Conventional detectors are simply on/off devices - if there is
no smoke or heat they do nothing. If there is a certain, pre-set
level of smoke or heat, they switch into the 'Alarm' state. Devices
are connected to one circuit, known as a zone, and each circuit is
connected to a control panel. If a conventional detector goes into
alarm, the control panel will be able to identify which zone has
gone into alarm, but will not have the exact location of the
fire or which device went into alarm.
For more information of conventional fire systems, visit the Questions pages.