[RE-wrenches] Battery RSD

[Zeke Yewdall]

I've been mostly using batteries that have a built in circuit breaker on
them, so haven't run into this exactly.  But those circuit breakers are
inside of the garage or utility room, not accessible from the exterior of
the house.  Of course, our typical lead acid batteries never had any
disconnecting means built into them, so the disconnect was always at the
inverter wiring panel... and except in cases of a wall between the
batteries and the inverter, we never had to have a disconnect at the
battery.

My understanding of the code, 706.15 (B) allows a remotely controlled ESS
disconnect -- the kill switch that turns the inverter off from the outside
of the house (right next to, or even the same button as the PV array RSD).

706.(E)(1) seems to imply that the battery breaker in the inverter should
be sufficient if it's within sight of the batteries.

706.15 (E) (3) does allow a remote controlled battery disconnect as well.
But it's not clear whether that is accomplished by turning off the inverter
remotely, or if you need a remote trip breaker?    The ESS disconnect in
706.15(B) that cuts power to the house is not necessarily the same thing as
the battery disconnect required in 706.15 (E).  Most inspectors seem to be
concerned about cutting power to the house, which is (B)... not necessarily
the inner workings of the PV system (which is (E).

If putting a knife blade type switch, you would actually need a 200A rated
one (at least.... technically a 12kW inverter like that needs a 250A
rating, which means going to a 400A disconnect.... that's going to be a
monster of a switch).  Unless you can get a field listing to parallel the
three poles of a 100A DC disco for 300A rating.  Manufacturers can do that,
but not sure field wiring them in parallel would fly.
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