In article ,
"Colin" writes:
lighting circuit at fuse board, not protected by RCD as you want
lights and alarms to work in event of emergency.

Yes... that reminds me. I was wondering the other day why manufacturers
don't combine burglar alarms with smoke alarms. Certainly would cut down on
the wiring(?)

Many burglar alarms support smoke alarms. I've got 3 on mine.

--
Andrew Gabriel