What is the operational load percentage maximum for a fire alarm system battery?

In evaluating the operational load percentage maximum for a fire alarm system battery, it's essential to reference established standards and guidelines that govern fire alarm systems. The correct choice, which indicates a maximum operational load percentage of 250%, aligns with the National Fire Protection Association (NFPA) standards, particularly NFPA 72, which covers the installation, performance, inspection, testing, and maintenance of fire alarm systems.

Operating at 250% of the nominal capacity allows for adequate buffering to accommodate surges in power consumption during alarms, as fire alarm systems often have various components that may draw additional current when activated. This ensures that the system remains functional and reliable, guaranteeing effective performance even under load conditions caused by alarms or system tests.

Primarily, the other options reflect percentages that would not sufficiently support the operational demand of a fire alarm system. For example, a limit set at 150% would not provide enough capacity for peak load events, while 200% and 300% would exceed the recommended operational thresholds, risking battery failure or reduced system reliability. Thus, establishing the correct maximum threshold is critical for the reliability and effectiveness of fire alarm systems in emergency situations.