Re: [RE-wrenches] Temperature coefficient versus Power

Hi Jason, That's an interesting question, as typically it is stated that temperature coefficients are linear, however the "linearity" is with respect to the temperature variable, not power (irradiance) I have always assumed that tkPmp is fairly linear with respect to power, but now that you

Re: [RE-wrenches] Head scratcher

Also, it's unlikely in a tiny home, but double-check there are no multiwire branch circuits. Neutral could be overloaded once L1 and L2 are the same. There is a required label that states this in Article 710.15(C). On Tue, Oct 18, 2022, 5:09 PM Vince McClellan via RE-wrenches <

Re: [RE-wrenches] wire management on Qcell AC module

Please note we updated 2020 NEC 690.31(C)(1) to allow 24" between securing/supporting points for PV cable, and removed the problematic reference to 334.30. The change was made because as you all know there is not always a way to secure wires within 12" of a box on the back of a PV module. Of

Re: [RE-wrenches] Plumbing/Mechanical Code for obstructions above plumbing vents

Note that CA adopts UPC not IPC and the last time I checked there was no exception to allow shorter vents under solar panels in the UPC, so it differed from IPC allowance. If this has changed, would be glad to be know about it! Cheers, Rebekah On Fri, May 13, 2022, 10:51 AM Brian Mehalic via

Re: [RE-wrenches] Aurora solar design software?

ectric Systems Sales & Service802-272-0004* > > > On Wed, Jan 5, 2022 at 12:01 PM Rebekah Hren > wrote: > >> Hi all, >> Are there any other wrenches out there using aurorasolar.com? I have >> been using it about a year and have found it awesome. Awesome that is until >

[RE-wrenches] Aurora solar design software?

Hi all, Are there any other wrenches out there using aurorasolar.com? I have been using it about a year and have found it awesome. Awesome that is until the newest update came out and basically destroyed the utility for me. I'm wondering if I am over-reacting and I'll get used to the new update

Re: [RE-wrenches] Enphase Enpower Smart Switch as service disconnect

I don't see why not, I have one I'm experimenting with in my garage now and it passes power through the bus prior to commissioning. I would make sure to add the Eaton BR main breaker in the Enpower at whatever amperage required for a more trustworthy discontent than the relay manual switch. It

Re: [RE-wrenches] Snap-n-rack bonding certification

ghtly less of a pain. Rebekah Tel: 336.266.8800 On Tue, Jul 20, 2021 at 4:37 PM Rebekah Hren wrote: > Hi William > > Groan, I don't see that precise model in the series 100 installation > manual > <https://snapnrack.com/wp-content/uploads/2019/05/S100-UL-Install-Manual_v2.0_

Re: [RE-wrenches] Snap-n-rack bonding certification

Hi William Groan, I don't see that precise model in the series 100 installation manual on pg 74 which is the bonding evaluation list of modules I hope for your sake Snapnrack will send an email the AHJ will

Re: [RE-wrenches] Utitlity Rate question

Hi William, Thanks for posting the links to your studies. With CA NEM. 2.0 customers forced into TOU rate schedule, I have been wondering if you have done an analysis on whether TOU-C (peak 4-9 everyday) or TOU-D (peak 5-8 weekdays) is a better pair with solar?

Re: [RE-wrenches] solar scrim

Does not require listing, though it may be listed as part of racking assembly by manufacturer. If made of metal you are going to run into more questions from AHJ regarding bonding, thus I would recommend plastic. Rebekah On Sat, Jan 23, 2021, 10:38 AM Jerry Shafer wrote: > I have, price point

Re: [RE-wrenches] Cable Tray Marking

This is interesting, since the definition of high voltage was changed to >1000V a few code cycles ago and it is somewhat consistently applied throughout the NEC at that voltage (except for workspace clearances...er). It seems this 392.18 label requirement could cause confusion and should be

Re: [RE-wrenches] NEC in PDF format not availaible for 2020

NFPA does make its Codes and Standards available for free online: https://www.nfpa.org/Codes-and-Standards/All-Codes-and-Standards/Free-access?order_src=C900=EAIaIQobChMIqfz4itz-5gIVFarsCh3elQ5UEAAYASAAEgKQ5_D_BwE As does the ICC: https://codes.iccsafe.org/category/I-Codes However, I too am

[RE-wrenches] Fire sprinkler expert?

ation consultant they could recommend to me? Thanks! Rebekah Hren ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wre

Re: [RE-wrenches] MiaSolé thin film flexible solar panel

I'm really curious about this product and company as well - looks like they sell mostly in China? They have a lot of open positions on their website, and a range of products, but??? Thanks! Rebekah Hren Tel: 336.266.8800 On Mon, May 6, 2019 at 6:16 AM Tump wrote: > Does anyone h

Re: [RE-wrenches] Recording Volt Meter

The Hioki meter amazes me. It can measure up to 1500VDC, and bluetooth communications to a really simple to use phone app that records single or multiple channels up to 24 hrs, and exports to pdf, it's totally intuitive to use. See pg 34 in the manual.

