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Ive used the mppt calculator, but with no results and my panels are not listed.
I have Trina TSM-415DE09R.08 panels, Voc 50.0v Isc 10.55A.
On my roof I can comfortably fit 5 panels and a single series string would make Voc 250v, @ Isc 10.55A, which I think a 250/70 mppt will work, or is it better to parallel all 5 panels making
Isc 52.75A @ Voc 50.0V and use a 150/70 mppt which is cheaper to buy too.
What would be the prefered configuration?
Another thought is to use 4 panels on 1, 100/20 mppt, and series- parallel 4 panels, making Voc 100V, Isc 21.1A, although the mppt is only rated atr 20A but does the mppt mean Isc or Imp (maximum power) which in my case would be 9.94A per panel, making a parallel setup with 19.88A which is still within the range of the 100/20 mppt. Then for the 5th panel I would buy 75/10 as these mppt's are a lot cheaper and i'm on a tight budget.
Would this configuration be ok?
No. Isc is out of spec. Check the datasheet for the mppt you are looking at.
The 20 refers to amps out put. You would probably be throwing power away.
Its a discontinued? panel so can kind of understand why its not in the database.
What is your system battery voltage?
You cannot use a 250v mppt for your panels of configured in one string. The VOC alone breaks the rules even without temperature coefficients.
A 450\100 rs would work if you have 48v.
You are stuck with either using 4 on the 250/70 mppt and buy a small one for the other single one. Or the 5s which could work on the 250/70. The input short circuit current limit restriction is 70A. So you would be under that.
Its a 48v system, and 5 panels will fit on just one of my two roofs. After my OP I came to realise that I could fit 10 planels on my other roof, and if I wire the 10 as two strings of 5 on the other roof then parallel them, ide have 20A @ 250v, then if I parallel those to my smaller roof of 5 in series, I would have 30A @250v, could I then use a 250/70 mppt?
I'm building an over size array, as we get so littyle sun here anyway, so full current would never really be achived anyway I wouldnt think.
