On 15/05/2016 00:04, Bob Eager wrote:
On Sat, 14 May 2016 22:21:19 +0100, Fredxxx wrote:

This is 24V and need to cable up between closer and switched supply.

I have checked the supply does go off with a fire alarm!

What cable should I use? I'd rather use something other than mains cable
to differentiate between mains and ELV.

I used telephone cable. I ran six pairs from the wiring centre to the
front door, and just used one of those.

The current draw isn't great (on mine, anyway) and the duty cycle is low.

Many thanks for the idea.

Its only a short distance. I would have preferred to have exported an
earth as well, given the cases are metal, and the transformer of unknown
origin.

I was looking for shielded cable or screened twisted pair, then it
dawned on me I can make one conductor earth as well as 0V return!