In a circuit feeding thirteen lighting fixtures rated at 1.25 A each (LEDs drawing 90W per fixture), the minimum conductor size is

In a circuit feeding thirteen lighting fixtures rated at 1.25 A each (LEDs drawing 90W per fixture), the minimum conductor size is

• A. 14 AWG
• B. 10 AWG
• C. 12 AWG
• D. 16 AWG

Answer: (C)

The main idea is sizing the conductor to carry the total load on the circuit. Add up the current for all fixtures: 13 × 1.25 A = 16.25 A. The conductor must have an ampacity at least equal to that load. In typical copper conductors, 14 AWG is rated around 15 A, which is not enough for 16.25 A. 16 AWG is even lower, so it also won’t work. The next size up, 12 AWG, has an ampacity around 25 A, which comfortably covers 16.25 A. Therefore, the minimum conductor size is 12 AWG. In practice, this would usually be paired with a 20 A breaker.

The main idea is sizing the conductor to carry the total load on the circuit. Add up the current for all fixtures: 13 × 1.25 A = 16.25 A. The conductor must have an ampacity at least equal to that load. In typical copper conductors, 14 AWG is rated around 15 A, which is not enough for 16.25 A. 16 AWG is even lower, so it also won’t work. The next size up, 12 AWG, has an ampacity around 25 A, which comfortably covers 16.25 A. Therefore, the minimum conductor size is 12 AWG. In practice, this would usually be paired with a 20 A breaker.