Shade effect on series panels.
Pictured below is the shading on 2 of 6 series-connected panels: And this is what the controller says: So, 57.2 x 5.6 = 320w (IN) