How long should it take for a secondary power supply to activate when the primary power drops?

The correct time for a secondary power supply to activate when the primary power drops is 10 seconds. A 10-second activation window allows for a timely response to a power failure, ensuring that the fire alarm system remains operational during an outage. This time frame is critical for maintaining the safety and protection of the premises, as any delay could compromise emergency response capabilities.

In the context of fire alarm systems, immediate power restoration is essential to keep alarm signals functioning and ensure alertness in case of a fire. If the secondary power supply were to activate in longer intervals, such as 30 or 60 seconds, it could weaken the system's reliability and increase risk during emergencies when quick responses are necessary. Hence, the 10-second benchmark is a widely accepted standard in fire alarm regulations and practices, aligning with safety requirements to ensure that alarm systems function without interruption.