Security light wiring

[dantheram]

Firstly hello all,

Secondly i'm not a spark just after some DIY advice so go easy :wink_smile:

I'm trying to wire in an outside light with PIR.

inside the house i have this set-up -

Switched FCU - - - -WALL - - - - PIR light
(3core) (3core)

I would like the SFCU to turn the light on permanently in on position and to PIR activation in the off position. If this is too hard to achieve, or requires another switch adding i will just buy a PIR light with the pulse permanent on function.

P.S. light spur can be isolated by removal of fuse from another FCU further back, feed side.

let know your thoughts, thanks.

Dan

 

[babylonsBurning]

Hi Dan
Is the upstream spur feeding anything else or just the spur for the light?
Im guessing it is, if so then no.
If there is nothing else on the upstream spur stick a 5a fuse in it, then change the downstream spur for a light switch, u will need triple and earth from switch to fitting to achieve what you want.
when u state 3 core do you mean 3 core +earth?

 

[ian.settle1]

Hi Dan
Is the upstream spur feeding anything else or just the spur for the light?
Im guessing it is, if so then no.
If there is nothing else on the upstream spur stick a 5a fuse in it, then change the downstream spur for a light switch, u will need triple and earth from switch to fitting to achieve what you want.
when u state 3 core do you mean 3 core +earth?

As it is a DIYer think it will be 3-Core flex

 

[dantheram]

Hi Dan
Is the upstream spur feeding anything else or just the spur for the light?
Im guessing it is, if so then no.
If there is nothing else on the upstream spur stick a 5a fuse in it, then change the downstream spur for a light switch, u will need triple and earth from switch to fitting to achieve what you want.
when u state 3 core do you mean 3 core +earth?

here is the whole picture -

FCU 13a - - - - 2 gang socket - - - - Proposed light switch - - - - proposed light (pir)

- - - Updated - - -

As it is a DIYer think it will be 3-Core flex

i was told 3 core + earth is needed. so i have potential for switched live.

 

[babylonsBurning]

Unfortunately Dan with this setup it would not be possible/acceptable even with the 3core and earth. If u change the final spur to a light switch the cabling would be protected by the first spur (assuming 13a fuse installed) that would provide (likely) inadequate protection for your lighting cable (might get away with it depending on conductor size, fixing method etc). If you left the final spur in place then the permanent live would not be protected by this spur!

 

[Geordie Spark]

You need to talk to a bloke by the name of Top Cat about this ............... he's something of a legend when it comes to security lights and PIRs.

 

[dantheram]

Unfortunately Dan with this setup it would not be possible/acceptable even with the 3core and earth. If u change the final spur to a light switch the cabling would be protected by the first spur (assuming 13a fuse installed) that would provide (likely) inadequate protection for your lighting cable (might get away with it depending on conductor size, fixing method etc). If you left the final spur in place then the permanent live would not be protected by this spur!

i agree.

so i propose this -

FCU 13a - - - Socket - - - - SWFCU 3a - - - PIR Light (where permanent on is achieved through pulse of FCU switch)

Ok?

 

[babylonsBurning]

Prob the best solution, Only need 2 of the cores + earth, dont cut the other off incase u change the setup in the future!

 

[dantheram]

Prob the best solution, Only need 2 of the cores + earth, dont cut the other off incase u change the setup in the future!

agree,

just needed some better advice than what exists in my mind.

1.5mm rubberised 3 core+e is what i have so all's good.

what is the arragement for a double pole s/fcu, in terms of wiring. i'll have t+e (feed side supp) and the 3 core + e (load side) at the switch site?

sorry for the novice questions

 

[babylonsBurning]

FCU will be marked up, connect as you say, but you only will be using two cores + earth at the switched side, could put spare core in choc block. Should mark up these cores with sleaving with the appropriate colours.

 

[Des 56]

Ditch the fused spur and fit a 2 gang grid assembly in its place

Fuse the light supply down on the one side,then a 2 way switch on the other (1 way = permanent live,other way switched overide

 

[dantheram]

Ditch the fused spur and fit a 2 gang grid assembly in its place

Fuse the light supply down on the one side,then a 2 way switch on the other (1 way = permanent live,other way switched overide

so 1 switch turns the light on perm and off perm (permanent live side) and the other does what?

 

[tommy.dale]

The fuse carriage on one side and a 1g2w switch the other so on one position it is on via pir and you can override when switched

 

[Des 56]

Originally Posted by dantheram
so 1 switch turns the light on perm and off perm (permanent live side) and the other does what?




The fuse will be the overcurrent protection for the circuit,in your case the light

The 2 way switch will have the live from the fuse to the common of the 2 way
The outgoing will have that live at either L1 connection or switched to L2 connection

L1 connection is permanent live to Pir
L2 connection is switched live to lamp holder

 

[dantheram]

Originally Posted by dantheram
so 1 switch turns the light on perm and off perm (permanent live side) and the other does what?




The fuse will be the overcurrent protection for the circuit,in your case the light

The 2 way switch will have the live from the fuse to the common of the 2 way
The outgoing will have that live at either L1 connection or switched to L2 connection

L1 connection is permanent live to Pir
L2 connection is switched live to lamp holder

understand but, at risk of sounding/looking like a spanner, can someone link to the switch in question, please? i can obviously find the 2 way switches but not one with a fuse carriage.

many thanks,

Dan

 

[Des 56]

Grid switch !

There,that should help the quest

2 gang yoke
grid fuse
2 way grid switch
2 gang faceplate

 

[dantheram]

Just had a eureka moment

MK Grid Wiring - Grid Wiring | Screwfix.com

i guess i use the grid fit stuff on that link to build a 3a fuse next to a 2 way switch.

correct??

 

[dantheram]

big thanks to everyone who replied.

off to buy the stuff and i shall report back with the results / disasters

 

[babylonsBurning]

Well done des 56 for the suggestion. Didnt think of this solution. Sorry to mislead you dan!

 

[dantheram]

Quick novice question again.

Live from spur to fuse feed side

live from fuse load side to com on switch

l1 and l2 carrying live and s/live to light

what do i do with the neutrals? connect them together?

Dan