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multi volt panels ?

Tired Old Man

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Multi voltage panels ?
Looking at 300 watt panels that says multi voltage. 12 volt, 24 volt, 36 volt.
It that correct ?
 
These are not multi-volt panels. They are 44.1 VOC
It states that they "DC/Charger volt compatible" which they will work with pretty well with any MPPT solar controller.
 
Yeah, it's marketing speak. There's no such thing as a "12v" panel, there's a panel that will produce enough voltage to charge a 12v system. Likewise there's no "24v" panel, just panels that create enough to charge a 24v system. That panel will produce enough for a 36v system, but isn't high enough for a 48v, so you can use it for anything 36v and down. Your controller will do the voltage modification bit out the other end.
 
Yeah, it's marketing speak. There's no such thing as a "12v" panel, there's a panel that will produce enough voltage to charge a 12v system. Likewise there's no "24v" panel, just panels that create enough to charge a 24v system. That panel will produce enough for a 36v system, but isn't high enough for a 48v, so you can use it for anything 36v and down. Your controller will do the voltage modification bit out the other end.

Actually, there are. It's a nominal voltage. 36 cell panels are "12V". 72 cell panels are "24V". These were designated as such due to the requirements of PWM chargers. A 12V battery needs a 12V panel, etc.
 

I'm sure I'm reading something wrong.

Yep. Just listing charger compatibility. Needs to be used with MPPT.

This is a split cell panel. It's basically two 60 cell panels in parallel, thus the 120 cell count. The upper half is one panel and the bottom half is a second panel. These are more tolerant of partial shading.

Worth noting that Panasonic has announced that they will exit the panel market. If future expansion is desired, these panels may not be available.
 
So I can use these on a 12 volt system with a MPPT charge controller. Will I still get the listed wattage ?
 
So I can use these on a 12 volt system with a MPPT charge controller. Will I still get the listed wattage ?
Short answer is yes. You can use these with pretty well any MPPT controller. Now, If you want a 12 volt system, just pair it with a 12 volt controller. Will you always get advertised panel wattage? Almost never with any panel. Wiring, shading, sun angle, level of battery charge, etc all play a part in getting max wattage out of a panel.
 
Yes.

370W / 14V = 26.4A of charging per panel.

1 panel would need a 30A charger
2 panels would need a 50A charger
3 panels would need an 80A charger
etc.
Not sure that we are looking at the same panels in the link but 370 watt panel @ 44.1 volts is appx 8.39 amps. You can have a wide variety of controllers from 10 amps on up to use with these panels.
 
Not sure that we are looking at the same panels in the link but 370 watt panel @ 44.1 volts is appx 8.39 amps. You can have a wide variety of controllers from 10 amps on up to use with these panels.

Controllers are rated in OUTPUT amps, not input. A 10A controller would limit that panel to about 14V * 10A = 140W.
 
Controllers are rated in OUTPUT amps, not input. A 10A controller would limit that panel to about 14V * 10A = 140W.
True but a EPEVER 10 amp Tracer can be over paneled to 390 watts on a 12 volt system. And bear in mind that panels rarely ever put out advertised wattage.
 
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True but a EPEVER 10 amp Tracer can be over paneled to 390 watts on a 12 volt system.

You'll never get more than 140W out of it. I doubt the OP wants to pay for nearly 3X the panel than he can use with a 10A controller.

OP made no mention of a desire or need to overpanel. He even stated a desire to get "listed wattage," so recommending a 10A controller only misleads the OP, fails to provide his stated outcome and does not teach him how to size an MPPT based on battery voltage.

Aren't we hear to help and not harm?
 
You'll never get more than 140W out of it. I doubt the OP wants to pay for nearly 3X the panel than he can use with a 10A controller.

OP made no mention of a desire or need to overpanel. He even stated a desire to get "listed wattage," so recommending a 10A controller only misleads the OP, fails to provide his stated outcome and does not teach him how to size an MPPT based on battery voltage.

Aren't we hear to help and not harm?
We are here to help give info/options and let him make his own decisions. Sometime someone does not even know the right questions to ask at first. By his post he is very new to the game. Also, he does not understand rated vs actual real world panel outputs.

I guess by your response to me that we should have just answered yes or no to his question. So by your answer of " yes" meaning that he will get advertised wattage, you are misleading him without giving him full disclosure of advertised vs real world outputs on panels. Even though you listed different controllers, the likely hood of him getting listed wattage would be slim due to shading, wiring, sun angle, different times of year, battery charge levels, etc.

