[RE-wrenches] PV Array Definition and 690.47(D) (2008)

[Jason Szumlanski]

The definition of Array in 690.2 is ambiguous. Figure 690.1(A) seems to
indicate that groups of modules on different roof surfaces could be
considered a single array. The textual definition itself could be construed
either way. We have successfully argued that an entire roof mounted system
with modules on different roofs constitutes a single array. Therefore, if
the additional grounding electrode required by 690.47(D) qualifies for
Exception 2, it is not required. However, our "favorite" jurisdiction has
just interpreted it differently, requiring a separate electrode and
electrode conductor for each roof surface... and there are a lot of roof
surfaces on this particular job. Complying will not be fun or cheap.

How is your jurisdiction interpreting this?


Related note: Figure 690.1(A) would effectively make each module in a
microinverter based system a distinct array. The figure seems to imply that
all modules that form a PV Output Circuit are a single array. Each module
is a complete PV Output Circuit in a microinverter based system. It's
strange that the textual definition is concerned with mechanical
assemblies, but the figure refers to electrical configuration in defining
Array. In fact, in the text an Array is defined as components forming "a
direct-current power-producing unit." In a microinverter-based system, how
can any group of modules be considered an array given that definition?


Jason Szumlanski

Fafco Solar
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20140929/714c275d/attachment-0001.html>