National Electrical Installation Standards

Standards as High as Your Own

?
Wednesday, October 9, 2019

Question:

Re: CQD answer published Thursday, October 3, 2019 - Suspended Ceiling Luminaires

Along with this question. I have a question about the MC cable from troffer fixture to the next fixture. We were asked to mount a support wire for this MC cable independent from the ceiling supports. In the past we used the CADDY clips that were installed on the same wires that also support the ceiling "T" Bars. Our inspector is asking for separate wires to the ceiling for MC cable support. Most of the cables were 10'-12' long. The Suspended ceiling is 9' and the roof trusses are about 18'-20'. We know they are requiring the Earthquake Clips to secure the fixture to the "T"-Bars.

Tom Inman
A

Answer:

Hey Tom thanks for your related question. The inspector is correct. Support wires that are in addition to the ceiling grid support wires (and secured at both ends) can be used as the support for wiring systems as stated in the second sentence of 300.11(B). The independent (additional) support wires must be distinguishable as stated in the last sentence of 300.11(B)(2). The exception to 300.11(B)(2) allows the ceiling support system to be used - only if the ceiling system manufacturer has instructions of how to do that.

ABOUT CQD: The Code Question of the Day (CQD) is NECA and ELECTRICAL CONTRACTOR Magazine’s flagship National Electrical Code (NEC®) public forum for the industry, sponsored by EATON. The daily distribution of Q&A generates a lively dialogue and shares relative Code-based practical responses.

SUBMIT YOUR CODE QUESTION: Click here to submit a question to for inclusion in an upcoming edition of the Code Question of the Day, or email codequestion@necanet.org

CHARLIE TROUT: Charles M. Trout, better known as Charlie, was a nationally recognized NEC® expert and author. He served on several NEC technical committees and is past chairman of CMP-12. In 2006, Charlie was awarded NECA’s prestigious Coggeshall Award for outstanding contributions to the electrical contracting industry, codes and standards development and technical training. NECA continues to provide this public forum in memory and recognition of all his fine contributions that has made the NEC what it is today. 

NECA STANDARDS: NECA publishes the National Electrical Installation Standards™ (NEIS™), a series of ANSI-approved performance and quality standards for electrical construction. NEIS can be purchased in the NECA Store in three formats: a printed or PDF download of a standard or, as an annual subscription service.

NECA SAFETY PRODUCTS & PUBLICATIONS: NECA produces electrical safety publications and products for the industry including jobsite safety guides, handbooks and resource kits. View a full listing of available resources and products »

IMPORTANT NOTICE: Unless the question requests a response based on a specific edition, all answers are based on the latest edition of NFPA 70® National Electrical Code®.

This correspondence is not a formal interpretation of the NEC® and any responses expressed to the questions are opinions and do not necessarily represent the official position of NECA, NFPA, the NEC Correlating Committee any Code-making panel or other electrical technical committee. In addition, this correspondence is neither intended, nor should it be relied upon, to provide professional consultation or services. 

UPDATE YOUR SUBSCRIPTION PREFERENCES: Subscribe or Unsubscribe from this list.