[align=center]The oddity about using thicker cable and not being very good is also the type of cable.
Flexible alarm cable is stranded wire and is also tinned to prevent Tarnish. Ordinary mains cable is usually plain copper, when this dulls with exposure to water and air, electricity struggles.
It is not widely known, but electricity will only travel along the outside of a conductor not actually through it, on big pylons and underground cables, the 'cable' is often tubular like pipes, so there is more conductive area, so using stranded wire is the best option, plus clean conductors.
The best to use is loudspeaker cable, as long as the conductors are tinned, however alarm cable is ok, but short lengths would be better or double up the cores.
Water can seep into cables with cappillary action and increase resistance, so at the ends keep them in a dry place and seal any terminal boxes with silicon seal.
I would also avoid mixing metal in a joint , some of the connector blocks around have a nice brass connector but have steel screws that rot away and will cuase the connection to fail, better to use crimps, or best and permanant solder.
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