A little help with terms please

313hermit

New Member
Joined
Oct 12, 2021
Messages
3
Hi Everyone,

Definitely new to this, but I've been researching for a few months and don't understand what "Max. PV Input Current" means. I have attached the page from the user manual. I have the Growatt SPF 5000 ES and 10 365 w panels. I also added the spec page for the panels. My question is, if I have the 10 panels in 2 S5 strings and then parallel them to the inverter, I would get Voc 236.8 (5*47.36) with 19 amps (2*9.5) is this correct? If the manual says the max pv input current is 18A, does this mean I'm technically sending too many amps to the inverter? I'd like to add more panels in the future to reach the 6k limit but if I'm limited to only 18A input that seems a bit difficult. Or is this the max per panel? Would adding a combiner box help, I don't understand which amperage would leave the combiner box if I have 4 sets of 5S panels all going to one box (assuming i get the same panels), is the amperage leaving 19 amps, or does the combiner box add the amperage together, sending 38 amps to the inverter? Any help is appreciated.


1636486202138.png






1636486181375.png
 

sunshine_eggo

Happy Breffast!
Joined
Oct 26, 2021
Messages
5,933
Location
HBR, USA (6500' in ENE AZ)
Your array will have a max current it can send to the controller.

That unit is designed for large series strings with it's 450V input limit, hence the relatively low current limit of 18A.

Your panel's short circuit current is in the 9-10A range. You could parallel two strings on one input, but any current over 18A will be wasted and unavailable for charging/loads. That means that at peak solar, when your panels can actually deliver their maximum power, you might lose 10% of that capacity because the controller can't use it.

It's rare that this will actually compromise your array's output since peak output is pretty rare in most cases.

I wouldn't hesitate to put a 8S2P array of those panels on that unit for a ~6kW array.
 
Top