National Electrical Installation Standards

Standards as High as Your Own

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Thursday, July 11, 2019

Question:

I need a neutral to make 277v LED lights work. The city park poles have 3 phase 480v. I’m wondering if I can run a ground rod into the j boxes to ground the poles and drop a phase to use it as a neutral by hooking it up the the previous ground wires that go to the point of service. Is this allowed by the NEC?

Matthew Greb
A

Answer:

Hey Matthew thanks for your question. No, you can't make a Neutral Conductor out of a phase conductor. You don't mention if the 480 volt system is grounded or not. If it is, or if it can be, then possibly a neutral conductor can be extended from the grounding point to where you need it for the 277 volt LED lighting. If not, a transformer can be installed with a grounded secondary to provide a neutral conductor connection. See the definition of Neutral Conductor and Neutral Point in Article 100 for more information.

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