94% could just be year to year variability. I know that PVwatts says it can vary a bit -- if you click on the link right under the total kWh per year number, it gives a chart of expected range and such for that location. There are sites that actually measure variability from year to year and publish maps of how each year compared with "average". I can't remember who that is off the top of my head, but maybe someone else will. With climate change, some regions are regularly trending higher than average and others lower than average in PSH, in addition to other weather metrics.
Also... on the issue of variability. I have been recording daily PSH for my site for the past three years, and have found that it varies even more than I had expected, especially when you get to month by month. I measured from 77% to 88% of expected for the annual PSH, and months from 17% to 114% of expected. Of particular significance is that my winters are MUCH lower than PVwatts claims they should be. The best I've measured december/January was 71% of expected, and most years it was well under 50%. One particularly foggy december was 17%. I don't know how much of this is that my site is 50 miles away from the nearest airport where the longer term data was measured, plus 1800 feet higher elevation, so different fog and cloud patterns. But I think another issue is that I am including shading in my measurements obviously (sensor is right next to my array, with real world shading from 150 foot tall trees 300 feet away), whereas the default PVwatts includes no shading. In most real sites that don't have a horizon to horizon view, the effect of shading is going to be more than PV watts estimates -- maybe only a few percent, but still an effect. Back to the array. Like someone mentioned, a thermal camera is pretty good at picking out the part of the array that is not contributing, so if you have shorted bypass diodes, you should be able to see the slightly hotter parts of the array that are bypassed. Also a measurement of the temperature of the array can let you calculate what the actual Vmp or Voc should be and compare that to measured. And finally, do the Tigo RSD's give an output when turned off? The APsystems ones give about 1 volt each when turned off, so you can measure and make sure you have the right number of modules in a string. Though, it's not always exactly 1 volt, so on longer strings, not always accurate. But it gives you an idea if there's a dead RSD perhaps, that's passing through current from the others, but not turning on its module. That should also show up on the thermal camera, an entire module that's hotter than the rest of the array. Zeke From: Dave Tedeyan <[email protected]> To: RE-wrenches <[email protected]> Subject: Re: [RE-wrenches] Q.PEAK DUO BLK-G6+ underproduction Message-ID: <CAM3Q7f3pCPdyEN+QHgLSBOfKAQUtUUxj1eLs0GO3YZ=v7a0...@mail.gmail.com> Content-Type: text/plain; charset="utf-8" I must admit, this is a little embarrassing... this is what I get for trying to work with a head cold. I didn't remember that there was a change order on this one, and the original contract was for a larger system than what eventually got installed. I was looking at the producion estimate from the original larger system, which was around 17MWh/year. The actual production estimate is closer to 14.3MWh, and the system has averaged 13.5MWh over the past 5 years. So, 94% is not nearly as bad as I originally thought, although it is still not good either. The voltages that I am seeing on the Sunny Portal monitoring are still lower than I would expect. I think it is still worth checking out with an IR scan once the snow goes away and the sun comes back here in upstate NY. The recommendations for doing a curve trace would be the best troubleshooting step, although I have not yet invested in one of those. All this still leads me to believe that these Qcell modules may be not quite be performing to spec, but they are not as ridiculously far off as I feared. Cheers, Dave On Wed, Feb 11, 2026 at 2:03 PM <[email protected]> wrote: > Send RE-wrenches mailing list submissions to > [email protected] > > To subscribe or unsubscribe via the World Wide Web, visit > > http://lists.re-wrenches.org/listinfo.cgi/re-wrenches-re-wrenches.org > or, via email, send a message