new member here - looking to learn

[ajonestx]

Sorry for the delay Oregon_phil - took some time to get an installer to pull one of the panels down for me - yes, 327W panels (model number: SPR-E20-327-C-AC) with 320W micro inverter (model number: MI-C-320-US208/240-10 made by SunPower). I think I got one of the last SunPower micro-inverter installs before they started outsourcing to Enphase.

does anyone have guidance on how to make a SunPower warranty claim?

[ajonestx]

327 watt panels with 320 watt microinverters seems an odd enough combination to be googleable. Is this the combination that you have? If yes, is there some history on SunPower Microinverters (other than Sunpower now uses Enphase)? If this is not relevant, sorry for the diversion.

Sorry for the delay Oregon_phil - took some time to get an installer to pull one of the panels down for me - yes, 327W panels (model number: SPR-E20-327-C-AC) with 320W micro inverter (model number: MI-C-320-US208/240-10 made by SunPower). I think I got one of the last SunPower micro-inverter installs before they started outsourcing to Enphase.

[ajonestx]

This is not much to go on
What brand and hopefully actual Model Numbers (should be in all your warranty / manuals given at end of installation)

Hello Scrambler! Delayed response to your question... Sorry. As I was not given any manuals at the time of the micro inverter replacement, I went back to the installer - they did not have any record of what was installed and could not help me. So, I hired another installer and they pulled one of the panels down for me to take pictures. The replacement micro inverter model number is, MI-C-320-US208/240-10 made by SunPower.

They also tested the panel while they were on the ground. On the day of test, in full sun and clear skies (no clouds or shade), the individual panel was producing wattage above nameplate (at 359 watts), but the individual micro inverters were only allowing about 260 to 270 watts to pass through.

[ajonestx]

This is not much to go on
What brand and hopefully actual Model Numbers (should be in all your warranty / manuals given at end of installation)

No manuals received at end of installation. Let me do a little homework this week and give you more data (actual model numbers). Having difficulty getting data...

[Mike90250]

I heard of a failure mode being traced to the "installer" gathering up all the gear, hanging by the cables (so as to carry more per trip) and after being swung around the water seals on the cables failed, couple years later, the gear ( I can't recall if they were micro's or optimizers ) had a +80% failure rate

[scrambler]

it states that the micro inverts are 320's..

This is not much to go on
What brand and hopefully actual Model Numbers (should be in all your warranty / manuals given at end of installation)

[oregon_phil]

327 watt panels with 320 watt microinverters seems an odd enough combination to be googleable. Is this the combination that you have? If yes, is there some history on SunPower Microinverters (other than Sunpower now uses Enphase)? If this is not relevant, sorry for the diversion.

[ajonestx]

That is a better graph, having the real vertical scale from zero gives a better perspective, the drop in the first half being less pronounced.
Can you share what micro inverters were initially installed, and did you find which ones are installed now.

Did they, or can they tell you what lead to ALL of them failing, because it is very unlikely you were unlucky enough to get a bad batch, and it would seem like may there was a flaw in the installation itself leading to their death. If so it would be nice to know what and what was done to remedy the issue so they would not fail again.

My graph is getting better as I add more data and tweak the presentation - I might add notes and a better index next time! I am an average excel user and creating graphs and plots are not my expertise. Practice makes perfect.

In my agreement as well as the engineering documents, it states that the micro inverts are 320's. I have made lots of phone calls this morning and sent lots of emails, but have yet to confirm what model of micro inverters are installed now. Still digging, but still do not have the new micro inverter information yet - I will get it somehow.

I was never told what lead the original micro inverters to fail. Actually, I don't think they ever admitted that they did fail... only that after 6 months of emails and phone calls did a truck show up one day to replace them. I should have been more in their business and documented what the replacement equipment was. I did hear that there were other customers who had their micro inverters replaced at about the same time, so I am inclined to think that there was a problem with the micro inverter and not the installation.

