I have two Q.PLUS L-G4.2 335 Watt Poly Solar Panels rated at 9 amps. They are in series charging a 12-volt Lifepo4 system. The Victron shows 20 amps on the battery side, How is that possible?
Thank You
Mcomo
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I have two Q.PLUS L-G4.2 335 Watt Poly Solar Panels rated at 9 amps. They are in series charging a 12-volt Lifepo4 system. The Victron shows 20 amps on the battery side, How is that possible?
Thank You
Mcomo
Because 670W / 12V = 55,8A and the MPPT 100/20 is limited to 20A charging current.
You "waste" 35,8A (430W) in your setup.
P = U / I
With a higher voltage you need a lower current for the same power.
Your panels have 37,33Vmpp -> 74,66 for two in series and 8,97A
74,66V x 8,97A = 669,7W / 12V (battery voltage) = 55,8A
To use all the power from your panels you need a bigger MPPT. (100/50 maybe)
Also look here:
https://community.victronenergy.com/questions/120839/not-getting-close-to-max-wattage-from-solar-panels.html
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