question

peterb381 avatar image
peterb381 asked

24V (series) vs 12V (parallel) charge rate with Victron 100/50 MPPT?

Hey guys, hopefully a very easy question to answer here...so assuming I had 3 solar panels putting out 15a @ 50v total - would a 24v system (Two 12v 100ah batteries in series) with a Victron 100/50 mppt charge twice as quick as the same batteries in a 12v parallel system? As in, 24 x 15 = 360w as opposed to 12 x 15 = 180w; or am I *most likely* missing something fundamentally obvious, as I'm very new to all this. As always - many thanks in advance, Peter

MPPT Controllersbattery chargingLithium Battery
2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

2 Answers
derrick thomas avatar image
derrick thomas answered ·

They would basically charge the same. The mppt takes the incoming pv and steps it down to the battery voltage. As the voltage is stepped down the amperage goes up, but the watts remains the same, that is what is going into the batteries.

Think of it like a water pipe. You can flow the same gallons of water through a smaller pipe at higher pressure as you can through a larger pipe with lower pressure.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

1234enough avatar image
1234enough answered ·

The MPPT converts the PV power to voltage of charge 12 / 24v , simple maths to work out input to output and don't forget to minus a few % for efficiency.

15a @ 50v = 750w, 750w @ 12v = 62.5a, but MPPT would limit charge to 50a as that is its max charging amperage - that is if MPPT was 100% efficient, which it isn't- hence it gives out heat/ uses or looses some power in converting.

2 |3000

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.