alarm takes over phone line during arming

[JJsLegacy]

So I am totally new to all of this but I just got my ad2usb attached to my vista20p today and have been testing it out from the remote keypad. Everything seems great but I noticed that when I arm the system it takes over my phone line and kills any call that I may be on. This happens from any keypad so I wonder if it always did this I just never knew since I don't normally arm it while I am home working etc.

So is this a normal behavior? Optional behavior? Why is it doing it?

Thanks!

[kevin]

If that is the only phone line in your home and your alarm is configured to use and dial through it - during events, it will absolutely behave like this.

[JJsLegacy]

Yes thanks - I get it now. I didn't actually realize the monitoring company was alerted during arming vs a fault etc.

I am a total alarm newbie - thanks!