"Owain" wrote in message
xena wrote:
4) Do I need 12v wire or will 230v cabling do?

2.5mm is good (using conventional ratings for mains installation use) at
up to about 20A, but that's only 240 W at 12V. Voltage drop will also be
high (you'll lose quite a lot of your energy in resistance in the wires)

And if you're using 5A switches you'll only get about 1 bulb per switch.
(I'm assuming ~55W bulbs)

Ok, I remember the calculations now P=V*I so I'll make sure I bear the
current in mind when I choose the bits.

Cheers.