National Electrical Installation Standards

Standards as High as Your Own

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  • July 1, 1998

    The __ __ __ may waive specific requirements in the Code or permit alternate methods where it is assured that equivalent objectives can be achieved.
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  • July 2, 1998

    Where the Code requires that one equipment shall be 'in sight from' another equipment, the specified equipment is to be visible and not more than __ feet distant from the other.
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  • July 4, 1998

    Where the Code requires that one equipment shall be 'in sight from' another equipment, the specified equipment is to be visible and not more than __ feet distant from the other.
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  • July 5, 1998

    In all cases, the work clearance about electrical equipment shall permit at least a __ degree opening of equipment doors or hinged panels.
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  • July 6, 1998

    Terminals for more than one conductor and terminals used to connect aluminum shall be so __.
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  • July 7, 1998

    Which of the following installations would not be covered by the NEC ? a. ___ optical fiber cable b. ___ underground in mines c. ___ conductors and equipment that connect to the supply of electricity. d. ___ Outside conductors and equipment on the premises.
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  • July 8, 1998

    Which of the following switch types would be most suitable to use for manual operation to provide a means of directly connecting load conductors to a power source, and of disconnecting the transfer switch. a. ___ Bypass isolation switch b. ___ General-use switch c. ___ Isolating switch d. ___ Transfer switch
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  • July 9, 1998

    The copper of copper-clad aluminum conductors must form at least __ % of the cross-sectional area of a solid conductor or each strand of a stranded conductor.
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  • July 10, 1998

    What is the minimum size AWG copper conductor permitted for conductors with a 0 through 2000-V voltage rating.
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  • July 11, 1998

    The allowable ampacities listed in Table 310-16 are based on an ambient temperature which does not exceed __ degrees F.
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  • July 12, 1998

    What is the allowable ampacity of a No. 2 THW copper conductor installed in a raceway which contains two other current-carrying conductors. The ambient temperature is 86 F.
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  • July 13, 1998

    Where lighting outlets are installed in interior stairways of dwelling units, there shall be a wall switch at each floor level to control the lighting outlet where the difference between floor levels is __ steps or more.
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  • July 14, 1998

    In general, ground-fault protection of equipment shall be provided for each feeder disconnect rated __ amperes or more in solidly grounded wye systems with greater than 150 volts to ground, but not exceeding 600 volts phase-to-phase.
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  • July 15, 1998

    In dwelling unit hallways of at least __ ft in length, at least one receptacle outlet shall be provided.
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  • July 16, 1998

    Overhead spans of outdoor open conductors, rated at not over 600-v, shall have a minimum clearance from grade of __ ft when such conductors pass over public streets and roads. a. ___ 10 b. ___ 12 c. ___ 15 d. ___ 18
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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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