What is a requirement for the branch circuit supplying fire alarm equipment?

The requirement that the branch circuit supplying fire alarm equipment must use 12 AWG copper or aluminum wire is rooted in ensuring both safety and functionality. This wire size is appropriate for the typical current ratings of fire alarm systems, providing adequate capacity to handle their load without overheating.

Using 12 AWG wire helps maintain the integrity of the system, ensuring it operates reliably under expected current demands, particularly during emergencies when the fire alarm's performance is critical. Additionally, this size strikes a balance between supporting the necessary electrical load while not being excessively large, which could complicate installation and increase costs unnecessarily.

Fire alarm systems are typically designed to operate on specific voltage and current specifications, ensuring they respond promptly to any fire event. Adhering to the proper wire gauge as specified in the applicable codes and standards is therefore essential for both compliance and operational reliability.