| 摘要 |
<p>A controlling interface unit (3) is linked to a plurality of event sensors (1) associated with a premises. There is at least one means of establishing communication, using wired communication lines (4, 7; 6, 10) or radio transmissions (5, 8; 9, 13) between this interface unit (3) and, on the one hand, a remote alarm receiving centre (11) for monitoring the sensors (1) at the premises, and, on the other hand, a remote auxiliary facility (14) for filtering out potential false alarms from those premises. The interface unit (3) is capable of routing signals originating from a selected type of sensor (1) to the auxiliary filtering facility (14) instead of or in addition to transmitting the same signals to the alarm receiving centre (11). Depending on the circumstances feedback signals may then be transmitted from the auxiliary filtering facility (14) to the controlling interface unit (3) to negate an alarm condition. Optionally, a memory unit (15) may be linked to the controlling interface unit (3) to store data from the event sensors (1) for a limited time period. This data is then transmitted to the auxiliary filtering facility (14) along with any signal from the selected type of sensor to assist in determination of whether the alarm is valid.</p> |
