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Technical Corner
For the article this month we will go over a portion of NEC code section 514 which is titled Motor Fuel Dispensing Facilities. We will evaluate NEC codes 2014, 2017 and 2020.
Specifically, let's look at section 514.11 (A) which discusses circuit disconnects. In the 2014 code cycle you will see the requirement:
So, to follow this the neutral must be disconnected as well as this is the grounded conductor. Most of the time there are various emergency pushbuttons strategically located which are used to interrupt power if there is a need to. To do this a single larger amperage contactor can remove power to an entire panel board or various smaller contactors for each fueling circuit can be provided. The emergency pushbutton operation essentially changes the state (removes power) of a larger amperage contactor or all the smaller amperage individual contactors.
Regarding this same section, it appears that in the NEC 2017 code cycle the requirement to disconnect the grounded conductor was removed. There is some speculation that the deletion of the requirement in the 2017 code cycle was unintentional. I’m not sure this is accurate information but the reasoning behind the deletion is unclear.
It would be code compliant under the 2017 code to not install a disconnect for the grounded conductor and in the 2020 cycle it appears that the requirement will be added back in. Also, please note that in the 2020 cycle it specifies that the equipment grounding conductors do not need to be disconnected.
Hopefully this article finds you well and can be used as a reference for your project needs. If anyone would like to contribute to the RES magazine and add an article or would like to request information on a specific topic (not limited to Electrical) just email me at beliasz@bergmannpc.com. As always, any comments are appreciated…!
Thank you for reading.