[scrambler]

That is a better graph, having the real vertical scale from zero gives a better perspective, the drop in the first half being less pronounced.
Can you share what micro inverters were initially installed, and did you find which ones are installed now.

Did they, or can they tell you what lead to ALL of them failing, because it is very unlikely you were unlucky enough to get a bad batch, and it would seem like may there was a flaw in the installation itself leading to their death. If so it would be nice to know what and what was done to remedy the issue so they would not fail again.

[ajonestx]

Well this is a very important data point, you need to get the make and exact model of the original micro inverters as well as the one for the new ones.

All that said, there is still the discrepancy between first and second half of year....

Scrambler - I have a working theory on the discrepancy between the first half of the year and the second half of the year. I looked back into old emails and there were some odd micro-inverter errors reporting in June of 2017. My theory is that maybe they started failing in June of 2017 with their ultimate replacement one year later in May of 2018. I added max kW to the chart for 2018 below in cyan with a 25 day average trend line.

[ajonestx]

Well this is a very important data point, you need to get the make and exact model of the original micro inverters as well as the one for the new ones.
(you should not have to go on the rood for that, your installer should provide that information!)
You also need to tells us if All of them were replaced or just some of them
You also need to tell when they were replaced (all at once on a specific date, or across what period of time)
Finally you need to say why they were replaced, did they all fail to zero? that would be strange for micro inverter to all fail at the same time.

All that said, there is still the discrepancy between first and second half of year....

ok. I have the model number of the originally installed micro inverters from my agreement with the original installer. The replacements were installed by a 3rd party installer - I'll look into what I can find on the replacement model numbers were.

ALL of the micro inverters were replaced at the same time and turned back on June 4, 2018. I am pretty sure they ALL failed to zero over a period of time - since I do not have access to inverter data, I can only look at system drops and they appear to begin dropping down about six months prior to 100% failure. On the last day before the system was turned off (May 23, 2018), the 5,760 W system maxed out at 660 W.

Let me take another look at the data and think about the discrepancy between the first and second half of the year.

I really appreciate all the help here people!

[scrambler]

Well this is a very important data point, you need to get the make and exact model of the original micro inverters as well as the one for the new ones.
(you should not have to go on the rood for that, your installer should provide that information!)
You also need to tells us if All of them were replaced or just some of them
You also need to tell when they were replaced (all at once on a specific date, or across what period of time)
Finally you need to say why they were replaced, did they all fail to zero? that would be strange for micro inverter to all fail at the same time.

All that said, there is still the discrepancy between first and second half of year....

[ajonestx]

well that’s a decent reason why 2017 is the anomaly in your performance. Seems like 2019,2020 and 2021 are performing within a tight range. Any idea on what the inverter change was?

no clue what the inverters were changed to, only that the original ones failed and they replaced them under warranty.

[RichardCullip]

... Ialso wonder if maybe when the inverters were replaced in 2018, that maybe I got a bad batch and they are not performing up to specs at 320W in subsequent years...

well that’s a decent reason why 2017 is the anomaly in your performance. Seems like 2019,2020 and 2021 are performing within a tight range. Any idea on what the inverter change was?

[ajonestx]

If you have Enphase micro inverters, there are two things I believe you can do.

Also, can you clarify your shade issue. Need to know what the shade comes from. Is it a fixed structure that does not change overtime, or a variable structure like trees?
If so check when does the shade happen (hours of the day), and what predominant month it happens (shade can be bigger in winter season when the sun is low and the shadows get longer). Then extrapolate how that will change if the trees are growing taller (longer hours periods, and longer day periods...)

I missed this one question about trees in my last response. Yes, our shade is variable - trees. We have trimmed them once (December of 2018) since install in 2017. Since then, one has gotten shorter (rot at the top) and one has gotten taller. Trees are deciduous and during the winter, sun passes mostly through them and in the Summer, sun passes over them. Based on "sun eye" shade analysis, originally estimated production levels were discounted by 16% for the shade. it is probably time to trim them again. Every panel sees full sun during the day, so that is why I am thinking that kW is the right focus (I think).