with subject or body 'help' to > [email protected] > > You can reach the person managing the list at > [email protected] > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of RE-wrenches digest..." > > > When responding to posts within the Digest, be sure to restore the > Subject: line to the exact original, and please edit out any extraneous > lines from the quoted message. > > > > Today's Topics: > > 1. Re: Q.PEAK DUO BLK-G6+ underproduction > (pieter offgridenterprises.org) > 2. Re: Q.PEAK DUO BLK-G6+ underproduction (AE Solar) > 3. Re: Q.PEAK DUO BLK-G6+ underproduction (Jay) > 4. Re: Q.PEAK DUO BLK-G6+ underproduction (Glenn) > 5. Re: Q.PEAK DUO BLK-G6+ underproduction (Roy Rakobitsch) > 6. Big Charger, Small Generator (Mark Frye) > 7. Re: Big Charger, Small Generator (Tyrone Houck) > 8. Re: Big Charger, Small Generator (Mac Lewis) > 9. Re: Big Charger, Small Generator (Jay) > 10. Re: Q.PEAK DUO BLK-G6+ underproduction (Dave Tedeyan) > 11. Fwd: Optics Data sunset (William Miller) > 12. Re: Q.PEAK DUO BLK-G6+ underproduction (Glenn) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Tue, 10 Feb 2026 22:31:02 +0000 > From: pieter offgridenterprises.org <[email protected]> > To: RE-wrenches <[email protected]> > Subject: Re: [RE-wrenches] Q.PEAK DUO BLK-G6+ underproduction > Message-ID: > < > ds0pr11mb80842ff13eb7cd678e5cfc85a0...@ds0pr11mb8084.namprd11.prod.outlook.com > > > > Content-Type: text/plain; charset="us-ascii" > > Although VOC measurements using the ambient air temperature in the area > are interesting. Perhaps a more thorough diagnosis is in order. As a first > step I recommend getting array ISC, VOC, MODULE temperature, and solar > irradiance. There is equipment available to make these tests easy, or if > you are on a budget, it can be done with multiple pieces of less expensive > equipment. Based on the findings, you can take the next step and use a > curve tracer. A visual inspection and perhaps thermal imaging and the use > of UV lights can also be used to look for damaged, dirty or defective > modules. > Pieter Huebner > Project Manager > Off Grid Enterprises > ________________________________ > From: RE-wrenches <[email protected]> on behalf > of Dave Tedeyan via RE-wrenches <[email protected]> > Sent: Tuesday, February 10, 2026 2:06 PM > To: RE-wrenches <[email protected]> > Cc: Dave Tedeyan <[email protected]> > Subject: [RE-wrenches] Q.PEAK DUO BLK-G6+ underproduction > > Hi All, > > I was just reviewing a site installed about 5 years ago and am finding it > is not doing nearly as well as I would have expected. Most of our sites > produce relatively close to our projections, but this one is pretty far > off. There are 3 strings of 12 Q.PEAK DUO BLK-G6+ modules. Two strings go > to a 7.7kw inverter and one string goes to a 3.8kw inverter - both of which > are the -41 series SMA inverters. There are Tigo TS4-R-F rapid shutdown > devices on all the modules. > > Vmp for 12 of these panels should be about 407V at STC. At 50C (which is > really hot for upstate NY), the Vmp should be around 380V. On a perfect > summer day, I am seeing Vmp of around 320V. On a perfect spring day > (cooler, with some power clipping, I am seeing Vmp of around 355V. And on a > perfect winter day (when there was no snow) Vmp is around 365V. All three > strings are pretty consistent with each other, so I don't think that there > are specific installation issues with any panels, unless we managed to > forget to wire in two panels in all three strings which is extremely > unlikely. > > So, I can only think of two things that might be at play here: > 1. Maybe these modules are just crap, and are not at all performing to > spec. > 2. Maybe the Tigo devices are causing issues. > > Has anyone out there experienced production issues like this? Everything > appears normal, it is on an open rooftop, and there are not things like > partial shading, weeds, bird poop, or other soiling affecting the modules. > I don't have another site with the same modules that also has good > monitoring data, but maybe some of you do! > > Thanks for the consideration! > Cheers, > Dave > -- > > [ > https://ci3.googleusercontent.com/mail-sig/AIorK4zoZ4JdaR79CFcLmy74s-VRVaVovMEuRmw5pzk3XBT09h8ZNlFbMgJ4yHW2Uxf91_2codJGB4DALADN > ] > Dave Tedeyan, P.E. > Owner | Sungineer Solar > p: he | him | his > a: 1653 Slaterville Rd. | Ithaca, NY 14850 > w: www.sungineersolar.com<http://www.sungineersolar.com/> > c: (607) 270-0370 > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260210/ef803356/attachment-0001.htm > > > > ------------------------------ > > Message: 2 > Date: Tue, 10 Feb 2026 17:42:59 -0500 > From: AE Solar <[email protected]> > To: RE-wrenches <[email protected]> > Subject: Re: [RE-wrenches] Q.PEAK DUO BLK-G6+ underproduction > Message-ID: > <CAHA29TQb+WaLqK4j3OTLPihr= > [email protected]> > Content-Type: text/plain; charset="utf-8" > > We had an install with the Q.PEAK DUO BLK-G6+ 340 where there was a bad > diode in a panel or two, and production was reduced by approximately 25% > +/- on > each panel. Same with some Q.PEAK DUO BLK-L G5.2 400 watt panels and Q.PEAK > DUO BLK-L G5.3 400 watt panels. All those installs were with Enphase or > SolarEdge so it was pretty easy to diagnose remotely. I believe in all > those cases the failure happened within the first year of being installed. > I think those installs were all around 2020 or 2021 maybe, and we didn't > have any issues with QCells before or after that time period. > > Adam Katzman (he/him) > Autonomous Energies | Owner/Operator > www.AutonomousEnergies.com <http://www.autonomousenergies.com> > (518) 567-1468 > > > > > On Tue, Feb 10, 2026 at 4:16?PM Dave Tedeyan via RE-wrenches < > [email protected]> wrote: > > > Hi All, > > > > I was just reviewing a site installed about 5 years ago and am finding it > > is not doing nearly as well as I would have expected. Most of our sites > > produce relatively close to our projections, but this one is pretty far > > off. There are 3 strings of 12 Q.PEAK DUO BLK-G6+ modules. Two strings go > > to a 7.7kw inverter and one string goes to a 3.8kw inverter - both of > which > > are the -41 series SMA inverters. There are Tigo TS4-R-F rapid shutdown > > devices on all the modules. > > > > Vmp for 12 of these panels should be about 407V at STC. At 50C (which is > > really hot for upstate NY), the Vmp should be around 380V. On a perfect > > summer day, I am seeing Vmp of around 320V. On a perfect spring day > > (cooler, with some power clipping, I am seeing Vmp of around 355V. And > on a > > perfect winter day (when there was no snow) Vmp is around 365V. All > three > > strings are pretty consistent with each other, so I don't think that > there > > are specific installation issues with any panels, unless we managed to > > forget to wire in two panels in all three strings which is extremely > > unlikely. > > > > So, I can only think of two things that might be at play here: > > 1. Maybe these modules are just crap, and are not at all performing to > > spec. > > 2. Maybe the Tigo devices are causing issues. > > > > Has anyone out there experienced production issues like this? Everything > > appears normal, it is on an open rooftop, and there are not things like > > partial shading, weeds, bird poop, or other soiling affecting the > modules. > > I don't have another site with the same modules that also has good > > monitoring data, but maybe some of you do! > > > > Thanks for the consideration! > > Cheers, > > Dave > > -- > > > > Dave Tedeyan, P.E. > > Owner | Sungineer Solar > > p: he | him | his > > a: 1653 Slaterville Rd. | Ithaca, NY 14850 > > w: www.sungineersolar.com <http://www.sungineersolar.com/> > > c: (607) 270-0370 > > _______________________________________________ > > 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 > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260210/2f7e29ee/attachment-0001.htm > > > > ------------------------------ > > Message: 3 > Date: Tue, 10 Feb 2026 14:39:19 -0700 > From: Jay <[email protected]> > To: RE-wrenches <[email protected]> > Subject: Re: [RE-wrenches] Q.PEAK DUO BLK-G6+ underproduction > Message-ID: <[email protected]> > Content-Type: text/plain; charset="us-ascii" > > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260210/131b37e8/attachment-0001.htm > > > > ------------------------------ > > Message: 4 > Date: Tue, 10 Feb 2026 16:52:48 -0500 > From: Glenn <[email protected]> > To: RE-wrenches <[email protected]> > Subject: Re: [RE-wrenches] Q.PEAK DUO BLK-G6+ underproduction > Message-ID: <[email protected]> > Content-Type: