NEC Definitions


Anybody know how the 2017 NEC defines ground-mounted systems? My understanding is that it's considered a structure and not a building. But I'm not finding much on it.

I'm trying to determine the need for raceway labels, (690.31(G) is what I'm referencing). I don't have the code but from what it sounds like; raceway labels apply to all PV System DC circuits on or in a building. But if there is a distinction by the NEC between a "structure" and a "building", and a ground-mounted system is a "structure", like a solar farm for example, then raceway doesn't require labeling.

The labeling I'm referencing reads :"WARNING: PHOTOVOLTAIC POWER SOURCE".

Any clarification is greatly appreciated!!



  • Tecnodave
    Tecnodave Registered Users Posts: 437 ✭✭✭✭

    A ground mount is a "structure" way looser code set than a "building" which is meant to be "occupied", not sure on the labeling though! The warning label you mention is required on a building so that firefighters know to look for the solar shut down system. There are also special labeling if a building has more than one power source , not normally allowed but not uncommon in industry to have both 480 and 240 in legacy systems, new construction it's not allowed. Same reasoning. Safety for first responders. Signs at all power sources. If your solar shutoff is not next to the main panel you will probably have to label every power source to the building.

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