Mạch nhánh & Đi dâyCâu 227 / 521
The NEC informational note recommends that voltage drop on a branch circuit not exceed what percentage of the circuit voltage?
a.5%
b.2%
c.3%
d.10%
Giải thích
The informational note to 210.19(A) recommends a maximum 3% voltage drop on a branch circuit for reasonable efficiency. 5% is the combined feeder-plus-branch recommendation, and 2% or 10% are not the branch-circuit figure.
Trích dẫn luật: 2023 NEC §210.19(A), Informational NoteLuyện miễn phí toàn bộ 521 câu hỏi — không cần đăng ký.
Câu hỏi liên quan cùng chủ đề
- Per 320.40, what must be installed at each termination of Type AC (armored) cable to protect the conductors from the cut edge of the metal armor?
- Per 320.30, Type AC cable must be secured and supported at intervals not exceeding what distance?
- Which cable relies on its metal armor together with an internal aluminum bonding strip to serve as the equipment grounding path?
- For the combined feeder plus branch circuit, the NEC informational note recommends total voltage drop not exceed what percentage?
- A 120 V single-phase circuit uses 12 AWG copper (6,530 cmil) carrying 20 A over a one-way length of 100 ft. Using VD = 2 × K × I × L ÷ cmil with K = 12.9, what is the approximate voltage drop?
- The circuit in the previous scenario has a voltage drop of about 6.6%, well above the recommended 3% for a branch circuit. What is the most appropriate corrective action?
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