Services & DistributionCâu 51 / 110
A feeder supplies a 60,000-VA, 208-V, three-phase load. What is the calculated feeder current?
a.150 A
b.200 A
c.167 A
d.144 A
Giải thích
Three-phase current = 60,000 / (1.732 x 208) = 166.6 A, about 167 A.
Luyện miễn phí toàn bộ 110 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- An emergency system must be capable of supplying power to its loads within what maximum time after normal supply is lost?
- A legally required standby system must supply its loads within what maximum time after loss of normal power?
- Generator output conductors must have an ampacity of at least what percent of the nameplate current?
- A 200-A busbar has a 200-A main breaker at one end. Using the 120% rule, what is the maximum back-fed inverter (PV) overcurrent device at the opposite end?
- A single made electrode (ground rod) must be supplemented unless its resistance to earth does not exceed what value?
- A metal underground water pipe qualifies as a grounding electrode if it is in direct contact with earth for at least how many feet?
Cập nhật gần nhất: · quy trình kiểm tra
Đội Ngũ Biên Tập PrepPass · Đối chiếu với Master Electrician Licensing Exam (NEC-based) · Quy trình kiểm tra