[RE-wrenches] Buchanan Crimp in 1000v Applications and the NEC

Wed Nov 12 12:25:47 PST 2025

Wrenches,
Wow have we all gone done the rabbit hole here, not all NEMA 3 can can be
mounted in any position other that upright with entre points only from
below, laying a box neatly flat on the rail may not have any drains where
needed, also make sure the mounting holes are sealed.
Some inspectors want the box under a panel and some require it exposed.
In Hawaii l had inspectors require MC-4 at every wire connection not
including grounds everywhere and yes we complied.
Easier to comply than fight sometimes because there is always a next time
Fun times

On Wed, Nov 12, 2025, 11:25 AM Brian Mehalic via RE-wrenches <
re-wrenches at lists.re-wrenches.org> wrote:

> Well this isn’t a totally direct answer to questions on this thread, but I
> did want to address wet locations. (I do think the text on the Buchanan
> spec sheet in regards to voltage makes it a no-go for 1kV+ systems. It's a
> little surprising "fixture" isn't defined in the NEC, though in that case
> the convention is to use the generally accepted definition, which matches
> the contextual usage in the NEC - a permanently installed light, not
> including the bulb).
>
>
> As defined in the NEC (2026), a rooftop is (no duh, even here in Arizona!)
> a wet location:
>
>
> Location, Wet. (Wet Location)
>
> A location that is one or more of the following:
>
> (1) Unprotected and exposed to weather
>
> (2) Subject to saturation with water or other liquids
>
> (3) Underground
>
> (4) In concrete slabs or masonry in direct contact with the earth
>
>
> The inside of raceways in wet locations above grade is also a wet location:
>
>
> 300.11(A) Raceways in Wet Locations Above Grade.
>
> Where raceways are installed in wet locations above grade, the interior of
> these raceways shall be considered to be a wet location. Insulated
> conductors and cables installed in raceways in wet locations above grade
> shall comply with 310.10(C). [310.10(C) is requirements for conductors in
> wet locations]
>
>
> 314.14 requires junction boxes used in damp or wet locations have to be
> listed for such use, as is the case with 3R (which can be marked
> “rainproof”) and 4X (which can be marked “watertight”) enclosures (note the
> minimum drainage opening size in (C)(1), so as to prevent clogging), but
> does not state that their interior is considered a wet location:
>
>
> 314.15(A) Prevent Moisture.
>
> In damp or wet locations, boxes, conduit bodies, outlet box hoods, and
> fittings shall be placed or equipped to prevent moisture from entering or
> accumulating within the boxes, conduit bodies, or fittings.
>
> 314.15(B) Listed.
>
> Boxes, conduit bodies, outlet box hoods, and fittings installed in wet
> locations shall be listed for use in wet locations.
>
> 314.15(C) Drainage.
>
> 314.15(C)(1) Approved Openings.
>
> Approved drainage openings not smaller than 3 mm (1∕ 8 in.) and not larger
> than 6 mm (1∕ 4 in.) in diameter shall be permitted in the field in boxes
> or conduit bodies listed for use in damp or wet locations.
>
>
> Enclosures for OCPDs (240.32) in damp or wet locations, and panelboards
> (408.37) in damp or wet locations must comply with 312.4(A) and (B):
>
> 312.4(A) Weatherproof Enclosures.
>
> In damp or wet locations, surface-type enclosures within the scope of this
> article shall be placed or equipped such that moisture or water is
> prevented from entering and accumulating within cabinets or cutout boxes,
> and be mounted so there is at least 6 mm (1∕ 4 in.) of airspace between
> enclosures and walls or other supporting surface (yikes!!!!). Enclosures
> installed in wet locations shall be weatherproof. Exception: Nonmetallic
> enclosures shall be permitted without the airspace on a concrete, masonry,
> tile, or similar surface.
>
> 312.4(B) Raceways or Cable Above Live Parts.
>
> For enclosures in wet locations, raceways or cables entering above the
> level of uninsulated live parts shall use fittings listed for wet locations.
>
> The OCPDs installed in a typical panelboard are listed and designed to be
> installed in that enclosure, which has the proper rating for the location;
> and additional requirements stated above prevent direct dripping of
> moisture onto energized components such as bussing or breakers.
>
> The only requirement related to listing for connections in 110.14 is that
> direct buried connectors or splicing means be listed for such use.
>
> 110.11 states, in regard to deteriorating agents, conductors or equipment
> located in damp or wet locations must be identified for use in the
> operating environment. Note the definition of identified, and that listing
> is one means of identification but not the only one, so there is some
> latitude for the AHJ:
>
> Identified (as applied to equipment).
>
> Recognizable as suitable for the specific purpose, function, use,
> environment, application, and so forth, where described in a particular
> code requirement.
