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MPPT Controler question

Rinot you are correct, you want to keep your battery bank at 24v so you can power your inverter. From what I see you could put your 4 panels in series and run the 87v into you charge controller. Your charge controller will reduce the voltage and charge the 24v battery bank.
I hope I understood your question correctly.
 
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Thanks for the input, unfortunatly I live in the northeast that does get cold,
I do have one question you said keep the four panels on one string in parrallel at there rated voltage 21.6 voc to the controller?
I will need to keep battery bank at 24VDC, that is what my inverter rated input is. It is none switchable.
Thank you,
My apologies, I forgot about your 24volt inverter. I'm so used to seeing all in ones around here.

Do the 24v battery, and do your panels as 2s2p. You will stay within any cold weather voltage increase limits.

edit.. I had this one confused with another thread where there were 6 panels.. he only has 4 panels. ?
 
Those are 195W panels, not 200W. They are also very expensive ($1/W). Do you already have them? You can easily find panels closer to $0.50/W.

They don't even list all of the specs. They don't show the Vmp. You can calculate the Vmp since W = Vmp x Imp. Assuming what they list as Iop is really Imp then 195W / 9.02A = 21.62V. But that can't be right. Voc is 21.6V. Vmp is always about 80% of Voc. So what they list as Voc is really the Vmp. Voc should be more like 26.6V. Another reason to avoid these panels if you don't have them already - they can't even post the correct and full specs.

If you already have them then they will work. The max PV input voltage of the SCC is 105V on a 24V system. If my calculations about the specs are correct, then you can't put the panels in 4S, you must put them in 2S2P. At 4S the Voc would be 106.4V. That's too high.
 
Those are 195W panels, not 200W. They are also very expensive ($1/W). Do you already have them? You can easily find panels closer to $0.50/W.

They don't even list all of the specs. They don't show the Vmp. You can calculate the Vmp since W = Vmp x Imp. Assuming what they list as Iop is really Imp then 195W / 9.02A = 21.62V. But that can't be right. Voc is 21.6V. Vmp is always about 80% of Voc. So what they list as Voc is really the Vmp. Voc should be more like 26.6V. Another reason to avoid these panels if you don't have them already - they can't even post the correct and full specs.

If you already have them then they will work. The max PV input voltage of the SCC is 105V on a 24V system. If my calculations about the specs are correct, then you can't put the panels in 4S, you must put them in 2S2P. At 4S the Voc would be 106.4V. That's too high.
Actually they're fairly decent panels, expensive yes but if you're only buying a couple the free shipping makes up for it a bit.
Eco Worthy is dismal when it comes to specs but here's the back of a panel sticker:
solar panel specs.jpg
 
Eco Worthy is dismal when it comes to specs but here's the back of a panel sticker:
Thanks for the real specs. That's much better.
Voc is 21.6V (they got one right). Vmp is 18V. Imp is 10.83A, and Isc is 11.89A.

Now that we know that Voc really is 21.6V that means 4S will work as an option since that would be a total of 86.4V. Though these panels have a large Voc temperature coefficient. A 4S panel array would exceed the 105V limit if you live in a place where it can get down to -25.ºF/-31ºC.

That's 3 panels in series more commonly written as just 3S. The 1P isn't typically written since there is only one string.

For 4 panels you have 3 total options. 4P, 2S2P, and 4S.

In your case you can't do 4P because the voltage is too low - it won't be high enough to charge your 24V battery (which will be more like 28.4V while charging).

4S will work for you as long as it never gets below -25ºF/-31ºC.

2S2P is also an option. Take 2 panels and connect them to each other in series. Take the other 2 panels and connect to each other in series. Now take those two strings and them them together in parallel. That's 2S2P.
 
Actually they're fairly decent panels, expensive yes but if you're only buying a couple the free shipping makes up for it a bit.
Eco Worthy is dismal when it comes to specs but here's the back of a panel sticker:
View attachment 104608

Hmmm.. he might be able to do those 4 panels in series, even with cold weather if we go off the controllers hard limit of 190voc and not the 105v limit it says for 24v batteries.
 
Hmmm.. he might be able to do those 4 panels in series, even with cold weather if we go off the controllers hard limit of 190voc and not the 105v limit it says for 24v batteries.
4S works even with the 105V limit as long as the temperature stays above -25ºF/-31ºC.
 
4S works even with the 105V limit as long as the temperature stays above -25.ºF/-31ºC.

That is a pretty darn low temperature. The controller also mentioned a maximum 190vdc input on the controller.. which isn't listed on the 36v or 48v battery setting.. think it would blow up the controller at 24v battery setting even if it did hit over 105v? Inquiring minds want to know!
 
I agree with rmaddy since there is a question with the voltage of the panels then wire your panels in 2 parallel and then series those with the other 2 panels in parallel (2s2p)
The voltage is too close to take a chance of burning up a controller
 
The controller also mentioned a maximum 190vdc input on the controller.. which isn't listed on the 36v or 48v battery setting.. think it would blow up the controller at 24v battery setting even if it did hit over 105v?
This is why I stay away from this cheap junk. Confusing specs. Most SCCs have one max PV input voltage no matter the system voltage. With this one I would stay under the 105V limit just to be safe.

I agree with rmaddy since there is a question with the voltage of the panels then wire your panels in 2 parallel and then series those with the other 2 panels in parallel (2s2p)
Given the actual photo of the panel's label, we now have the real specs. 4S will work as well as 2S2P.
 
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Gents, Thank you, Yea already bought all componets, Its interesting the PowMr 60a had a ton of good reviews. and was not cheap.
 
Gents, Thank you, Yea already bought all componets, Its interesting the PowMr 60a had a ton of good reviews. and was not cheap.

It seems to be pretty versatile according to the specs. Best of luck, let us know how it goes.
 
The PowMr 60A is listed at $105. That's cheap for a 60A SCC. For comparison, middle-tier Renogy has a 60A controller for $370 and a top-of-the-line Victron 150V 60A SCC is $540.

I'm not saying you won't regret buying it. I'm just saying it's a low end SCC with confusing specs.
 
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