National Electrical Installation Standards

Standards as High as Your Own

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Friday, January 11, 2019

Question:

On a 100 temporary service is the neutral required to be insulated? I have been using SEU cable but the inspector red tagged. His comment was if I could show him in the code book if the neutral was not required to be insulated he would ok the service

Alfred Boggess

A

Answer:

Hey Alfred thanks for your question. The general rule is for service entrance conductors to be insulated as stated in 230.41. The exception allows grounded conductors to be uninsulated such as bare copper in list item (1) if part of a service cable assembly and aluminum, without insulation or covering, in list item (4) if part of a cable assembly. SEU cable is commonly used for this purpose. Usually it is the AHJ's responsibility to cite the section that is being violated but at least you inspector is open to reason.

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