Can I do it?

[TommyD]

I have coming a Victron Energy SmartSolar MPPT 250/100 SCC. I have an existing string of 3 - 235 Watt Solar Panels in series with a Voc of say 70 volts and an Isc of 10 Amps . In the future, I plan on buying 6 - 400 Watt panels with 2 strings of 3 resulting in a Voc of 120 Volts and Isc of 10 Amps.
Can I basically hook up both strings to this MPPT controller, in the same positive and negative posts ie. will the MPPT SCC perceive this as a PV Array of 190 volts at 10 Amps?

 

[MisterSandals]

The 2 10A strings will be parallel strings so the amps are combined to 20A.
And combining 2 120v strings in parallel will result in 120v. (Unchanged voltage).

 

[TommyD]

OPPS!! Mislead everyone! 6 - 400 watt panels wired the way I propose produce 120 volts but 20 Amps, not 10!!

So, seems like I start with one set of panels at 2400 watts (6 x 400) and a second set of panels at 700 watts, so total of 3100 watts potential.
As everyone knows watts in = watts out. So, shouldn't I end up with 3100 watts output?

Question, what would be the input and output watts, voltage and amps when being feed into a 24 Volt Battery Bank?

 

[MisterSandals]

String 1: 6x 40Voc = 240v @ 10A

String 2: 3x 23.3Voc = 70Voc @ 10A

S1 + S2 in parallel: 70Voc @ 20A. (1400w Bad)

How about 3 equal strings?
2x 400w + 1x 235w. (Series)
80v + 23.3v = 103.3v @ 10A

S1 + S2 + S3 (parallel)
3x 103.3v @ 10A = 103.9v @ 30A (3040w good)

This would be better suited to a 150w MPPT.
How much better, i dunno. Probably not much. A Victron 150/50 probably a LOT cheaper.

 

[TommyD]

Thanks for this guidance, let me put some more thought into this,