What type of protection is necessary for all PLFA and NPLFA system circuits?

For PLFA (Public Life Fire Alarm) and NPLFA (Non-Public Life Fire Alarm) system circuits, the requirement for both overcurrent and surge protection is critical due to the nature of their operation and the environments in which they function.

Overcurrent protection is essential because it safeguards circuit conductors and devices from damage caused by excessive current, which can occur due to faults or overloads. Fire alarm systems must remain operational to ensure safety and compliance with fire protection standards, so protecting against overcurrent ensures that these systems can consistently operate without the risk of failure.

Surge protection is equally important because these circuits may be susceptible to voltage spikes from external sources, such as lightning strikes or switching in large electrical systems. These surges can damage the sensitive components in fire alarm systems, leading to malfunctions or unsuitability during emergencies. Implementing surge protection helps prevent such damage, ensuring the reliability and integrity of the fire alarm system.

Thus, the combination of both overcurrent and surge protection provides a comprehensive defense against various electrical hazards that could compromise the operation and safety functions of PLFA and NPLFA systems.