National Electrical Installation Standards

Standards as High as Your Own

Tuesday, September 11, 2018


Love the service you provide.

While it’s clear in 250.64 that a grounding electrode conductor metal conduit requires bonding at both ends, does this rule apply to IT equipment bonding with a bonding conductor sleeved in a metal conduit?

Ed Sim



Hey Ed thanks for your question and the compliment. You are correct grounding electrode conductors installed in ferrous metal raceways and enclosures must be bonded at each end as stated in 250.64(E). This is to minimize the choke effect of ferrous enclosures. Communication systems have specific rules in 770.100(A)(6), 800. 100(A)(6), 810.21(D), 820. 100(A)(6), and 830. 100(A)(6), that also require bonding conductors and grounding electrode conductors in metal raceways to be bonded at both ends. You don't mention what the Information Technology Equipment is for but Article 645 does not have the same requirement. Possibly it should, if it performing the same function, and you can submit a Public Input to add that rule for the 2023 NEC.

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