On Monday, 12 December 2016 17:33:06 UTC, Chris Green wrote:
I'm after a doorbell (preferably one which has two or more sounders)
which doesn't use batteries at all. I.e. both the button(s) and the
sounders are mains powered.

You can get mains voltage bells, and mains rated bell push switches, but that means all the wiring has to be mains standard.

A conventional wired bell system with a transformer should run several bells in parallel, or if you use electronic sounders rather more.

If you want a completely power-free system put a magneto generator at the front door and some telephone bells around the place.

Owain