Re: [RE-wrenches] Multiple inverters

separate in your mind, I think it helps - although of course the inverter AC disconnect for a string inverter will often also be serving as the system disconnect, so there is a lot of overlap. On Mon, Feb 25, 2019 at 5:39 PM Rebekah Hren wrote: > Hi Chris and William > There was cer

Re: [RE-wrenches] Multiple inverters

Hi Chris and William There was certainly no intention to mandate that all inverters connect to one OCPD/disconnect.But 705.12(B)(1) in 2017 clarifies that systems like Enphase could have multiple inverters on one breaker, certainly not that all inverters in a building have to be on breaker.

Re: [RE-wrenches] Off-grid refrigerator

I know this isn't what Will is looking for, but just in case anyone still needs a 12/24vdc model frig, I got an ARB 60 qt at the beginning of the summer, and it's been a champ. Especially for mobile applications, it doesn't need to be level. http://store.arbusa.com/Fridges-C11.aspx Temp setable

Re: [RE-wrenches] Rapid Shutdown Again?

Hey Evan, if you click on first draft report instead of submit comments you will find it. On Thu, Aug 30, 2018 at 11:03 AM Evan M wrote: > Curious if there's any way to view the 2020 draft with the gray > highlighted proposed changes formatting typical of published final versions > of the Code.

[RE-wrenches] JLM Phazr

Hi Wrenches, Does anyone know if JLM is still around/ products available? https://www.greentechmedia.com/articles/read/jlm-energy-lays-off-workforce-to-seek-funding It sounds like

Re: [RE-wrenches] Rapid Shutdown Again?

he NEC is standardized by the NFPA and while it may not be perfect, it's what we've got! Best, Rebekah Hren On Tue, Aug 28, 2018 at 6:50 AM cwarfel wrote: > I like your solutions to this. Just sticking to rapid shutdown and not > the fire code, I think a lot of the problems with 690.12 coul

Re: [RE-wrenches] Fwd: Re: Rapid Shutdown and January 1 2019 option?

18 at 4:39 PM Ray wrote: > > > > Forwarded Message > Subject: Re: [RE-wrenches] Rapid Shutdown and January 1 2019 option? > Date: Fri, 6 Jul 2018 16:37:47 -0600 > From: Ray > To: Rebekah Hren > > Hi Rebekah; > > I very much appreciated your

Re: [RE-wrenches] Rapid Shutdown and January 1 2019 option?

t your comments submitted! Rebekah Hren Member, NEC CMP-4 On Fri, Jul 6, 2018 at 2:22 PM Dan Fink wrote: > I agree with you, Ray, as a purely off-grid solar installer and > troubleshooter. I think all that was accomplished in NEC 2017 on this issue > is that non-habitable structures, like

Re: [RE-wrenches] Location of DC disconnect vis-a-vis rapid shutdown exemption

en with all the changes made in 2017, it seems that we still are left > with too much uncertainty about where a PV circuit ends, or what > constitutes the "PV Disconnect" in an off grid system. Not such a big > deal, until we are required to apply 690.12. > > Thanks everyone fo

Re: [RE-wrenches] Location of DC disconnect vis-a-vis rapid shutdown exemption

perimeter of the array in the 2017 NEC, so the inverter must be positioned within one foot of the array if there is not going to be any other RS equipment. The PV system disconnect (backfed breaker) or the service disconnect can serve as the rapid shutdown initiation device in that case. Best, Rebekah Hr

Re: [RE-wrenches] Clearance clarification please

Free access to the I-Codes is available here: https://codes.iccsafe.org/public/collections/I-Codes See IRC R324.6.1 for pathways Rebekah Hren On Tue, Apr 3, 2018 at 2:10 PM, Brian Mehalic <br...@solarenergy.org> wrote: > Access pathways and clearances are in the International

Re: [RE-wrenches] Off grid in Florida

I gotta say here that utilities don't control construction permits or C.O.s, rather it is the local jurisdictional authority. So the idea that FPL is somehow mandating grid-connection for all construction seems preposterous to me. It is up to the individual AHJs, and the NEC has clear requirements

Re: [RE-wrenches] Well pump grounding question

Maybe I should clarify here that the wire type switches at the well head, and that is the point at which the metal well casing is bonded to the EGC running with the current carrying conductors to the supply circuit 20A breaker. On Wed, Apr 26, 2017 at 7:09 PM, Rebekah Hren <rebekah.h...@gmail.

