National Electrical Installation Standards

Standards as High as Your Own

Wednesday, April 25, 2018


Per NEC 690.12(2). If the PV module is rated at above 30 V and rated at 350 Watts, will it still be required to have "rapid shutdown" even though the distance of the inverter (which has disconnecting means) is less than 10 ft from the array to comply per NEC 690.12(2)? The PV system is on the roof?

Jessie Santos



Hey Jessie thanks for your question. Yes, rapid shutdown is required. Your reference is to the 2014 NEC and the 30 volts and 240-volt-ampere values are energy limitations within 10 seconds, not the module rating. Notice this section has significantly changed for the 2017 NEC with an array boundary of 1 foot being established. Outside the array boundary the 30-volt level remains but with a 30 second time limit and the volt ampere limitation has been deleted. Inside the array boundary requires listing or field labeling with an effective date of January 1, 2019.

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