An industrial plant has a feeder circuit that operates at 600V, 3-phase. The maximum load is 1500kW. What is the minimum conductor size required for this feeder, considering a 0.85 service factor?
- A4/0 AWG
- B250kcmil
- 300kcmil
- D350kcmil
Exam tip
Always verify the conductor size based on the actual operating conditions and the code requirements.
Why C is correct
The minimum conductor size is determined by the maximum load and the NEC requirements. For a 600V, 3-phase system, the ampacity is 1500kW / 600V = 2500A. With a service factor of 0.85, the required ampacity is 2500A / 0.85 = 2941.18A. The minimum conductor size for 2941.18A is 300kcmil according to Table 310.16(B)(16).