A 480V, 3-phase feeder supplies a commercial building with a total load of 2000kW. What is the minimum overcurrent protection required for this feeder, according to Article 430.53(A)?
- A100A
- B125A
- C150A
- 200A
Exam tip
Always check the specific requirements for overcurrent protection in the applicable code section.
Why D is correct
The minimum overcurrent protection for a feeder is determined by the maximum demand load. For a 480V, 3-phase system, the maximum demand load is 2000kW / 480V = 4166.67A. According to Article 430.53(A), the minimum overcurrent protection should not be less than 125% of the maximum demand load, which is 125% * 4166.67A = 5210.83A. The nearest standard fuse rating is 200A.