Well... just looking this over again, I guess I can see how the NEC could cause some confusion.
For branch circuit load calcs, 220.14[f] states that sign and outline lighting outlets shall be calculated at a minimum of 1200VA for each required branch circuit specified in 600.5[a].
If it’s 120V, that’s only 10A for the entire circuit?
Then 600.5[a] on the other hand, appears to be written in the singular, even beginning with "Required Branch Circuit".
Seems like there also should be at least some mention in there that sign lighting should be considered a continuous load.
Couldn’t someone wiring a commercial building with several public entrances and unknown future occupancy or signage, read that 600.5[a] requires only one branch circuit with a minimum 20A rating and no other outlets for all sign outlets for each of these entrances?
If the specs called for several outlets at each entrance for future sign use, couldn’t that lead to a situation with many sign outlets of unknown maximum wattage on this one branch circuit? How do you know that the load won’t be over 16A on a 120V circuit?
This seems like it would leave a lot up to the discretion of the person doing the wiring.
