Jump to content

Shadows


Bobster
 Share

Recommended Posts

3 hours ago, Bobster said:

AIUI the other three panels will now drop their output to that of the two that the shadow falls on. Is that correct? 

I have 3S2P and did a test some months back where I threw a blanket over one panel (If i recall correct) only that string with the blanket were effected and the other two strings were not effected. I did the test because my fireplace chimney threw a small shadow on one panel, but my conclusion was the chimney effect was minimal.

The result might be very different with a systems that have only one string in series.

Link to comment
Share on other sites

12 hours ago, Bobster said:

AIUI the other three panels will now drop their output to that of the two that the shadow falls on. Is that correct? 

My understanding is no. The voltage of the two shaded panels will drop, possibly to zero, but the diodes in the panels will prevent them going negative. The other panels will in effect provide full output, unaffected by the shadow on two panels. By 16:00, your output will be fairly low anyway. Your output should drop to about 4/6 = ⅔ of what it would have been.

I assume that your other string is connected to a different MPPT. So it will also be completely unaffected.

Link to comment
Share on other sites

11 hours ago, Coulomb said:

My understanding is no. The voltage of the two shaded panels will drop, possibly to zero, but the diodes in the panels will prevent them going negative. The other panels will in effect provide full output, unaffected by the shadow on two panels. By 16:00, your output will be fairly low anyway. Your output should drop to about 4/6 = ⅔ of what it would have been.

I assume that your other string is connected to a different MPPT. So it will also be completely unaffected.

Yes, I didn't expect to be generating a lot at 16:00. 

This array faces northish. The other 6 panels, on a separate MMPT, are 90 degrees to this, so eastish. 

Link to comment
Share on other sites

20 hours ago, Gerrie said:

I have 3S2P and did a test some months back where I threw a blanket over one panel (If i recall correct) only that string with the blanket were effected and the other two strings were not effected. I did the test because my fireplace chimney threw a small shadow on one panel, but my conclusion was the chimney effect was minimal.

The result might be very different with a systems that have only one string in series.

Thanks. I have 6 panels on each string. I think. Certainly 6 per MMPT. 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...