alarm relay - how to handle alarm?

[hasiosznup]

hi everyone and greetings to all.

I would like to ask if anyone has used the alarm input on the OS6465?
I would like to use this as a door open/close indication.
The alarm is triggered (trap is generated) when voltage is applied to the input - door is open. and ok.
The question is - is it possible to read the moment the door is closed?
I tried to simulate this, but all i catch is the moment the voltage is applied - the loss of voltage (closing the door) does not give any notification. I have tried (after generating the alarm with the door still opened (voltage applied)) clearing alarm state , hoping that the switch will generate the alarm again, because the voltage is still applied (door is open) - but no - clearing the alarm state gives nothing.
Maybe there is another way to record the moment when the door is closed (voltage loss at the alarm input) ?
thanks in advance
best regards
Marcin