Hi William - I think this article by Bill Brooks directly answers both of your questions:
https://www.southportland.org/files/8814/8156/0204/NEC_2017_Updates_for_PV_Systems___SolarPro_Magazine.pdf -August On Thu, Sep 16, 2021 at 9:19 AM William Miller <[email protected]> wrote: > Friends: > > > > Thanks to all of you for your valuable input on the repowering project I > am researching. I am learning a lot in the process and generating more > questions as I proceed. Here is are questions that came up, and if any of > you have insight, I would love to hear it: > > > > 1. Array OCPD/disconnecting. The existing array has fuses in the > positive leads only. If we were to upgrade to transformerless inverters, > will we be required to install OCPD in the negative leads as well? (In > researching this I came upon this entry in 2017 NEC 690.9: *Informational > Note: Due to improved ground-fault protection required in PV systems by > 690.41(B), a single overcurrent protective device in either the positive or > negative conductors of a PV system in combination with this ground-fault > protection provides adequate overcurrent protection.*) > > *2. *In the 2014 NEC when installing Ungrounded PV systems, the > following requirement appeared in 690.35: *Conductors listed and > identified as PV wire installed as exposed, single conductors…* What > happened to 690.35, and can I now use USE-2 on transformerless inverter > installations? > > > > Thanks in advance. > > > > William Miller > > > > Miller Solar > > 17395 Oak Road, Atascadero, CA 93422 > > 805-438-5600 > > www.millersolar.com > > CA Lic. 773985 > > > > > _______________________________________________ > List sponsored by Redwood Alliance > > Pay optional member dues here: http://re-wrenches.org > > List Address: [email protected] > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > There are two list archives for searching. When one doesn't work, try the > other: > https://www.mail-archive.com/[email protected]/ > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > > List rules & etiquette: > http://www.re-wrenches.org/etiquette.htm > > Check out or update participant bios: > http://www.members.re-wrenches.org > >
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