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How should I wire these 10 panels for a 250V 100 A charge controller?

marcfest

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Mar 18, 2022
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I've got ten solar panels with the specs shown below and a 250V / 100A Victron charge controller.

What's the best way to wire the panels? I was going to connect them all in series but I suppose that would exceed the 250V limit of the controller.

Thank you for your help.

Marc

Charge controler:

Panels:

PANEL SPECS
Watts (STC) 345W
Max Power Voltage (VMPP) 33.37 V
Max Power Current (IMPP) 10.34 A
Open Circuit Voltage (VOC) 41.0 V
Short Circuit Current (ISC) 10.92 A
Max System Voltage (UL) DC 1000 V
 
5S2P would be best. That would put Voc at 205V at STC. You will reach 250V at about -54ºF/-48ºC (so you should be good).

All 10 in series would cause your SCC to let all of the magic smoke out. 410V is a bit too much. :)

What's your battery voltage? You're fine at 48V. You're 25% over paneled at 24V. 12V is right out.
 
5S2P would be best. That would put Voc at 205V at STC. You will reach 250V at about -54ºF/-48ºC (so you should be good).

All 10 in series would cause your SCC to let all of the magic smoke out. 410V is a bit too much. :)

What's your battery voltage? You're fine at 48V. You're 25% over paneled at 24V. 12V is right out.
Thank you, rmaddy :) I've got 4 Battleborn 12V 100 Ah batteries currently wired 2S2P...
 
OK, so a 24V system. You should be fine with the over paneling. It will help a lot in lower light conditions. But the most you will get at any one time is about 2720W and you will have 3450W. That's 80% and that might be about all you'll ever get anyway.

If you want to take full advantage of all 3450W then you might be better off with two 250/60 charge controllers and put 5 panels in series to each one. It will certainly cost more. Though you might save a bunch with a different setup. Perhaps 6 panels in 3S2P on a 150/70 and 4 panels in 2S2P on a 100/50. Lots of options. If the 2720W is more than enough and you are happy to get that more often in lower solar conditions then sticking with the one 250/100 works.
 
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OK, so a 24V system. You should be fine with the over paneling. It will help a lot in lower light conditions. But the most you will get at any one time is about 2720W and you will have 3450W. That's 80% and that might be about all you'll ever get anyway.

If you want to take full advantage of all 3450W then you might be better off with two 250/60 charge controllers and put 5 panels in series to each one. It will certainly cost more. Though you might save a bunch with a different setup. Perhaps 6 panels in 3S2P on a 150/70 and 4 panels in 2S2P on a 100/50. Lots of options. If the 2720W is more than enough and you are happy to get that more often in lower solar conditions then sticking with the one 250/100 works.
Hello I am new to this but have made a small setup. Why would he get more (3450watts) from using 2 charge controllers versus the 2p5s going into the 1 SCC? Im asking because I want to make sure I take advantage of all my panels capacity.
 
Why would he get more (3450watts) from using 2 charge controllers versus the 2p5s going into the 1 SCC?
It's the difference between one 250/100 SCC versus two 250/60 SCCs.

On a 24V system (assume a voltage of 28.4V) the 100A SCC can handle up to 100A x 28.4V = 2840W. The two 60A SCCs can handle up to 120A x 28.4V = 3408W.
 
It's the difference between one 250/100 SCC versus two 250/60 SCCs.

On a 24V system (assume a voltage of 28.4V) the 100A SCC can handle up to 100A x 28.4V = 2840W. The two 60A SCCs can handle up to 120A x 28.4V = 3408W.
ahhhhhhhh thank you for that explanation! I thought if the total voltage and amps of the panels were under the 250/100 it just took it all so thats why I was confused.
 
I thought if the total voltage and amps of the panels were under the 250/100 it just took it all so thats why I was confused.
The Victron naming convention is max PV voltage in / max SCC output current. So the two numbers are one input and one output. The panel array current has nothing to do with that second number.
 
The Victron naming convention is max PV voltage in / max SCC output current. So the two numbers are one input and one output. The panel array current has nothing to do with that second number.

Thanks for your post the current thing was confusing me. I thought it was max input current from the panels into the controller

So how do you know how many arrays you can run in parallel without overloading anything?

Thanks!
 
So how do you know how many arrays you can run in parallel without overloading anything?
Look at the spec sheet for the Victron SCC. It will show a value for "Max. PV short circuit current". Keep your array Isc under that value. Exceeding it can damage the controller.

Also note that, like Voc, the Isc of a panel changes a bit with temperature. But it's the opposite. Isc goes up with higher temperatures and Isc goes down with lower temperature. But the effect isn't nearly as much as with Voc.
 
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