15. Communication systems When the alarm sensor activates, the panel will “seize” the telephone line and transmit a digital signal to the Central Monitoring Station receiver. The alarm information and required response information is displayed on a computer terminal for operator evaluation and action
16. Central Monitoring Station The receiver sends a handshake tone Panel now sends alarm data After successful reception, a “kiss off” tone is sent Sequence of Events - data transfer takes around 4.5 seconds Panel Dials the receiver