Behavior of Disconnecting Keypad From Ademco 128BP Panel?

["Will" <DELETE_westes@xxxxxxxxxxxxxxxxxx>]

What is the expected behavior of any Ademco keypad if you put a relay on one
wire of the connection between the keypad and a 128BP panel and leave the
relay disconnected?   Does the keypad simply go dead, or does it display an
error?   If the relay is connected, how long will it take the keypad to sync
up and be ready for use?   Is there any potential harm to the panel itself
if this relay is in use a few times a day?

The idea we had was to install such a relay to the keypad and use our door
access card system as a way to activate the keypad.   The user comes in and
presents his badge, which connects the relay and activates the keypad for
maybe five minutes.   The user then can use his access code to turn the
alarm system off or on.

The reason we want something like this is that the access codes have a way
of becoming known over time by too wide an audience of people.    Having a
way to secure the keypad with both a physical token, as well as a unique
user code, makes it all the harder for someone to do something trivial like
just steal a code they happen to see someone use on the panel.

--
Will
Internet: westes AT earthbroadcast.com