Security lights - need an isolator?

[sparkybird]

Hi there

Can you clear something up for me?

My college tutor says that I don't need to install an isolator for a motion sensor security light, the supply can just come straight off (eg) the lighting circuit.

However, my boss says that the NIC say that you do using fixed fused spur off a power circuit.

Any thoughts?

SB

 

[Steve]

an isolator is not nessecary. but most people do fit one, be it a lightswitch or a fused spur switch.

 

[securespark]

IMO, it is good practice to wire security lighting off the ring, via a switched fused spur.

Unless the fittings are just pir controlled bulkheads, max 100W, in which case, they could be wired on to the lighting circuit.

 

[diyunotaclue]

also bear in mind if your coming direct off ring without fused spur then
a) you have to isolate mcb which means everything on that circuit goes off when changing lamp
b) ring is likely to be on rcd which could be tripped by water getting into fitting especially if its a cheapy
c) you need to wire it in same size as circuit ie 2.5mm which can be tricky getting into some of the fittins and
d) well..... i dont need a d cos a,b & c were so b****y good !!! good luck