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businessjett avatar image
businessjett asked

2 x 350w 12v flexible solar panels

Hello

I am about to buy 2 x 350 12v solar panels for my boat to charge my house batteries.

2329b34d-7990-4747-bd77-a00f3ccea135.jpegI have no idea what I am doing but I assume I need to buy a regulator & would also like a shunt.


should I just buy the biggest regulator Victron sell ?

I’ve been caught a few times with flat house batteries so I want to get lots of solar to keep them charged & charge them fast when flat.


my boat is a 27ft sea ray. It currently has 2 x 100ah house batteries but I will probably upgrade these as well .


I have read about working out how many amps the boat uses by testing everything 1 by 1 . But not done that yet. Should I do that first ? Or just get lots of big stuff?

Thanks

Byron

solar sizing
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2 Answers
Paul B avatar image
Paul B answered ·

2 x 350 watt panels is 700 watt total or around max amps 35amps so a MPPT100/30 would do you fine, the MPPT has a inbuilt shunt for measuring solar outputs. if you want a shunt to measure ALL power in and out of the batteries then a Victron smart shunt 500 amp would be the one.

both units outputs ect can be viewed via bluetooth

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JohnC avatar image
JohnC answered ·

Hi @businessjett

Try using this calculator.. https://mppt.victronenergy.com/#

You'll note that the recommendations change depending on battery V, which you haven't stated.

It's difficult to suggest something for your future, but with mppts you can always add another as needed when you add panels. This can also help with dealing with selective shade and mismatched panels.

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