>
> Brian Mehalic
> Solar Tech Collective
> National Electrical Code® CMP-4 Member
> (520) 204-6639
>
>
>
> On Tue, Nov 11, 2025 at 8:03 PM Glenn via RE-wrenches <
> re-wrenches at lists.re-wrenches.org> wrote:
>
>> Having opened and inspected dozens of rooftop installations, I can firmly
>> say that anything inside a box of any kind on a rooftop will absolutely be
>> exposed to moisture and often water. Whether it is humidity sucked in from
>> thermal cycling, or gasket failure through UV degradation, or here in the
>> north, snow and ice damage, it will happen.
>>
>> You will never convince me that it is acceptable to use any device there
>> that does not have a published, traceable listing for outdoor use in that
>> environment.
>>
>> -Glenn
>>
>> On Nov 11, 2025 19:30, Jason Szumlanski <
>> jason at floridasolardesigngroup.com> wrote:
>>
>> We're talking about inside a junction box (NEMA 3R or 4, for example),
>> not an "outdoor environment." Wagos (and other connectors like wire nuts,
>> Polaris Taps, power distribution blocks, terminal blocks, etc) are allowed
>> inside of a rooftop junction box, just like they are allowed in various
>> switch boxes, enclosures, and cabinets that are suitable for the
>> environment outdoors.
>>
>> For the same reason you can put circuit breakers inside of a NEMA 3R load
>> center outdoors, you can use splice connectors of many kinds inside of a
>> NEMA 3R enclosure. They do not need to be listed for "outdoors" because it
>> is not outdoors. It's enclosed and adequately protected from the
>> environment.
>>
>> In other words, any AHJ that challenges me on this, I just ask them to
>> show me a circuit breaker that's listed for use in a wet location. That's
>> usually enough to shut them down.
>>
>>
>> Jason Szumlanski
>> Principal Solar Designer | Florida Solar Design Group
>> NABCEP Certified Solar Professional (PVIP)
>> Florida State Certified Solar Contractor CVC56956
>> Florida Certified Electrical Contractor EC13013208
>>
>> On Tue, Nov 11, 2025, 7:11 PM Glenn <glenn.burt at glbcc.com> wrote:
>>
>> I have not found a listing for Wagos in an outdoor environment.
>>
>> -Glenn
>>
>> On Nov 11, 2025 18:01, Jason Szumlanski via RE-wrenches <
>> re-wrenches at lists.re-wrenches.org> wrote:
>>
>> We have had terrific success using Wagos in rooftop junction boxes for
>> splicing #12 Enphase cable to #10 home run THWN. We have no issues
>> whatsoever with these.
>>
>> Unfortunately, the #10 PV wire insulation is too large for the Wago
>> 221-6XX series. We have been buying #14-#4 Polaris taps and it's getting
>> very expensive. I would like an alternative.
>>
>> For a while we were using the King Innovation AlumiConn purple "suitcase"
>> connectors for Enphase, but they are only 300V rated and I don't think the
>> PV Wire insulation fits in those, either, for <300V applications.
>>
>> I have seen people using MC4 connectors in rooftop junction boxes like
>> Blake suggested, but I wasn't sure if that is acceptable practice to use
>> them this way (in an enclosure), and it does require a pretty large
>> junction box. We prefer to use the EZ Solar JB-# series of boxes. The rail
>> mount ones (JB-3) are pretty small, but the tile roof JB-2 is huge, and the
>> shingle JB-1 is sizable as well. I guess if there is no prohibition against
>> using them in an enclosure, then it should be allowed. I do like the
>> watertight nature of this solution.
>>
>> I have seen some clowns using MC4 connectors with #10 THHN wire to make
>> these splices. That's obviously no bueno. Crazy stuff...
>>
>>
>> Jason Szumlanski
>> Principal Solar Designer | Florida Solar Design Group
>> NABCEP Certified Solar Professional (PVIP)
>> Florida State Certified Solar Contractor CVC56956
>> Florida Certified Electrical Contractor EC13013208
>>
>>
>> On Tue, Nov 11, 2025 at 4:44 PM Dave Tedeyan via RE-wrenches <
>> re-wrenches at lists.re-wrenches.org> wrote:
>>
>> Hi Adam,
>> This response is just to you. Is NYSERDA the inspection agency you are
>> talking about? Cause they have given me issues about using Wago Nuts inside
>> a 3R box, even after I got a statement from Wago saying that it is okay to
>> put it inside a 3R box. But squirting a bit of No-Ox in there seems to make
>> them happy about it. The one time we put one inside a 3R panel board to
>> extend a short wire and forgot to put No-Ox on that one, they gave us a 2
>> out of 5 on the inspection, even though that was the only thing noted in
>> the entire inspection report! But I would be curious if the point you make
>> above will work with NYSERDA?