text/plain; charset="us-ascii" > > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260210/e607152e/attachment-0001.htm > > > > ------------------------------ > > Message: 5 > Date: Tue, 10 Feb 2026 18:37:52 -0600 > From: Roy Rakobitsch <[email protected]> > To: RE-wrenches <[email protected]> > Subject: Re: [RE-wrenches] Q.PEAK DUO BLK-G6+ underproduction > Message-ID: > <CAL2u1ufcpxZ_Wi-GBSHi_reSHqZ9fEH= > [email protected]> > Content-Type: text/plain; charset="utf-8" > > It would be fairly easy to spot bypass diode issues or cell current > imbalance issues with a hand-held IR imager on a decently sunny day. Maybe > time to go on the roof and take a peek? > > > Roy Rakobitsch > > Windsine LLC > 631-514-4166 > > On Tue, Feb 10, 2026, 18:25 Jay via RE-wrenches < > [email protected]> wrote: > > > Looking at it from performance ie watts, how far off does it appear to > be? > > > > Jay > > > > > > > > On Feb 10, 2026, at 2:07?PM, Dave Tedeyan via RE-wrenches < > > [email protected]> wrote: > > > > ? > > Hi All, > > > > I was just reviewing a site installed about 5 years ago and am finding it > > is not doing nearly as well as I would have expected. Most of our sites > > produce relatively close to our projections, but this one is pretty far > > off. There are 3 strings of 12 Q.PEAK DUO BLK-G6+ modules. Two strings go > > to a 7.7kw inverter and one string goes to a 3.8kw inverter - both of > which > > are the -41 series SMA inverters. There are Tigo TS4-R-F rapid shutdown > > devices on all the modules. > > > > Vmp for 12 of these panels should be about 407V at STC. At 50C (which is > > really hot for upstate NY), the Vmp should be around 380V. On a perfect > > summer day, I am seeing Vmp of around 320V. On a perfect spring day > > (cooler, with some power clipping, I am seeing Vmp of around 355V. And > on a > > perfect winter day (when there was no snow) Vmp is around 365V. All > three > > strings are pretty consistent with each other, so I don't think that > there > > are specific installation issues with any panels, unless we managed to > > forget to wire in two panels in all three strings which is extremely > > unlikely. > > > > So, I can only think of two things that might be at play here: > > 1. Maybe these modules are just crap, and are not at all performing to > > spec. > > 2. Maybe the Tigo devices are causing issues. > > > > Has anyone out there experienced production issues like this? Everything > > appears normal, it is on an open rooftop, and there are not things like > > partial shading, weeds, bird poop, or other soiling affecting the > modules. > > I don't have another site with the same modules that also has good > > monitoring data, but maybe some of you do! > > > > Thanks for the consideration! > > Cheers, > > Dave > > -- > > > > Dave Tedeyan, P.E. > > Owner | Sungineer Solar > > p: he | him | his > > a: 1653 Slaterville Rd. | Ithaca, NY 14850 > > w: www.sungineersolar.com <http://www.sungineersolar.com/> > > c: (607) 270-0370 > > _______________________________________________ > > 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 > > > > _______________________________________________ > > 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 > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260210/a4a8d68f/attachment-0001.htm > > > > ------------------------------ > > Message: 6 > Date: Wed, 11 Feb 2026 12:37:39 +0000 > From: Mark Frye <[email protected]> > To: RE-wrenches <[email protected]> > Subject: [RE-wrenches] Big Charger, Small Generator > Message-ID: > < > ds7pr19mb59524fb8e9d6fe488cdd0b5eb1...@ds7pr19mb5952.namprd19.prod.outlook.com > > > > Content-Type: text/plain; charset="us-ascii" > > Folks, > > If I have a larger AC powered battery charge, say 3kW and I have a battery > bank that may want to pull some current, want will happen if I try to run > the charger with a small, say 1.2 kW generator? > > Thanks, > > Mark > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260211/9c7065e1/attachment-0001.htm > > > > ------------------------------ > > Message: 7 > Date: Wed, 11 Feb 2026 05:24:45 -0800 > From: Tyrone Houck <[email protected]> > To: RE-wrenches <[email protected]> > Subject: Re: [RE-wrenches] Big Charger, Small Generator > Message-ID: > < > caeqh54m-zcwbxv5ufkpcwk08w6xcgh4f0usmzplebyve0dp...@mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > The generator will bog down under load and shut off unless there is a way > to program to charge at a lower rate. > > > > > > > > > > > On Wed, Feb 11, 2026, 5:01?AM Mark Frye via RE-wrenches < > [email protected]> wrote: > > > Folks, > > > > > > > > If I have a larger AC powered battery charge, say 3kW and I have a > battery > > bank that may want to pull some current, want will happen if I try to run > > the charger with a small, say 1.2 kW generator? > > > > > > > > Thanks, > > > > > > > > Mark > > _______________________________________________ > > 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 > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260211/fbfdf0ab/attachment-0001.htm > > > > ------------------------------ > > Message: 8 > Date: Wed, 11 Feb 2026 06:34:35 -0700 > From: Mac Lewis <[email protected]> > To: RE-wrenches <[email protected]> > Subject: Re: [RE-wrenches] Big Charger, Small Generator > Message-ID: > <CAOABG4_G-XM2uvMy_Dd30v_cS= > [email protected]> > Content-Type: text/plain; charset="utf-8" > > Hi Mark, > > It will stall the generator and/or it will shutdown on overload and or trip > a breaker. > > However, many battery chargers have some adjustability so you may be able > to adjust it down to the sweet spot. The way I like to do it is start with > the charger very low, then slowly adjust the load up. At some point, the > generator will sound like its working hard but not overloaded. Just know > that you may need to adjust this for various operating conditions > (temperature is the big one) or if you are moving it around, elevation. > > Be prepared to be disappointed by the generators performance, battery > chargers can be difficult loads for low quality generators. > > > > > Mac Lewis > > *"Yo solo s? que no s? nada." -S?crates* > > On Wed, Feb 11, 2026, 6:01?AM Mark Frye via RE-wrenches < > [email protected]> wrote: > > > Folks, > > > > > > > > If I have a larger AC powered battery charge, say 3kW and I have a > battery > > bank that may want to pull some current, want will happen if I try to run > > the charger with a small, say 1.2 kW generator? > > > > > > > > Thanks, > > > > > > > > Mark > > _______________________________________________ > > 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 > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260211/ec71c700/attachment-0001.htm > > > > ------------------------------ > > Message: 9 > Date: Wed, 11 Feb 2026 07:15:11 -0700 > From: Jay <[email protected]> > To: RE-wrenches <[email protected]> > Cc: Mac Lewis <[email protected]>, RE-wrenches > <[email protected]> > Subject: Re: [RE-wrenches] Big Charger, Small Generator > Message-ID: <[email protected]> > Content-Type: text/plain; charset="us-ascii" > > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260211/1c623023/attachment-0001.htm > > > > ------------------------------ > > Message: 10 > Date: Wed, 11 Feb 2026 09:26:13 -0500 > From: Dave Tedeyan <[email protected]> > To: RE-wrenches <[email protected]> > Subject: Re: [RE-wrenches] Q.PEAK DUO BLK-G6+ underproduction > Message-ID: > <CAM3Q7f3pCPdyEN+QHgLSBOfKAQUtUUxj1eLs0GO3YZ= > [email protected]> > Content-Type: text/plain; charset="utf-8" > > I must admit, this is a little embarrassing... this is what I get for > trying to work with a head cold. I didn't remember that there was a change > order on this one, and the original contract was for a larger system than > what eventually got installed. I was looking at the producion estimate from > the original larger system, which was around 17MWh/year. The actual > production estimate is closer to 14.3MWh, and the system has averaged > 13.5MWh over the past 5 years. So, 94% is not nearly as bad as I originally > thought, although it is still not good either. > > The voltages that I am seeing on the Sunny Portal monitoring are still > lower than I would expect. I think it is still worth checking out with an > IR scan once the snow goes away and the sun comes back here in upstate NY. > The recommendations for doing a curve trace would be the best > troubleshooting step, although I have not yet invested in one of those. All > this still leads me to believe that these Qcell modules may be not quite be > performing