Accessory Voltage?

[Chas823]

At what voltage should I run accessories (points/lights/etc) on my (upcoming) steam and battery powered garden railway? 12v? 24v? I propose to run power in a (buried) conduit along my layout (65m total length), with the mains transformer out of harm's way inside the house, therefore I will need quite a chunky wire size to carry the current without too much voltage drop. Perhaps I need more than 1 circuit? I want to install as much wiring, etc, as I can before I start building the railway itself, then no frustrating demolition 'down the track' (so to speak!)  Can anyone help me with the 'pros and cons' here?
Cheers,
Charles

[MDLR]

For lights in buildings I go for LEDs which I run on 3 volts - I used to put a battery box and switch on each building, but then I didn't leave buildings out....................

Perhaps the aim at the moment might be to run a "ring main" in your chosen voltage(s) with "take off points" where you can connect accessories. As you're talking about powered points, I take it you're going 45mm gauge? Otherwise, use hand-operated points - much less to go wrong!

[Vapouriser]

I remember from when I put the 12 v cabling in my narrowboat - the thicker, higher capacity cable, the less power loss. Cant remember exactly now but I ll try to find it. One thing about 12 v dc you mustnt put a ring main in, at least not out and and backto the battery/ transformer. Cant remember why that either but real electricians told me! I left the 230 stuff to them though. Good luck