Part P non-notifiable is...
- cable enters light from rear, no external connections (new light fitting)
- cable enters however if light fitting pre-existing (cable replacement)
Bollocks really. I prefer to plug lights into a Masterseal socket. A bit ugly I'll grant you, but your mind will soon change when you can prewire a light fitting (and its replacement) sat on the ground then walk up a ladder, fit it to the wall & plug in. A lot better than trying to fiddle with an upside down junction box, whilst balancing on a ladder, which is usually metal, some 20ft up in the air.
No-one is going to plug a hedge trimmer into it and the supply can be (S)FCU protected at 3A as necessary on the inside. You can not however use this with more complicated 4-wire PIR lights. Don't think Masterseal do a "T-earth" pin version.
If it is a PIR, they tend to last longer when sheltered under eaves.
Surprised no-one suggested the obvious cable...
- White 1.0mm NoBurn cable from TLC
- UV ok, outside ok, just adhere to 6x min bend radius
The red is not UV proof and tends to oxidise a bit pink over time.
DP Sw or FCU on the inside? FTE from wherever into it, through rear via 20mm conduit spanning any cavity, into 20mm galvanised BESA box on outside with 6491X earth fed back through conduit to isolator, exit bottom of galvanised BESA box via IP68 gland to drip-loop into light. Most lights are IPx4, or claim to be whilst havin a larf, so do not forget the drip loop into the light fitting.
If you did use FTE with any gland it needs to be a Pratley gland - they are listed on TLCs website.