When installing a protective premise fire alarm system, which of the following may comprise the secondary power source?

When installing a protective premise fire alarm system, which of the following may comprise the secondary power source?

• A. A dedicated branch circuit of an automatic starting engine driven generator and storage batteries dedicated to the system with four hours of capacity
• B. A portable battery pack
• C. A solar panel array
• D. Storage batteries dedicated to the system

Answer: (D)

The standby power for a protective premise fire alarm system is supplied by energy stored specifically for the system, so it can operate when the normal power is lost. The best way to meet this requirement is with storage batteries that are dedicated to the fire alarm system itself. These batteries are designed to be charged by the system and to deliver the required duration of operation reliably, independent of other loads. Portable battery packs aren’t fixed or guaranteed to provide the necessary runtime in a building-wide emergency. A solar panel array could supplement power, but it isn’t the standard, reliable standby source by itself due to variability in output and the need for a proven energy reservoir. An engine-driven generator can serve as a standby power source, but it adds complexity (automatic starting, fuel supply, maintenance) and is not the fixed, dedicated energy storage typically specified for primary backup power in many codes. Therefore, battery storage dedicated to the system best satisfies the requirement for a dependable secondary power source.

The standby power for a protective premise fire alarm system is supplied by energy stored specifically for the system, so it can operate when the normal power is lost. The best way to meet this requirement is with storage batteries that are dedicated to the fire alarm system itself. These batteries are designed to be charged by the system and to deliver the required duration of operation reliably, independent of other loads.

Portable battery packs aren’t fixed or guaranteed to provide the necessary runtime in a building-wide emergency. A solar panel array could supplement power, but it isn’t the standard, reliable standby source by itself due to variability in output and the need for a proven energy reservoir. An engine-driven generator can serve as a standby power source, but it adds complexity (automatic starting, fuel supply, maintenance) and is not the fixed, dedicated energy storage typically specified for primary backup power in many codes. Therefore, battery storage dedicated to the system best satisfies the requirement for a dependable secondary power source.