New Solaredge system

[Woodenshoes]

Hello there,

Recently I had this new Solaredge system installed.

SE7K with 27 350 WP panels.

Now there are people who say to me the design is faulty.

This causes a number of the optimizers to "hang" at 60 V during the day causing them unable to contribute to the energy production.

Is this indeed the case? What do you think of this?

Overview of the situation:

SZg9tGMmPovUtIGdmghZzlyZ~2.png

This was in February:

Screenshot_20230403-065451.png

Screenshot_20230403-065525.png

[Mike 134]

If you look at the monthly layout tab how close are the panels output to each other? Below is mine for 2 days of April april output.PNG

[J.P.M.]

You paid for a warranty and service as part of the contract you signed.

What did the installer have to say when you contacted him ?

[oregon_phil]

Hello there,

Recently I had this new Solaredge system installed.

SE7K with 27 350 WP panels.

Now there are people who say to me the design is faulty.

This causes a number of the optimizers to "hang" at 60 V during the day causing them unable to contribute to the energy production.

Is this indeed the case? What do you think of this?

27 panels imply two strings. You have multiple roof angles. Draw the string layout of each string in your roof picture. In theory, side by side panels on the same roof pitch should give the same output if there are no other overriding issues. Determine physical panel output by panel for exactly the same timeframe as Mike 123.

You can also search for "Erfahrungsbericht zum Thema "Voltage Blocking" bei SE Anlage" to get a better understanding of the issue.

Disclaimer: I do not own a SE system.

[Woodenshoes]

If you look at the monthly layout tab how close are the panels output to each other? Below is mine for 2 days of April

I don't think our situations are comparable (I have multiple orientations and a lot of shadow from a big tree and the neighbours house), but here you go:

2023-04-03 19_27_13-Layout.png

3 days of April.

You paid for a warranty and service as part of the contract you signed.

What did the installer have to say when you contacted him ?

I contacted him yes, but he says the system works fine (no errors - I already knew that) and I shouldn't worry so much. Also, he told me he ran in through SE Designer which didn't show a lot of optimizer clipping/voltage blocking (<1%), which is true - I've seen the report.

Still, I see a lot of optimizer clipping on sunny days especially in the winter months.

Also today. An example. The panels through 21-27 are the only ones getting full exposure to sunlight in the evening (North East). They get capped at 60 volts and produce far less than capable. See here:

2023-04-03 20_36_35-Grafieken.png

[Mike 134]

I don't think our situations are comparable (I have multiple orientations and a lot of shadow from a big tree and the neighbours house), but here you go:

2023-04-03 19_27_13-Layout.png

3 days of April.



I contacted him yes, but he says the system works fine (no errors - I already knew that) and I shouldn't worry so much. Also, he told me he ran in through SE Designer which didn't show a lot of optimizer clipping/voltage blocking (<1%), which is through. That's his statement.

Your adjacent panels on the same orientations have similar outputs so it would seem the installer is correct. You're looking for one (or more) with the same orientation substantially lagging behind the others. What do the lifetime outputs look like?

[Woodenshoes]

Your adjacent panels on the same orientations have similar outputs so it would seem the installer is correct. You're looking for one (or more) with the same orientation substantially lagging behind the others. What do the lifetime outputs look like?

2023-04-03 20_43_29-Layout.png

Lifetime

[J.P.M.]

2023-04-03 20_43_29-Layout.png

Lifetime

Perhaps you could have the installer explain why he believes the system is operating normally.

[oregon_phil]

For clarity, I was assuming you were in Europe, but now I don't know.

I believe you are using a 3 phase SolarEdge 7K inverter. This inverter input runs nominally at 750Vdc and has a minimum string length of 16; maximum 50 since you have 60volt optimizers. So I retract my earlier statement and now presume all panels are in one long string unless you tell me otherwise.

You have a situation that is similar to "Voltage Blocking bei 20kWp SolarEdge Anlage - Strings neu aufbauen". Please google this example. One string with multiple panels on different roof pitches with a 3 phase inverter that requires 13 panels in full sun otherwise voltage blocking occurs.

[Woodenshoes]

For clarity, I was assuming you were in Europe, but now I don't know.

I believe you are using a 3 phase SolarEdge 7K inverter. This inverter input runs nominally at 750Vdc and has a minimum string length of 16; maximum 50 since you have 60volt optimizers. So I retract my earlier statement and now presume all panels are in one long string unless you tell me otherwise.

You have a situation that is similar to "Voltage Blocking bei 20kWp SolarEdge Anlage - Strings neu aufbauen". Please google this example. One string with multiple panels on different roof pitches with a 3 phase inverter that requires 13 panels in full sun otherwise voltage blocking occurs.

Correct. Europe. And correct SE7K. One long string correct. This is also what Designer said by the way.
I don't think I always have 13 panels in full sun...

Do you think the installer made a mistake? And is it fixable?

Perhaps you could have the installer explain why he believes the system is operating normally.

You don't think it is? Can you tell from that layout picture?

[oregon_phil]

The place where they discuss "Voltage Blocking bei 20kWp SolarEdge Anlage - Strings neu aufbauen" has much more experience and many more threads regarding voltage blocking. I would suggest using Mr Google to find that thread and fully dissect it. Another thread "Solaredge - Anlage mit 3 Ausrichtungen erzeugt zu wenig Leistung" (Solaredge - System with 3 orientations generates too little power).

I cannot comment on whether or not the installer made a "mistake". Me, being a retired mechanical engineer, I would 3D model your specific home with trees, adjacent homes, etc. to see how the sun progresses over the solar panels. If you have an excellent relationship with your installer, you can get them to do this work for you. Perhaps the installer can show you the model they used to predict solar system yearly output to make sure they included trees, neighbor homes, etc. I'm not an installer, but it was my impression that Helioscope used Google Earth data to predict shading from trees, adjacent homes, etc.

[J.P.M.]

Do you think the installer made a mistake? And is it fixable?



You don't think it is? Can you tell from that layout picture?

As a P.E. (now retired) I learned to not draw conclusions until I'm confident in doing so.
From what you've provided, I don't have feel I have enough information to form a clear opinion. Call me ignorant.

My suggestion for you to ask your installer for clarification as to why he thinks all is well, or at least operating as it should under the inputs - given the apparent shade and it's seeming effect on your system's output - was so he might be able to provide information that might help you better understand how a PV system works.

From what I think I may be seeing - from afar as it were - looking at the possible shade, your somewhat apparent roof and panel orientations and your output - it looks to me that things are operating about as I'd expect. But I'm not on site and my guess is you can't provide needed information about panel orientations, tree and roof relative heights or distances or latitude that would help give me the confidence to form an opinion that has a good probability of being helpful rather than sending you off on a wild goose chase.

But maybe asking the installer to explain why he thinks things are OK will perhaps jog him to a better explanation to you how things work, and also maybe give him an opportunity to reexamine things and find something he may have missed. You also may have the opportunity to learn from the installer some things that you might better have learned about how PV operates before you bought the system.

Besides, the installer is, or at least was, on site. None of us - except you - are and this is one of those cases where propinquity counts.

Take what you want of the above. Scrap the rest.

[Woodenshoes]

Thank you. I think the design is not faulty, but could have been better.