The directions for Enphase micro-inverters call it a
Branch Circuit many times in the paperwork included with the product.
I see it as a 2-way circuit...its an
Inverter Output Circuit going towards the utility supply and a
Branch Circuit going towards the Inverter. And in the direction from utility to inverter the circuit is a Branch Circuit and subject to the rules as applied for branch circuits.
So look at the specs here...
http://www.enphase.com/sites/default/files/M215_DS_EN_60Hz.pdf
See how the nighttime power consumption is "65mW max"...well that makes the micro-inverter an
Outlet by definition in the Code.
Actually, all inverters use some power at nighttime and should be considered an
Outlet and
Utilization Equipment by the Code, I do.
shortcircuit