[RE-wrenches] Well pump grounding question

Hey everyone, I'm replacing my old DC 24V shurflo well pump with a new Grundfos 15 SQ05-110. It's the 120V AC model. Question: The Shurflo required 2 wire cable with no ground, the Grundfos has black/white/green. Can anyone think of a good reason why I should replace 100' of expensive

Re: [RE-wrenches] Tesla 2.0

I have the same questions as Jay, I would really like to see the real specs for the Tesla 2.0. Other questions I have: -How will the Tesla 2.0 be installed in coordination with a PV system - I can only assume any PV system would have to be AC coupled with the Tesla? -Does the Tesla inverter

Re: [RE-wrenches] SMA Tripower

Woah way to pull out an awesome NEC reference Garrison! I'm not totally convinced it applies though, since Article 220 is specifically for branch circuits, feeders and service load calcs. The circuit in question here is defined by 690.1(b) as an *inverter output circuit*, the OCPD has to be sized

Re: [RE-wrenches] SW series fuse rating

Reverse current and max series fuse are not always the same, check out this Solar Frontier manual, pg 3: http://www.solar-frontier.com/eng/cs/groups/co_en_product/documents/document/mdaw/mdey/~edisp/c012760.pdf Rebekah Hren On Mon, Mar 21, 2016 at 3:58 PM, Kristopher Schmid <

Re: [RE-wrenches] Shading from Overhead Transmission Lines

I'd be more worried about induced current/voltage on metal/conductors in the PV array, which seems like it could cause issues with GFP devices, and possibly unsafe conditions. I worked on one large array (5 MW) where the point of interconnection was parallel to / under high voltage lines. Even

Re: [RE-wrenches] Fwd: Solar Edge Optimizer failures

Hi Lena, That's really interesting, thanks for sharing. What I'm curious about is why the arc-fault detection in the SolarEdge inverter didn't detect any problem before the optimizers failed...as this sounds like an arc-faulting situation. I wonder if it has to do with where exactly the fault

[RE-wrenches] Secure/support PV wire requirements?

Hi, Wondering if anyone has insight into Code requirements for securing/supporting PV wire behind the modules? I am aware that USE-2 sends you to Section 334.30 requirements for Type NM (12" from box, every 4.5 '). However, I think this is totally bogus, for 2 reasons. 1) Section 338.10(B)(4)(b)

Re: [RE-wrenches] Outback customer service?

Advice I often give to students in PV classes: if you are trying to decide between two similar pieces of equipment at a similar cost (rack, inverter, modules, whatever), try calling the tech support line to ask a technical question and see what happens. Does anyone answer and how quickly? If so

Re: [RE-wrenches] traveling with digital meters

I agree, check probes, carry meters, TSA is too inconsistent to figure out if it's always going to be let through. However, I just barely squeaked through entrance customs last week, there was a $2000 limit for bringing equipment into country. Check and make sure that you won't have to pay customs

Re: [RE-wrenches] Adding battery backup to Enphase

>From my discussions with Enphase at Intersolar/SPI I do not believe their first gen battery will be capable of or designed for battery backup, it was designed for "energy management" as mentioned. Sounded like it would be another year at least before they staart selling it for battery backup

Re: [RE-wrenches] Battery bank calculator

Trojan manufacturer specific: http://www.batterysizingcalculator.com/ ​ ___ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings:

[RE-wrenches] off-grid propane tankless water heater advice

, but it is a phantom load for off-grid and I'm not sure it's a great idea to manually switch the tank power supply on/off several times day? Thanks! Rebekah Hren -- Tel: 336.266.8800 NABCEP Certified Solar PV Installation Professional™ 091209-85 NC Licensed Electrical Contractor

Re: [RE-wrenches] Solaredge Storedge

to the New Yorker refuting this inanity and telling Bill M to do his homework. Send me an email off-list if anyone wants to follow-up. Rebekah Hren On Mon, Jun 29, 2015 at 1:36 PM, Kirk Herander k...@vtsolar.com wrote: Here’s the reply I just got back from Solaredge: “As this stands ATM Tesla

Re: [RE-wrenches] Solaredge Storedge

I don't have any info, but the StorEdge diagram is confusing to me when it says energy independence. I can see a simple compatibility between the Powerwall DC voltage (300 to 400VDC) and the SolarEdge operating voltage, ~350VDC, and I can also see how this setup could be used to maximize

Re: [RE-wrenches] ConnectDER

Relevant article in HP includes good commentary: http://www.homepower.com/articles/solar-electricity/design-installation/methods-streamlined-supply-side-interconnection On Tue, May 26, 2015 at 11:10 AM, Dave Click davecl...@fsec.ucf.edu wrote: I have had two of these on my house (I upgraded

Re: [RE-wrenches] ITC

Yes, I agree with Kris. The tax credit is applied as a deduction to line 44 tax (on taxable income) but the self-employment tax is then added on line 56. But the same is true of all other deductions, exemptions, and credits too. And it doesn't change the fact that if someone has no taxable

Re: [RE-wrenches] Aquian Energy Batteries.

