Which statement is true about fire alarm power sources?

Which statement is true about fire alarm power sources?

• A. The system can operate on a single power source.
• B. The secondary power source must be a battery with 12 hours and 2 minutes.
• C. The system requires two sources of power.
• D. The primary source must be solar.

Answer: (C)

Fire alarm systems are built to run on two power sources so they stay active even if one source fails. The normal, building electrical supply powers the system during everyday operation, while a backup energy source—like a battery bank inside the control panel or a separate backup power system—keeps the system running if the main power goes out. The system automatically switches to the backup when the primary source fails, so alarms, notification devices, and monitoring continue without interruption. There isn’t a fixed universal requirement for an exact backup duration like a specific number of hours and minutes; the backup capacity is designed to meet local codes and the system’s design, often aiming to provide enough standby power for a day or more as needed. The idea that only one power source is allowed or that the backup must be a precise 12 hours and 2 minutes is not correct, and while solar can be used as a source in some designs, it isn’t mandated as the primary power.

Fire alarm systems are built to run on two power sources so they stay active even if one source fails. The normal, building electrical supply powers the system during everyday operation, while a backup energy source—like a battery bank inside the control panel or a separate backup power system—keeps the system running if the main power goes out. The system automatically switches to the backup when the primary source fails, so alarms, notification devices, and monitoring continue without interruption. There isn’t a fixed universal requirement for an exact backup duration like a specific number of hours and minutes; the backup capacity is designed to meet local codes and the system’s design, often aiming to provide enough standby power for a day or more as needed. The idea that only one power source is allowed or that the backup must be a precise 12 hours and 2 minutes is not correct, and while solar can be used as a source in some designs, it isn’t mandated as the primary power.