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Need Help with Solar Controller Info

 
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Location: Ontario
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I am getting 4 6v lead-acid batteries and will be needing an mppt controller and pure sine wave inverter to make a small solar battery bank. My question is what is the best bang for buck mppt controller for a set up like this? The batteries are 220ah, I will be hooking them up to produce 12v dc and 440ah. I only have 2 100w panels, so I'm not sure if for example, a 10amp mmpt controller would be good for this, or would I need a higher amp output? I would like to be able to hook up more panels in the future as well.

I found this one that is like $80.


 
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That's a nice charge controller that will do most of what you want. If you want to grow your system (plan ahead), you may outgrow the 30A rating.

amps * volts = watts
watts / volts = amps
watts / amps = volts

The key is what kind of amps and volts are your panels putting out?  It should say on the back, and it'll pretty much never be exactly 12V.

Let's say it was exactly 12V and 100watts
(100W/12V = 8.33A) So you'll get 16.66 amps out of 2 identical panels, 24.99 out of 3 panels and 33.32 out of 4 panels.

So your 30A controller can handle the 3 panels at full power on a good day. I wouldn't go with 4 panels and round down as it's best to expect peaks and surges.

Take a look at the various panels and you'll see lots of different numbers that add up to the rated watts.


 
pollinator
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Steve Harvey wrote:I am getting 4 6v lead-acid batteries and will be needing an mppt controller and pure sine wave inverter to make a small solar battery bank. My question is what is the best bang for buck mppt controller for a set up like this? The batteries are 220ah, I will be hooking them up to produce 12v dc and 440ah. I only have 2 100w panels, so I'm not sure if for example, a 10amp mmpt controller would be good for this, or would I need a higher amp output? I would like to be able to hook up more panels in the future as well.

I found this one that is like $80.


I've used an eleven before and they are a decent controller. If you go that waywire the panels in series for 24 volts to take full advantage of the controller.
Cheers, David
 
Steve Harvey
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Location: Ontario
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Ideally, I would want something like this because if I ever finish my washing machine motor wind turbine, I could run 300V into one of these, since the washing machine motor is already wired at 300V. Although I am not an expert on these high voltage charges at all.

https://www.morningstarcorp.com/products/tristar-mppt-600v/
 
David Baillie
pollinator
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Steve Harvey wrote:Ideally, I would want something like this because if I ever finish my washing machine motor wind turbine, I could run 300V into one of these, since the washing machine motor is already wired at 300V. Although I am not an expert on these high voltage charges at all.

https://www.morningstarcorp.com/products/tristar-mppt-600v/


Not that one it will fry. If you will eventually be using wind the midnight solar classic is the way to go but its serious money...
 
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