>>
>> Cheers,
>> Dave
>>
>> On Tue, Nov 11, 2025 at 4:16 PM AE Solar via RE-wrenches <
>> re-wrenches at lists.re-wrenches.org> wrote:
>>
>> We had an inspection agency that was giving us a hard time about using
>> buchanan crimps in junction boxes because they aren't rated for
>> outdoor/damp locations. The point was made (on this listserve) that "*if
>> the inside of a 3R enclosure isn't considered dry enough for a buchanan
>> crimp/cap, then there's millions of 3R panels with breakers and busbars in
>> them that would have the same problem*". The inspection agency finally
>> relented. We put a little No-Alox in the cap. I know that's not what your
>> initial post was about, but tossing that in for consideration just in
>> case...
>>
>> Adam Katzman (he/him)
>> Autonomous Energies | Owner/Operator
>> www.AutonomousEnergies.com <http://www.autonomousenergies.com>
>> (518) 567-1468
>>
>>
>>
>>
>> On Tue, Nov 11, 2025 at 3:51 PM Jay via RE-wrenches <
>> re-wrenches at lists.re-wrenches.org> wrote:
>>
>> Hi Sam
>>
>> I can’t imagine being just copper it would matter, the AHJ might have a
>> different opinion however
>>
>> Question.
>> How are you insulating them?
>>
>> Jay
>>
>>
>> On Nov 11, 2025, at 11:15 AM, Sam Haraldson via RE-wrenches <
>> re-wrenches at lists.re-wrenches.org> wrote:
>>
>> 
>> Wrenches,
>>
>> On the attached product spec sheet for Ideal Copper Crimps (aka Buchanan
>> crimps) you'll see that max voltage for the crimp is rated at 600V but an
>> asterisk indicates up to 1000V when "in fixtures and signs".  In our
>> application this is a 1000v system and we are joining pairs of #10 PV
>> wires.  The junctions are made in a rail-mounted, plastic j-box.  We could
>> not find the definition of "fixture" as it might pertain to this situation
>> in the NEC and as such are interested to learn more about using Buchanan
>> crimps for 1000V applications.
>>
>> <image.png>
>>
>>
>> Cheers,
>> Sam
>>
>> [image: OnSite Energy] <https://onsiteenergyinc.com/>
>>
>> Sam Haraldson
>> Operations Specialist
>> (406) 551-6135
>> 1515 N. Rouse Ave Bozeman, MT 59715
>> <https://www.google.com/maps/search/1515+N.+Rouse+Ave+Bozeman,+MT+59715?entry=gmail&source=g>
>> Locally owned and operated since 2012
>> [image: B Corporation] <https://onsiteenergyinc.com/bcorp>
>> <IDEALIndustries-Crimp Connectors.pdf>
>> _______________________________________________
>> List sponsored by Redwood Alliance
>>
>> Pay optional member dues here: http://re-wrenches.org
>>
>> List Address: RE-wrenches at lists.re-wrenches.org
>>
>> 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/re-wrenches@lists.re-wrenches.org/
>> 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
>>
>> _______________________________________________
>> List sponsored by Redwood Alliance
>>
>> Pay optional member dues here: http://re-wrenches.org
>>
>> List Address: RE-wrenches at lists.re-wrenches.org
>>
>> 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/re-wrenches@lists.re-wrenches.org/
>> 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
>>
>> _______________________________________________
>> List sponsored by Redwood Alliance
>>
>> Pay optional member dues here: http://re-wrenches.org
>>
>> List Address: RE-wrenches at lists.re-wrenches.org
>>
>> 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/re-wrenches@lists.re-wrenches.org/
>> 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
>>
>> _______________________________________________
>> List sponsored by Redwood Alliance
>>
>> Pay optional member dues here: http://re-wrenches.org
>>
>> List Address: RE-wrenches at lists.re-wrenches.org
>>
>> 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/re-wrenches@lists.re-wrenches.org/
>> 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
>>
>>
>>
>> _______________________________________________
>> List sponsored by Redwood Alliance
>>
>> Pay optional member dues here: http://re-wrenches.org
>>
>> List Address: RE-wrenches at lists.re-wrenches.org
>>
>> 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/re-wrenches@lists.re-wrenches.org/
>> 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
>>
>> _______________________________________________
> List sponsored by Redwood Alliance
>
> Pay optional member dues here: http://re-wrenches.org
>
> List Address: RE-wrenches at lists.re-wrenches.org
>
> 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/re-wrenches@lists.re-wrenches.org/
> 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
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20251112/327906f2/attachment.htm>