National Electrical Installation Standards

Standards as High as Your Own

The National Electrical Code is the bedrock of the electrical construction business.

Do you know all the ins and outs of the Code? NECA and Electrical Contractor magazine are pleased to present their daily online feature, “Code Question of the Day,” Sponsored by Eaton.


  • ?
    Monday, November 18, 2019

    Question:

    The answer to last Monday's question did not get published on Tuesday November 12 so we are republishing it.

    I have a stepdown transformer 480V-120V. Usually for single phase, 120 Volts is line to neutral, is there any code violation per NEC 250.26 if the connection is 120 Volts line to line, both conductors are ungrounded? 

    Jesus Santos
  • ?
    Friday, November 15, 2019

    Question:

    Charlie,

    Our apprenticeship class is discussing the following: 358.26 (EMT) states “there shall not be more than the equivalent of four quarter bends (360 degrees total) between pull points (this is also stated in other articles)…..My question is whether a 180 degree bend would be acceptable as part of the total 360 degrees.

    Some in the class say the code is not prohibiting the 180 degree bend, others feel that 90 degrees would be the implied maximum for any bend.

    We would appreciate your input.

    Sal Genovesi
    A

    Answer:

    Hey Sal thanks for your question, it is good to see that you are having NEC discussions. You are correct the maximum 360 degrees of bends between pull points is typical in many raceway articles in the XXX.26 section. Those sections do not limit each bend to 90 degrees so a 180 degree or even a 360 degree bend would not be a violation but they also don't make a lot of sense in an actual installation. Keep having those discussions.

ABOUT CQD: NECA’s Code Question of the Day (CQD) is a leading National Electrical Code® forum for NECA and the industry. The CQD generates a lively dialogue and relative practical and Code-based responses to an ever-increasing and interactive audience.

IMPORTANT NOTICE: All answers are based on the latest edition of the National Electrical Code®, unless the question requests a response based on a specific edition. This correspondence is not a formal interpretation of the NEC®. Any responses expressed to the questions are opinions and do not necessarily represent the official position of NECA, NFPA, or any technical committee. In addition, this correspondence is neither intended, nor should it be relied upon, to provide professional consultation or services.

ABOUT CHARLIE: Charles M. Trout, better known as Charlie, was a nationally known NEC® expert and author. He served on several NEC® technical committees and is past chairman of CMP-12. In 2006 Charlie was awarded the prestigious Coggeshall Award for outstanding contributions to the electrical contracting industry, codes and standards development, and technical training. Charlie was also a member of NECA’s Academy of Electrical Contracting. Charlie’s experienced team of industry experts keep the CQD dialogue and discussions active and informative in the spirit of the man himself, as he wanted.

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