What is the required overcurrent protection for an NPLFA circuit using 16 gauge wire?

What is the required overcurrent protection for an NPLFA circuit using 16 gauge wire?

• A. 7 amps
• B. 20 amps
• C. 15 amps
• D. 10 amps

Answer: (D)

In non-power-limited fire alarm circuits, overcurrent protection is chosen to match the ampacity of the smallest conductor in the circuit. For 16-gauge copper wire, the typical ampacity is 10 amps (with standard insulation and temperature ratings). So the protective device should be 10 amps or smaller, making 10 amps the correct choice. Higher ratings would exceed what the wire can safely carry, and a much smaller rating isn’t the standard sizing for this conductor in this context.

In non-power-limited fire alarm circuits, overcurrent protection is chosen to match the ampacity of the smallest conductor in the circuit. For 16-gauge copper wire, the typical ampacity is 10 amps (with standard insulation and temperature ratings). So the protective device should be 10 amps or smaller, making 10 amps the correct choice. Higher ratings would exceed what the wire can safely carry, and a much smaller rating isn’t the standard sizing for this conductor in this context.