Security Lights

[electrics_new]

Hi

I am a newly qualified and would appreciate some advice.  I am about to install a Security Flood light (with PIR Sensor) at a customers property.  For this I will be using a spare MCB on the consumer unit. I want to install an on off switch for maintenance and was wondering do I need to use a junction box to run a separate live feed and switched live or can I just do the following:

from the MCB in the CU terminate the 1.5 twin and earth into a standard one gang one way light switch (connect lives together) and put two ends of the live into the switch > run the other end of the cable into the security light ???  

The MCB in the CU is on an RCD.

Please advice.......... 

Thanks in advance.

apologies in the above I was suppose to say:

from the MCB in the CU terminate the 1.5 twin and earth into a standard one gang one way light switch (connect neutrals together) and put two ends of the live into the switch > run the other end of the cable into the security light ???  

from the MCB in the CU terminate the 1.5 twin and earth into a standard one gang one way light switch (connect lives together) and put two ends of the live into the switch > run the other end of the cable into the security light ???  

 

[ProDave]

It sounds like you are trying to describe "loop at the switch" wiring which is perfectly normal.

But surely it's the two neutrals you join together (in a terminal block) then L in from the CU into the switch, and switched live out from the switch to the light.

Or are you trying to wire the switch as an override switch? in which case you will need 3 core & earth from the switch to the light.

 

[Doc Hudson]

Welcome to the forum, If I am understanding you correctly, you are just asking if it is acceptable loop your cable connections at the switch rather than having a separate junction box? In which case the answer is yes. Providing the enclosure is big enough to contain all of you cable terminations, with no exposed unsheathed conductors then carry on as you suggested. If the switch is to be a surface pattress box, then it is may be best to go use the deeper box as used on a socket rather than a shallow light switch pattress, it will give you more room for your terminations.

Doc H..

 

[electrics_new]

thank you Doc Hudson.

 

[NozSpark]

The only thing that I would add to the above is that you are installing a new circuit that could possibly require Part P notification (maybe?) and it will also require an EIC.

To keep the job simpler add it to a lighting MCB and then its only an alteration to an existing circuit and therefore only a MWC required,,,, again Part P (possibly maybe?) but dont know now days :C

 

[electrics_new]

Doc Hudson.

What I want to achieve is use to use the switch for (isolation purpose) also so that the switch can be double flashed (turned on an off in quick succession) so that the flood light will stay on permanent.

Am I doing the right thing here ?

Thanks

 

[alpha spark]

Twin from cu to switch and twin from switch to light join neutrals in a connector.

However I wouldn't use twin outside so I'd put it some PVC tube

As others said double up with existing cct so to avoid notifying via part p

 

[pewter]

new part-p document

section 2.2  (i) part-p applies to   outside the dwelling for example fixed lighting

 

[col]

I'd consider using a DP switched fcu, easy to isolate for service or if there's a fault and can use the switch to control the light at the same time