National Electrical Installation Standards

Standards as High as Your Own

Thursday, March 12, 2020


I read the Code Questions and responses every day. My question is if an optional standby generator system is installed in a dwelling unit, is there supposed to be some means to identify that the generator is connected to the property. I'm concerned about any emergency response. I'm not an electrician but I was told there needs to be a sign installed. I appreciate any help provided.

Mark Simmons



Hi Mark, thanks for the comments and the question. Who ever told you that a sign was needed is on the right track. Since the system in question is an optional standby system, the information is located in Article 702 of the NEC titled "Optional Standby Systems." Section 702.7(A) indicates that a sign shall be placed at the service-entrance disconnecting means required in Section 230.85 and it must indicate each permanently installed on-site optional standby power source disconnect or means to shut down the prime mover of the generator. Hope this information is what you were seeking.

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