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.”

  • ?
    Wednesday, July 26, 2017


    Re: CQD answer published Wednesday, July 19, 2017 - Torqueing Terminations

    As published:

    “ It might be good to use those values in the absence of specific manufacturer's instructions but it is specifically required.”

    Or, is this correct?

    “. It might be good to use those values in the absence of specific manufacturer's instructions but it is NOT specifically required.”

    Thanks for a valuable service.

    Cordially, William H. (Bill) Hudson, CBO, MCP

  • ?
    Tuesday, July 25, 2017


    Exemption for Agricultural Bldg. Bldg is to be used for hay storage and maintenance of farm equipment. Can I set a 200a panel with a meter? Wiring to method to be UF

    Joel Hendren



    Hey Joel thanks for your question. Underground feeder and branch circuit cable can be used in agricultural buildings as stated in 547.5(A). It is not allowed to be used as service-entrance cable as stated in 340.12(1) or where subject to physical damage as stated in 340.12(10). The equipment must also be suitable, with no openings, as stated in 547.5(C)(1). Depending on what you mean by "farm equipment maintenance" other requirements could apply such as Article 511.

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.

NECA STANDARDS: NECA publishes the National Electrical Installation Standards™ (NEIS™), a series of ANSI-approved performance and quality standards for electrical construction. Visit for more information. NEISÔ can be purchased in three formats: as paper books, on CD, or as electronic downloads.

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