In dwellings, battery cells for PV systems must be connected so as to operate at _____, nominal, or less.
See answer and applicable Code reference
The correct answer is: d) 50V
The provisions of Art. 690 apply to solar PV systems, including the array circuit(s), inverter(s), and controller(s) supporting such systems. Part VIII of this Article focuses on storage batteries. As noted in Sec. 690.71(B)(1), "Storage batteries for dwellings shall have the cells connected so as to operate at a voltage of 50V, nominal, or less."