Calculation of batteries capacity for a Fire detection and alarm system

Today we post a simplified example for how the capacity of secondary batteries is calculated. For this example, the required duration is 24 hours in quiescent mode and five minutes (0.083 hours) in alarm mode. The calculation will be done for a specific system configuration with a specific quantity of devices and appliances. If the batteries are to be sized for full circuit loading (option 2), the list of initiating devices and notification appliances would be replaced with a listing of the circuits and their full load current capability.