to spec, but they are not as ridiculously far off as I feared. > > Cheers, > Dave > > On Tue, Feb 10, 2026 at 8:50?PM Roy Rakobitsch via RE-wrenches < > [email protected]> wrote: > > > It would be fairly easy to spot bypass diode issues or cell current > > imbalance issues with a hand-held IR imager on a decently sunny day. > Maybe > > time to go on the roof and take a peek? > > > > > > Roy Rakobitsch > > > > Windsine LLC > > 631-514-4166 > > > > On Tue, Feb 10, 2026, 18:25 Jay via RE-wrenches < > > [email protected]> wrote: > > > >> Looking at it from performance ie watts, how far off does it appear to > be? > >> > >> Jay > >> > >> > >> > >> On Feb 10, 2026, at 2:07?PM, Dave Tedeyan via RE-wrenches < > >> [email protected]> wrote: > >> > >> ? > >> Hi All, > >> > >> I was just reviewing a site installed about 5 years ago and am finding > it > >> is not doing nearly as well as I would have expected. Most of our sites > >> produce relatively close to our projections, but this one is pretty far > >> off. There are 3 strings of 12 Q.PEAK DUO BLK-G6+ modules. Two strings > go > >> to a 7.7kw inverter and one string goes to a 3.8kw inverter - both of > which > >> are the -41 series SMA inverters. There are Tigo TS4-R-F rapid shutdown > >> devices on all the modules. > >> > >> Vmp for 12 of these panels should be about 407V at STC. At 50C (which is > >> really hot for upstate NY), the Vmp should be around 380V. On a perfect > >> summer day, I am seeing Vmp of around 320V. On a perfect spring day > >> (cooler, with some power clipping, I am seeing Vmp of around 355V. And > on a > >> perfect winter day (when there was no snow) Vmp is around 365V. All > three > >> strings are pretty consistent with each other, so I don't think that > there > >> are specific installation issues with any panels, unless we managed to > >> forget to wire in two panels in all three strings which is extremely > >> unlikely. > >> > >> So, I can only think of two things that might be at play here: > >> 1. Maybe these modules are just crap, and are not at all performing to > >> spec. > >> 2. Maybe the Tigo devices are causing issues. > >> > >> Has anyone out there experienced production issues like this? Everything > >> appears normal, it is on an open rooftop, and there are not things like > >> partial shading, weeds, bird poop, or other soiling affecting the > modules. > >> I don't have another site with the same modules that also has good > >> monitoring data, but maybe some of you do! > >> > >> Thanks for the consideration! > >> Cheers, > >> Dave > >> -- > >> > >> Dave Tedeyan, P.E. > >> Owner | Sungineer Solar > >> p: he | him | his > >> a: 1653 Slaterville Rd. | Ithaca, NY 14850 > >> w: www.sungineersolar.com <http://www.sungineersolar.com/> > >> c: (607) 270-0370 > >> _______________________________________________ > >> 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 > >> > >> _______________________________________________ > >> 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 > >> > >> _______________________________________________ > > 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 > > > > > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260211/ea272326/attachment-0001.htm > > > > ------------------------------ > > Message: 11 > Date: Wed, 11 Feb 2026 06:26:45 -0800 > From: William Miller <[email protected]> > To: RE-wrenches <[email protected]> > Subject: [RE-wrenches] Fwd: Optics Data sunset > Message-ID: > < > caagpqum+n_mwrmc4zd5rof6p3zd1omk3sk7lf7qg7who70o...@mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > FYI > > > William Miller > Miller Solar.com > 805-438-5600 > www.millersolar.com > > > ---------- Forwarded message --------- > From: Outback Power Support <[email protected]> > Date: Wed, Feb 11, 2026 at 5:17?AM > Subject: Re: Optics Data sunset > To: [email protected] <[email protected]> > > > Hi William, > > I can understand your point. This is not something in support hands and > decision is taken in the upper level. Just to let you know that we are > pushing back a month longer for data retrieval. Due to limitations with the > database architecture, the request may timeout, so if you don't receive it > within about an hour, try again, because the request likely timed out. > Timeouts are based on request