What is the minimum allowable AWG for a class 3 conductor?

The minimum allowable American Wire Gauge (AWG) for a Class 3 conductor is 18 AWG. This requirement is established to ensure the safe operation of fire alarm systems and to maintain the integrity of the electrical conductors used. Class 3 conductors are utilized for signaling and low-power applications, where a certain gauge is necessary to handle the expected current load without overheating or causing voltage drops that could impair system performance.

Using an 18 AWG conductor provides a sufficient balance between current-carrying capacity and flexibility, making it suitable for the majority of fire alarm systems. This gauge allows for adequate insulation, ensuring that the conductors can be operated safely within their specified voltage and current classifications without risking damage or failure.