There's no such thing as an attack alarm, and no evidence has been posted of a panic alarm or its activation. If there was any type of alarm installed, surely JB would have known about it and mentioned it years ago.
There was a panic alarm installed, without being too specific about the location of the button (in case it is still active), it is downstairs within five or six metres of the location where Ralphs body was discovered.
Other details about the alarm, such as it being a shared or second line, or whether it was a silent alarm or not, I do not know. I've also seen nothing which indicates that the alarm was activated on the night of the murders, I've been told that it was not.
I'm also led to believe that there was a burglar alarm fitted although I have no details about it. Could a panic alarm and a burglar alarm be connected in any way, or would they be stand alone systems?
There are just a few vague references, such as:

I've seen a reference in Ann's notes or statements, plus a reference to an alarm in a typed list of some sort, I'll dig them out if I can find them.