National Electrical Installation Standards

Standards as High as Your Own

 
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Friday, March 2, 2018

Question:

Charlie, Thank you for all of your great work to help the electrical industry.

My question concerns a 60 amp, three pole, four wire power receptacle that has been factory built into a fused disconnect switch. Typically, these receptacles and switches are rated at 600V.  Am I prohibited from using one of these receptacle / fused disconnect assemblies in a 240V, three pole, four wire application?

Thank you, Robert Frye, PE

A

Answer:

Hey Robert thanks for your question and the compliment. Electrical equipment must be rated for at least the nominal circuit voltage as stated in 110.4. Receptacles connected to circuits with different characterizes (such as different nominal voltages) must be designed to be noninterchangeable, on the same premises as stated in 406.4(F). So unless the listing instructions prohibit it and you are not using the same receptacle configuration for a different voltage the 600 volt switch/receptacle combination is allowed to be used for a 240 volt application.

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