Guys, just bought a brand new house and was trying to fit an outside light. I was surprised to find brown black and grey on the wiring. No matter what combination I use to my fitting (L,N & E), the best I can get is lamp permanently on or nothing. I've initially assumed Brown = Live, Black = Neutral and Grey = Earth, but then remembered that the colour code seems like a 3 ph wiring colour code. Tried all combinations, including leaving one of the wires off and using 2 on the L & N. Still stumped. Any suggestions?
Normally the triple and earth cable is used between two way or intermediate switches and carries only line voltage with no neutral.
To power an outside light often you would need to take supply from a ceiling rose to a switch and then from switch to outside light.
Because there can be a problem with earth neutral faults with outside lights when they fill with water etc. We would normally use a two pole switch rather than single pole used with lights inside the house. This also makes connection easier too saves using a block connector.
Some outside lights are designed to be switched from PIR to non PIR and so one has to read instructions with lamp.
I would always supply as a RCD protected circuit. Water is a problem with outside lights. Also remember Part P and the 150W limit and select items to comply with rules.