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hi everyone Jeff Cote here with boatingtechtalk.com we've got a question here from Othello voter uh Paul asked Jeff I've got a charge controller That's rated for Max output of 60 amps does that mean that it limits the solar cells that I can install short answer is absolutely and yes when you size a controller uh one thing you have to do first of all is ask yourself what voltage and I've done that error by the way not all boats are 12 volts some of us have 24 volts so if you've got a 24 volt bolt or a 48 volt boat DC you need to buy a solar controller that matches your battery Bank voltage so if you've got 12 volt 12 volt controller and on and on so that's the first step next actually is going to be in the data sheet is going to be the Max rated amperage that can go through that controller some controllers are also going to say the max wattage they are related but certainly amperages gives you a good clue so in this instance Paul says Jeff I have a 280 watt solar rate so a 280 watt solar array practically speaking is probably going to give at Max in terms of maybe output I would say 20 would be a lot that would be a phenomenal output out of that array it's most likely going to be between 10 and 15. so yeah the good news is Paul's controller at 60 amps can handle no problem a 280 amp uh or 280 watt solar array but don't think that all solar controls can handle all solar arrays absolutely not most controllers are rated either 10 or 15 amps right so that's a fraction that's a quarter of what Paul has on his boat so when we match controllers to solar panels either a solar panel to a controller or multiple solar panels to a controller and it doesn't matter if it's wired in parallel or it's in wired in series that solar array is still going to have an aggregate output of amperage it has a rule of thumb you could say that a 100 watt solar panel is going to Output about five six amps at the most most times you could have amazing output when the solar panels and the sun are directly above there's no shading everything is perfect you might see a little bit more than that but you know about five to six amps is what you're realistically going to get and you might Peak a little higher but you're not going to get you know 10 amps out of 100 watt panel so what you end up doing is you look at the data sheet from the solar controller manufacturer and you make sure that the max output of your solar array in terms of wattage and also amperage will not exceed the inputs that can come in to your solar controller and the other thing to remember is if you come with a high input voltage your input current might be lower obviously because in series the voltage as the ad but the current stays the same but that's all going to get translated or I.E converted to your battery voltage so you could have a solar array that's at let's say 50 48 volts 50 volts and the current is I don't know 10 amps but if your battery bank is at 24 well that conversion is going to make it 20 amps at 24. so you always got to think about not just the input voltage and input current but what is the max current that's going to happen on the controller either at the input or at the output and you worry about that and that's how you end up sizing a controller and also being realistic to not keep on adding solar panels to Only One controller assuming or hoping that that solar controller can handle anything you throw at it because assumptions on a boat rarely pan out for anyone so not worth it so yeah size your controller based on battery voltage solar wattage and total amps going out of the controller you take that all into consideration and those are generally the main requirements for sizing a controller by the way if you're curious about more solar controllers we've got tons of Articles including I've done some deep like like quite a lot of time just talking about solar controllers and there's a bunch of presentations just on that very topic so if you want to geek out well just go in YouTube and search for some topics from pys or go on our website and you'll find a lot more about selecting and choosing a solar controller for your solar rate thanks for everyone for watching and uh please submit your questions so we can geek out further so if you're curious again go on our website and find out more answers and solutions with this sort of setup and thanks for asking and thanks for all of you for listening and tuning in English (auto-generated)