In article ,
fred wrote:
I see, thanks. I'm used to even more basic configurations where opening
the door merely starts a timer and further action is required to disable
the alarm.

The idea is to get it sounding early to discourage entry. There'll be a
shock sensor on the door frame too for an early trip and a v loud
sounder right by the door, again to discourage entry. Arming off the
lock means there's no excuse for (the tenants) not setting the alarm.
It's a 2nd storey flat so the door is the most likely entry point.

I'm not quite clear then how it would be any better than a much more
simple to wire and hide magnetic reed switch in the door?

--
*I got a sweater for Christmas. I really wanted a screamer or a moaner*

Dave Plowman London SW
To e-mail, change noise into sound.