1-5 inches shading cause the whole string to drop power to 16w?

[Chebamau]

Hi everyone,

I try to figure out what cause this wierd behavior around noon time where a string of 8 Panasonic 330w drop wattages from 220W to 16W for the remainder of the day. Optimizer V is around 42v around this time.

Everything run great since I installed on 6/24. Based on what SolarEdge monitoring log, issue started around 9/13.

Here is the system configuration.

SolarEdge 7600US
SolarEdge P400 optimizers
Panasonic 330w panels
2 Strings of mounting on north facing with reverse 30" title mount from iron ridge.
1 sting with 12 panels (top row of 8 and other 4 panels mount on top of the garage facing north)
Other string of 8 is bottom row.


I took a picture around 12:50pm PST to show to SolarEdge support. They said that due to 1-5 inches shading of the top row, it cause the whole string to drop power. Please advise if this is the case. Thanks.

See pictures.

[max2k]

...

See pictures.

pictures didn't come through

[Chebamau]

Pic

[kb58]

Every string in every panel in that row is partially shaded. In that case, yeah, that's what'll happen. Microconverters can only "fix" shading on a given panel by leaning on sub-strings on the same panel that aren't shaded. In this case, they all are, so... yeah. About all you can do is move all the panels vertically or to the right to get out of that shadow. The real problem is that the two rows are too close together, and the problem's only going to get worse until 21 December.

[max2k]

Pic

well, you got 'perfect' problem- every panel and every substring of cells in each panel is shaded. It also sounds like as sun goes lower moving into the winter you're going to have this problem more pronounced.

Do you have snow at your location? If so it will accumulate at the bottom cause the same shading and then water will damage your panels, I doubt they will make it till next spring in such case. Why installer didn't leave gap between roof and bottom of the panels for water to drain as even normal rain runoff has nowhere to go but on the panels?

[ButchDeal]

The solution to both problems is easy. Loosen the clamps on the modules and move them northwards,leaving a nice gap a the bottom and less shadow.

[littleharbor]

As the sun rides lower and lower into winter, the shading will worsen, possibly beyond what an adjustment can fix. Looking at the rail spacing there is about an 8" difference in the wrong direction. If you can offset the panels that far the other way you might be able to gain most /all what you will need for that magical Dec. 21st date.

[Chebamau]

Thanks. I just moved that row about a foot back and the row in front about 4-5 inches up (toward south). Hopefully that will extended a few more hours. Will see if tomorrow the power production in this string around noon again.

[AzRoute66]

Hi everyone,

I try to figure out what cause this wierd behavior around noon time where a string of 8 Panasonic 330w drop wattages from 220W to 16W for the remainder of the day.

I would like to see more pictures. It seems to me that "around noon time" is around the time where things are around as good as they are going to get. How is it that this row of panels had good production all morning long? Perhaps some more pictures with a wider angle please?

[ButchDeal]

I would like to see more pictures. It seems to me that "around noon time" is around the time where things are around as good as they are going to get. How is it that this row of panels had good production all morning long? Perhaps some more pictures with a wider angle please?

before noon the sun is to the east exposing some of the modules fully.

I would like to see the full layout including the logical layout as well though. Do you have the solaredge public monitoring site enabled?
photos showing all the arrays would help with shadow layout.

It seems that the installer made a rather serious mistake with this row though. It looks like it was planned to be further from the roof but probably at installation time a more junior person installed them shifted towards the roof. Luckily the fix is simply.

[bcroe]

Moving the panels out of the shade is the best answer. If the panels were mounted landscape instead
of portrait, the first shading would only disable 1/3 of the cell bypass groups, instead of all of them.
Bruce Roe

[Chebamau]

I do have SolarEdge monitoring. I'll see if I can enable the public view. I'm off work today so I'm planning to take some pictures at 12pm PST then some more on the next hr.

I'm still not convinced that at 12:00 pm (noon) some sort of shading will cause the string of 8 went to 16W per panel. The picture I provided taken around 12:50pm, therefore at 12pm it shouldn't have any shading.

We'll see around 12pm today.

SolarEdge phone support is painfully long. An hr wait before I can get someone on the phone. Online Chat seem to be better but harder to explain.

By the way, I did my own research and did most the install myself. I already gave about 3-4 feet apart to accommodate shading but didn't expect the shading getting worse toward year end.

[AzRoute66]

The picture I provided taken around 12:50pm, therefore at 12pm it shouldn't have any shading.

I'm betting it does (or would if left where we saw it),

We'll see around 12pm today.

You should probably get up there and take a look right now. (0900 hours). Definitely by 1000.

By the way, I did my own research and did most the install myself. I already gave about 3-4 feet apart to accommodate shading but didn't expect the shading getting worse toward year end.

There are shade analysis apps/tools out there, did you use any or just eyeball the whole shade thing?

[AzRoute66]

The real problem is that the two rows are too close together, and the problem's only going to get worse until 21 December.

Very true, and although things will start to get better after December 21, they will stay in the shaded condition until mid-March, at which time it will look much as it does today.

[ButchDeal]

SolarEdge phone support is painfully long. An hr wait before I can get someone on the phone. Online Chat seem to be better but harder to explain.

Why are you calling solarEdge? They can't help with this issue.