Cut a very long story short;!. We need to tap of a small amount of power from a county car park lighting system for a CCTV unit. This is fed with a 3 core SWA cable where they have the three conductors arranged as;
Red = Switched Live
Yellow = Earth
Blue = Neutral
They have a box which has a photocell and infra red detector arrangement that switches the live line to power the lights. What we need is a continuously available mains supply at one end of this lot around a 100 metres away.
Question..
Is it OK to change this so that the Yellow now carries the live or swap that for the Red and make the Yellow the switched live and use the Steel wire of the SWA cable as the Earth protective conductor?..
So now this becomes;
Red = Permanent live
Yellow = Switched live
Blue = Neutral
SWA wires = Earth
And of course label it all to denote that one is switched and the other is live etc?..
Cheers..