[RE-wrenches] Rapid shutdown questions

[Mac Lewis]

Hello wrenches,

I am still trying to wrap my head around how to comply with rapid shutdown
in off-grid and hybrid situations.  I've got a few questions that maybe you
can help with.

1.  What is a (currently listed) rapid shutdown system that will
accommodate 8 strings?  I know I can do this with Midnite combiners but as
I understand these aren't listed yet.
2.  On a remote pole mount, does rapid shutdown apply?  If the intent is to
isolate a safe zone around an array for fire fighting, it seems as though a
standard pole mounted DC disconnect can cover this concern.
3.  I estimate on a typical hybrid installation, rapid shutdown will cost
at least $3000 to implement. This includes remote shunt trip battery
breakers, contactors on PV side of charge controller and roof combiners,
and running control cable from remote disconnect to all locations.  As of
now, this would also require me to modify listed interconnection equipment.
 Is this what others are finding?
4.  AC coupling with microinverters may be the easiest way to comply with
most of these requirements.  However, this doesn't seem like a great
alternative to the standard charge controller installation in an off-grid
system.

Thanks in advance for your thoughts


-- 



Mac Lewis

*"Yo solo sé que no sé nada." -Sócrates*
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