Patent ID: 6081197
Filing Date: 2000-06-27
Classification: G08B

Abstract:
A method of monitoring the condition of the battery of a smoke or heat alarm so as to provide a warning of an impending low battery condition, said method comprising:providing a low battery alarm to warn of a low battery condition, the said condition being that of a battery which has depleted to an energy level at and below which it is recommended that the battery be replaced to maintain the full functionality of the alarm device;providing an additional low battery pre-alarm to warn of an impending low battery condition, the said low battery pre-alarm being provided when the smoke or heat alarm battery has depleted to an energy level which is slightly higher than, but close to, the energy level that would generate the low battery alarm, andbypassing or silencing the low battery pre-alarm without disabling the low battery alarm, in the event of an impending low battery condition, should a new battery not be available to immediately replace the depleted smoke or heat alarm battery, with the result that the occupants of the protected premises have several hours or days to procure themselves of a new battery before the battery in use depletes further to reach the energy level at and below which the low battery alarm is generated.