volume, so it may take several attempts. We > have identified the issue and are working to resolve it as soon as > possible. Meanwhile, try requesting data in shorter time frames. > > Regards, > Omar > *Technical Support* > *O:* 360-618-4363 > Tech Support LIVE Chat Link <https://1621.3cx.cloud/obptechchat> > < > https://www.google.com/maps/search/400+Maple+St+%0D%0A+%0D%0ACommerce,+TX+75428?entry=gmail&source=g > > > avail: 6am-4pm PST > *Outback Power, LLC* > 400 Maple St > < > https://www.google.com/maps/search/400+Maple+St+%0D%0A+%0D%0ACommerce,+TX+75428?entry=gmail&source=g > > > Commerce, TX 75428 > < > https://www.google.com/maps/search/400+Maple+St+%0D%0A+%0D%0ACommerce,+TX+75428?entry=gmail&source=g > > > > ------------------------------ > *From:* William Miller <[email protected]> > *Sent:* 27 January 2026 02:30 > *To:* RE-wrenches <[email protected]> > *Cc:* Outback Power Support <[email protected]> > *Subject:* Optics Data sunset > > You don't often get email from [email protected]. *Learn why this is > important <https://aka.ms/LearnAboutSenderIdentification>* > > Friends: > > > > I sat down today to download historic data from all of my OpticsRE > connected clients. This is pursuant to the notification from Outback that, > as of 2/1/26, the data beyond 6 months will be purged. I have 17 systems > connected and many of them for more than 5 years old. I rely on that data > for occasional troubleshooting and analysis. > > > > In the process I noticed a few odd things: > > > > 1. All of the data over 3 years old has already been purged. The > earliest record is 1/26/2023. > > 2. You can only request a report for a duration of 1 year, so with this > many legacy systems I needed to request a lot of reports, (42, given the > already purged data). This is time consuming and frustrating. Storage is > not expensive and these files are not that large so the policy change seems > to me to be overly parsimonious on the part of Outback. > > 3. I have found the graphic interface on Optics to be very handy. I can > look at a month view and see the daily production and consumption values. > Granted I have to type them into a spreadsheet. With the 15 minute > increments if I want to analyze the average daily solar production for last > January, for example, I am going to have to do some fancy spreadsheet > maneuvers to aggregate these 15 minute intervals. > > 4. The reports arrive via e-mail. So far I have requested 11 reports but > after I received just 4 of them they stopped arriving in my email. It has > been over an hour since I received the last report. > > 5. I am noticing a lot of gaps on the graphs. > > 6. I am noticing the colors on the voltage line graphs is not consistent > from site to site. Many of them are no longer yellow, green and red but > all yellow (orange-ish yellow). It seems to correlate with the setting you > have in Devices for battery type. > > The deadline to archive this data is fast approaching and I worry I just > won?t be able to access it. > > > > Have any of you been through this process yet, and if so, what are your > experiences? > > > > Thanks in advance, > > > > William > > > > William Miller > > Miller Solar > > *www.millersolar.com <http://www.millersolar.com/>* > > CA License C-10 77398 > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260211/6e1aeba1/attachment-0001.htm > > > > ------------------------------ > > Message: 12 > Date: Wed, 11 Feb 2026 12:09:49 -0500 > From: Glenn <[email protected]> > To: RE-wrenches <[email protected]> > Subject: Re: [RE-wrenches] Q.PEAK DUO BLK-G6+ underproduction > Message-ID: <[email protected]> > Content-Type: text/plain; charset="us-ascii" > > An HTML attachment was scrubbed... > URL: < > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20260211/1e29b01c/attachment-0001.htm > > > > ------------------------------ > > Subject: Digest Footer > > _______________________________________________ > 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 > > > > ------------------------------ > > End of RE-wrenches Digest, Vol 19, Issue 48 > ******************************************* > -- Zeke Yewdall PV Engineer NABCEP #031508-89 [email protected] 303-523-3592
_______________________________________________ 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
