Hint: A through-the-wall cord connection.
If you look closely at this photo, you should be able to see the power supply cord passing right through the brick wall of the building. Where does this cord go? Is it spliced in an outlet box inside the building? Is it plugged into a receptacle somewhere? I wish I knew the answers to those questions.
While Sec. 400.10(A)(2) does give permission to use flexible cords and flexible cables for wiring of luminaires, Sec. 400.12 places restrictions on what we can and cannot do with flexible cords, flexible cables, cord sets, and power supply cords. Section 400.12(2) prohibits their installation where run through holes in walls, floors, or ceilings. Section 400.12(5) prohibits their use where concealed by walls, floors, or ceilings. And Sec. 400.12(1) prohibits them from being used as a substitute for the fixed wiring of a structure.