As far as "harm", nothing I said would harm him at all. Matter of fact even though a 10 amp controller will have a max of 140 watts at a given peak solar collection time, over paneling will collect more solar in the early and latter stages of collecting energy.

I tend to think that dialog with a poster getting more information and options is the key not just giving a quick yes or no answer,
 
We are here to help give info/options and let him make his own decisions. Sometime someone does not even know the right questions to ask at first. By his post he is very new to the game. Also, he does not understand rated vs actual real world panel outputs.

I guess by your response to me that we should have just answered yes or no to his question. So by your answer of " yes" meaning that he will get advertised wattage, you are misleading him without giving him full disclosure of advertised vs real world outputs on panels. Even though you listed different controllers, the likely hood of him getting listed wattage would be slim due to shading, wiring, sun angle, different times of year, battery charge levels, etc.

As far as "harm", nothing I said would harm him at all. Matter of fact even though a 10 amp controller will have a max of 140 watts at a given peak solar collection time, over paneling will collect more solar in the early and latter stages of collecting energy.

I tend to think that dialog with a poster getting more information and options is the key not just giving a quick yes or no answer,

Wow. 10A was just the wrong answer based on OP's stated desire. You're splitting hairs and throwing up red herrings to distract from your mistake.

Just admit that you gave bad advice and used the wrong method for sizing an MPPT.
 
Wow. 10A was just the wrong answer based on OP's stated desire. You're splitting hairs and throwing up red herrings to distract from your mistake.

Just admit that you gave bad advice and used the wrong method for sizing an MPPT.

Just admit that you gave him bad advise on that he would get listed wattage from the solar panel that he listed.

Listen, I do not disagree with your list of controllers that you offered to him. I do how ever disagree with that telling an individual that he would get advertised watts on a panel without any explanation. It is just wrong, you can call it splitting hairs or not. And honestly I am not sure that over paneling with a 10 amp controller will not accomplish the very same thing in a 24 hour period vs a 30 amp controller and not over paneling. It really does not matter what he may collect with the best solar collection circumstances at a given time. It is what it will collect in a 24 hour period. As a matter of fact, I may just do some disassembly and do a little experiment to see real world results.

Here is his original question:
So I can use these on a 12 volt system with a MPPT charge controller. Will I still get the listed wattage ?
This is not a yes/no question.

Some time in the future, the poster may purchase a controller that you suggested. Then he will contact you for an answer on why he is not getting listed wattage on the panel. What will you tell him?

I will always share real world results that I have learned over the years with anyone that asks, good or dad.
 
Just admit that you gave him bad advise on that he would get listed wattage from the solar panel that he listed.

Listen, I do not disagree with your list of controllers that you offered to him. I do how ever disagree with that telling an individual that he would get advertised watts on a panel without any explanation. It is just wrong, you can call it splitting hairs or not. And honestly I am not sure that over paneling with a 10 amp controller will not accomplish the very same thing in a 24 hour period vs a 30 amp controller and not over paneling. It really does not matter what he may collect with the best solar collection circumstances at a given time. It is what it will collect in a 24 hour period. As a matter of fact, I may just do some disassembly and do a little experiment to see real world results.

Here is his original question:
So I can use these on a 12 volt system with a MPPT charge controller. Will I still get the listed wattage ?
This is not a yes/no question.

Some time in the future, the poster may purchase a controller that you suggested. Then he will contact you for an answer on why he is not getting listed wattage on the panel. What will you tell him?

I will always share real world results that I have learned over the years with anyone that asks, good or dad.
He CAN get listed wattage from the panel…
Under ideal conditions, and perfect sun angle.
He CANNOT get close to listed wattage from the panel on a 12V system with a 10A charge controller…
 
He CAN get listed wattage from the panel…
Under ideal conditions, and perfect sun angle.
He CANNOT get close to listed wattage from the panel on a 12V system with a 10A charge controller…
Thanks for the reply, I did not say that it was impossible to get it. This was my response: Will you always get advertised panel wattage? Almost never with any panel. Wiring, shading, sun angle, level of battery charge, etc all play a part in getting max wattage out of a panel.

Can he accomplish the same goal by collecting the same energy by over paneling in a 24 hour period? I am not sure but I like a challenge.
 
Many microgrid inverters use overpaneling to achieve overall constant charging.
They often deal with strings of inverters.
With a single panel, the goal is to get as much wattage into the battery as possible, and undersizing a controller won’t do that. It will limit peak charging. And have zero impact vs a 10A controller on morning/evening sun angle, or shading…
 
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