National Electrical Installation Standards

Standards as High as Your Own

Wednesday, August 1, 2018


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



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.

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