It also seems like there should be some sort of wire marking to indicate functional grounding.  This code change makes sense, but it unleashes many new questions as well.  My vote is that is that PV is already current limited, so I don't see good reason to add fusing to the "functionally grounded conductor".

Ray Walters
Remote Solar
303 505-8760

On 6/15/20 3:24 PM, William Miller wrote:
Wrenches:

Well now that the NFPA has acknowledged that GFDI protected circuits do not solidly ground the “grounded“ conductor, and we know they can’t be white in color, it begs the next question:   Should these sort-of-grounded grounded  conductors be switched and over-current protected?

The manual for the Schneider charge controller shows the negative (or referenced) switched on one page and not switched on another.  Outback FM 100 manual shows the negative not switched.

Anyone have an argument either way?

William Miller
www.millersolar.com

On Jun 13, 2020, at 6:21 PM, Kent Osterberg <k...@coveoregon.com> wrote:

 James,

Here's the code reference: 2017 690.31(B)(1). Only solidly grounded PV system conductors shall be marked in accordance with 200.6 (white or gray).

Kent Osterberg
Blue Mountain Solar


On 6/13/2020 5:56 PM, James Jarvis wrote:
Brian, thank you very much. With your hint of "functional ground" I can clearly see that I am not allowed to have those be white wires.

Now time for me to incur the full wrath by daring to question the infinite wisdom of the "highly qualified individual" from the state.

(all kinds of fun stuff from this guy. Got another violation for having a donut type current transformer over a line voltage wire. He said that wasn't allowed.)

Thank you,

-James Jefferson Jarvis
APRS World, LLC
+1-507-454-2727

(Sent from my phone. My apologies for spelling errors and brevity.)

On Sat, Jun 13, 2020, 17:41 Brian Mehalic <br...@solarenergy.org <mailto:br...@solarenergy.org>> wrote:

    Change in 2017 to “functional grounded” was to clarify this -
    it’s not solid when it is thru a fuse or breaker than can be
    interrupted either in the event of a ground-fault or if the
    breaker is intentionally opened. 2017 makes it clear that there
    are very few solidly grounded systems (2 or less PV source
    circuits, not touching a building the only case it is allowed).
    Pardon any incorrect language as I don’t have my code book, but
    I do think the 2017 NEC® makes it very clear, including in the
    definition of function grounded, that those conductors cannot be
    white or gray, regardless of if the system has a
    transformer-based or TL inverter or a CC with integrated or an
    external GF breaker/fuse.

    Brian

    > On Jun 13, 2020, at 3:05 PM, greg egan
    <g...@remotepowerinc.com <mailto:g...@remotepowerinc.com>> wrote:
    >
    > Jim,  Hope all is well with you and yours.  on white wires in
    circuits, In 3 ph. circuits you can get killed breaking into a
    neutral that's common to other circuits.  One example, working
    on 277 lighting, you throw the breaker or light switch on the
    one circuit you're working so the hot isn't hot anymore.  It's
    standard practice for 3 ph. lighting ckts to share a neutral. 
    The white wire in your ckt is wire nutted in the j-box up in the
    ceiling to the common neutrals. Those neutrals are hot to ground
    when their respective ckts are hot and they're carrying current.
    >
    > Just thought it was worth mentioning on this list that there's
    no hard fast rule that all white wires are dead.  It depends on
    the ckt.
    >
    > Best,
    > Greg Egan
    > Remote Power Inc.
    >
    >
    > Message: 11
    > Date: Fri, 12 Jun 2020 15:17:19 -0500
    > From: James Jarvis<j...@aprsworld.com <mailto:j...@aprsworld.com>>
    > To: RE-wrenches<re-wrenches@lists.re-wrenches.org
    <mailto:re-wrenches@lists.re-wrenches.org>>
    > Subject: [RE-wrenches] White wire for DC- after ground fault
    breaker
    > Message-ID:
    >   
    <CAFWEuYVMACXebixHtyRVYQ5Xnmaur=ugtv6etu5tnepm00n...@mail.gmail.com
    <mailto:ugtv6etu5tnepm00n...@mail.gmail.com>>
    > Content-Type: text/plain; charset="utf-8"
    >
    > Hello Wrenches,
    >
    > I have an off-grid install where I was recently red-tagged by
    the state
    > inspector. System is 24 volt with battery, Magnum inverters,
    some Magnum
    > charge controllers, and a Morningstar charge controller. It is
    permitted
    > under NEC 2017.
    >
    > One of the inspectors issues was that my DC- conductors to the
    array /
    > rapid shut down box are black color. He wants them to be white
    because he
    > says they are solidly grounded. I reason that they are only
    solidly
    > grounded when they are solidly grounded. As soon as the ground
    fault
    > protection breaker opens, they are floating at array voltage.
    I think it is
    > misleading and unsafe to have a white conductor that can have
    hundreds of
    > volts of potential on it when a breaker trips.
    >
    > I haven't dug into the code yet. I'm just working on the logic
    that one of
    > my mentors put into me which is white wires better not have
    voltage
    > potential on them. "That's the sort of sh*t that kills
    electricians" is
    > what he repeatedly said ... and it's stuck with me.
    >
    > Thoughts? I'm backed into the corner with the state, so I will
    be changing
    > them to white even if it is unsafe ... unless I have some code
    backing.
    >
    > <rant>Changing the wires to white will get interesting up on
    the roof. I
    > wonder if they want me to cut off the black MC on the modules
    and replace
    > them with white? This is mostly just an exercise in the State
    of Minnesota
    > only wanting to know about and allow micro inverters. They
    brought in a
    > state inspector from three hours away who kept repeating that
    he was a
    > "highly qualified individual", but was unable to identify or
    recognize a
    > charge controller. He kept referring to the charge controllers as
    > inverters.</rant off>
    >
    > Thanks,
    >
    > -James Jarvis
    > APRS World, LLC
    > +1-507-454-2727
    > http://www.aprsworld.com/
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