Just a reminder that there was a long list thread about these batteries in the fall: https://www.mail-archive.com/search?l=re-wrenches%40lists.re-wrenches.orgq=aquionsubmit.x=20submit.y=17 In particular Phil Undercuffler had some very interesting comments:

Re: [RE-wrenches] Code reference request

in accordance with NEC article 250.166. What am I missing? Thanks, Dana Dana Brandt Ecotech Energy Systems, LLC www.ecotechenergy.com d...@ecotechenergy.com 360.318.7646 On Tue, Oct 28, 2014 at 11:30 AM, Rebekah Hren rebekah.h...@o2energies.com wrote: If you are on 2014: 690.47(B

Re: [RE-wrenches] Code reference request

If you are on 2014: 690.47(B) An ac equipment grounding system shall be permitted to be used for equipment grounding of inverters and other equipment *and for the ground-fault detection reference for * *ungrounded PV systems.* and 690.47(C)(3) *For ungrounded systems, this con**ductor shall

Re: [RE-wrenches] Thirsty batteries: Daily absorb cycles on top of grid powered float

I'm just wondering if anyone could tell me if I have programmed this right on my own off-grid cabin system with an Outback FX80 - If I set the re-bulk fairly low (like 24.5 volts for a 24 volt system) I should avoid bulk/absorb charging on days when the batteries are not being cycled? There are

Re: [RE-wrenches] Inverters Maximum Input Ratings

) into account in the simulations, which could lead to overestimated generation. I realize hot inverter temperatures may not coincide with the colder temps that usually create clipping, but the higher the ratio goes the more often we see an overlap in hot days/high temps/clipping. Cheers, Rebekah Hren

Re: [RE-wrenches] Ct Utility test requirement?

this wouldn't be the way to do this test. Cheers, Rebekah Hren On Mon, Aug 4, 2014 at 11:24 AM, Allen Frishman amfr...@aeonsolar.com wrote: Wrenchers, The Ct Utility company CLP requires the following as part of the verification test. Because this is a three-phase service, the witness test

Re: [RE-wrenches] (no subject)

protection can be positioned under a module. However I don't think it's a great idea and wouldn't want to maintain a system with fuses on a roof under the array, but this seems like a grey area in the Code and getting the AHJ interpretation would be advisable. Rebekah Hren On Mon, Apr 28, 2014

[RE-wrenches] Security / theft questions

? Using guards? If a theft occurred, was it during or after installation? 3) What about theft from non-secured sites?  4) Is theft something you are worried about on residential/ commercial roof systems after the installation is complete?  Many thanks! Rebekah Hren O2 Energies,  North

[RE-wrenches] Sizing 3 phase OCPD - main

Hi wrenches,  I have a question about sizing the main OCP breaker for a panel combining the output of several true three-phase output inverters. To be precise - 10 of the  Refusol 20kW, which connect to  480V/277 Y with a max output of 24.1 amps, each inverter has a 3 pole breaker, line a, b, c

Re: [RE-wrenches] NEC Plus

had to call the NFPA to get a new download added three times. I think the encryption got a little out of hand. Rebekah Hren Tel (336) 266-8800 From: Drake drake.chamber...@redwoodalliance.org To: RE-wrenches re-wrenches@lists.re-wrenches.org Sent: Tue

Re: [RE-wrenches] GEC for Enphase inverters

. A conductor used to connect the system grounded conductor...to a point on the grounding electrode system. So this means that for Enphase systems the AC EGC (which is also the DC GEC) should be at minimum 8 awg (250.66) and continuous? Seems like it to me.  Rebekah Hren --- On Tue, 9/14/10, Mark Frye

Re: [RE-wrenches] AC breakers used in DC applications

Hi,One thing to be clear about is whether these are listed for 48 volt systems, or for max 48 volts?I was under the impression that they were max 48 volts, meaning you really shouldn't use them on a system 24volts nominal. Rebekah HrenNorth Carolina  http://thecarbonfreehome.com/ --- On Sat,

Re: [RE-wrenches] Amphenol Helios as MC4 substitute

Hi Jay! I bet it does! What a freakin racket mc had going! Looking forward to battery lab this summer! Rebekah Hren (336)266-8800 On Apr 11, 2010, at 10:37 AM, jay peltz j...@asis.com wrote: HI Rebekah, The most amazing thing is that the tool is only $100 even on this site. Since the parts

Re: [RE-wrenches] 3 Phase Grid Tie with Battery Backup

are sized correctly (solar pro had a recent article on unbalanced 3 phase wire sizing). This of course limits your backed up loads to 120V (w/out a transformer). Rebekah Hren North Carolina From: Allan Sindelar al...@positiveenergysolar.com To: RE-wrenches