National Electrical Installation Standards

Standards as High as Your Own

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Wednesday, August 1, 2018

Question:

In regards to the changes in the NEC 2017 regarding conduits and dissimilar metals. I work in the bakery industry which uses a lot of stainless steel panels and aluminum rigid conduit due to the multiple washdowns that most of the equipment used receives. This is common practice. How is this affected by these codes changes on new installs?

Larry Ledford

A

Answer:

Hey Larry thanks for your question. The change of wording regarding dissimilar metals such as in 344.14 for rigid metal conduit (RMC) has caused concern to some in other industries as well. The wording does not specifically prohibit making connections of aluminum conduit to stainless steel enclosures. There are other rules for corrosion and deterioration protection in 300.6. Nonmetallic fittings can also be used to avoid dissimilar metals from being in contact with each other.

If you have thoughts on what should be required for the 2020 NEC submit your comment by August 30 of this year at:

https://www.nfpa.org/codes-and-standards/all-codes-and-standards/list-of-codes-and-standards/detail?code=70&tab=nextedition

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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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