String Sizing
I have 8x 475W Jinko Solar Panels that I want to connect to the 2nd MPPT controller on my Sunsynk 8Kva inverter. The panels have the following Specs.
VOC: 52.24V
VMP: 43.38V
NOCT: 45+-2°C
VOCT: -28%/°C
Considering the temperature coefficient (VOCT) the voltage change per degree is 0.14627V.
If I take the Nominal Operating Cell Temperature (NOCT) and take the coldest day in the year in my location ..
let say -3°, I get a temperature difference of 48° (NOCT + Coldest Temperature).
Multiply the Temperature difference with the voltage change per degree each panel will produce 7.02V above its rated VOC of 52.24V.
That is 52.24+7.02=59.26v that will be produced per panel on that cold day (-3°).
So for 8 panels in series the VOC on the coldest day will have a total voltage of 474V.
The maximum DC input voltage for the 8kva Sunsynk inverter is 500v (according to the manual). In some of Keith 's videos he recommends 450v max. Considering a perfect scenario (no losses), is it safe to say the 474v from my 8 panels will not blow the inverter?
Calculations based on info from unboundsolar.com. (String Sizing Guide)
I think you need to do your calcs on the VMP not the VOC ???
Data sheet says VMP NOCT is 33.1V so you are nowhere near,
MAX rating for the inverter is on VOC so 8x52 = 416v. Which is fine.