National Electrical Installation Standards

Standards as High as Your Own

Wednesday, October 24, 2018


If a basic disconnect has cables terminated inside, but is not terminated at the main. Does this device need to be locked out if it is in the "off" position? This is temporary power in a "green" zone, and the client does not want to lock out the disconnect that feeds motors they are wanting to run intermittently. I told them that if a disconnect is terminated, regardless if it is live, must be locked out. It has to be treated as live correct? They are just using the disconnect basically as a switch rather than a means of on/off.

Rob Poston



Hey Rob thanks for your question but it is difficult to understand exactly what you are asking. Guessing maybe you have conductors temporarily installed that are connected to the load side of a disconnecting means but are not terminated at their load end. The NEC does not really address work practices and if the disconnect is turned off and there are no exposed live parts it does not seem to be a violation. If someone were to turn the disconnect on and exposed live parts are present it would violate 110.27. It would make sense to lock the disconnect in the off position to prevent someone from inadvertently turning it on. If this does not address your question please send in additional information.

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.

NECA SAFETY PRODUCTS: NECA publishes valuable electrical safety books and CDs for the industry. Visit to view or purchase NECA safety products.

 CONTACT US: To submit a Code question, subscribe, or unsubscribe from this list, please e-mail: