Which table in the NEC provides power limitations for DC power-limited fire alarm circuits?

Which table in the NEC provides power limitations for DC power-limited fire alarm circuits?

• A. Table 12(a)
• B. Table 12(b)
• C. Table 13
• D. Table 14

Answer: (B)

Power-limited circuits are set apart by specific energy limits, so designers know how much current and power a circuit can safely carry. For DC power-limited fire alarm circuits, the NEC specifies those limits in the table dedicated to DC power-limited conditions. That table defines the maximum allowable current and the associated power constraints unique to DC power-limited circuits, keeping the system within safe, fire-alarm appropriate levels. Other tables cover different circuit types (such as AC or non–power-limited cases), so they aren’t used for DC power-limited fire alarm circuits.