You can cover it in UV-tolerant plastic conduit as one solution, or use a UV resistant cable such as H07RN-F:

Superlec 3CORE 1.5MM 3183P H07RN-F EPR / PCP FLEXIBLE MAINS CABLE - EN60332-1-2

H07RN-F Cable is a non armoured flexible mains and control cable designed primarily as a trailing cable for use in the supply of energy for portable or mobile equipment.The cable is Ideal for use with transformer pumps, welders grinders, temporary lighting cable and feed cables to heavy mobile...

www.superlecdirect.com

However, H07RN-F is very flexible so needs lots of clips to hold it straight if that matters to you!
NYY-J is another good choice for outdoor fixed wiring use, as it is much stiffer so tend to stay in place, for example:

Superlec 3CORE 1.5MM NYY-J NON ARMOURED MAINS CABLE IEC60502-1

Please note: If you require advice on which cable to use, how and where to install it, it is recommended that you will need to contact the relevant qualified tradesperson for the job as the Superlec Direct Team are not qualified electricians.

www.superlecdirect.com

It is a bit like armoured cable without the steel armour (so not OK for burial according to UK regs) and fine for places you don't expect severe mechanical threats.

I was going to use the NYYJ cable 1.5mm & wiska JB & glands make sure it's all IP rated, from the switch T&E out in the JB I'll make sure it's all earthed wouldn't want to risk a shock ....