Victron 150/35 mppt parallel string question

This is my first time hooking up a Victron 150/35 mppt, client has six 315 watt panels, Voc 41.95 and Isc 9.8A.
The inverter/charger is a 12 volt system, connected to 2X200Ah in parallel.
Can the strings be set up as 3S2P or is the mppt limited to one string because the output is 12 volt

Use this: MPPT Calculator - Victron Energy

Custom panel, then you can mix and match for a fact.

Thanks, looks like I was way off base.

I am all for pushing an MPPT to its limits.
In my empirical testing, (with off-orientations, dirty panels and non-ideal slopes) would suggest 150% -200% is the way to go.
That said the voltage limit must always be adhered to.
In this case, you have 6 x 315Wmpp of panels available. (1890wmpp)
The limitation of this system is that it is 12V, call it a charging voltage from the MPPT of 14V.
But the MPPT’s output current maximum is 35A.
So the maximum power the MPPT is limited to is 14V x 35A = 490W.
So even given my liberal take on overpanelling, 3 panels in series would be my best practice. (945Wmpp)
The other 3 panels are surplus and will only contribute a negligible amount due to the bottleneck effect a 12v inverter has on the MPPT output.


Client actually bought two 150/35 and one 150/45, he was thinking of using two panels each. Not being used to Victron, thought all six using a 3S2P, however, @Phil.g00 , based on what you suggested, I could use one 45A and one 35A mppt, cutting down on breakers/fuses/wiring,etc.
Hopefully, the client bought the three mppt’s at a give away price, as all the other stuff and labor will add up.

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Or go 48v … I’ve been 12v adamant many many years ago … till I ran into the exact same issue.

Vehicle, always 12v.

House/backup, 48v.

Your client could do this.
However, I assume his batteries are LA. which means they won’t last long.
So use what you’ve got, but when it gets around to replacing batteries then take @TheTerribleTriplet 's advice and upgrade to 48V.

Attaboy! I like the cut of your jib!
PS: Just mount them in a cool place with adequate ventillation…

Mine works so hard I bought a fan for warm summer months to force cool it. It sommer cools the area, the inverter too … :innocent: