O.k. the layout has (14) arrays and combiner boxes coming down from the rooftop into a room on a lower level where the inverter is located. The inverter has an internal DC disconnect with a handle that is external to the cabinet. From what I gather out of NEC 690 section III is that the disconnct internal to the inverter is all that is required to disconnect the PV system wiring from all other conductors in the building structure. This means that there does not have to be a DC disconnect at each combiner box although sometime I know they are put there fore convenience.
Don't forget that if your inverter is tied into any of the structure's utility or other power source's AC system, you need an AC disconnecting means, too.
The only question I have about the inverter disconnect is 690.14(1) which states the disconnect should be at the nearest point of entrance of the PV system conductors. In my case the conductors enter the building from the roof but may have to travel inside the parking garage for a little bit before they get to the inverter on the lower level. Is there a maximum distance that the circuits can run inside before they must hit a disconnect. (Nearest can be loosely defined as written in the code)
Since subject to interpretation, mounting outside or immediately inside is always the non-debatable option... but its equal is asking the AHJ and knowing beforehand if an inside location beyond immediate is acceptable. Two disconnecting means may be required because of your inverter's location and routing of supply conductors.
Aso what is meat in 690.16(A) regarding fuses? Does this simply mean that each PV source circuit should be capable of being independently disconnected from the other source circuits, thus the purpose of the fuses in the combiner box? What about section (B) for fuse servicing?
Simply put, any fuse in the PV system must have zero voltage when accessible by other than qualified personnel. The key words in this requirement are "accessible" and "qualified". A locked fuse box (e.g. fused combiner) would limit access, but assuring a person accessing the locked box is qualified is always open to debate :roll::roll::roll: Perhaps a "qualified personnel only" label would be acceptable the AHJ... either that or a disconnect on both sides of the fuse(s).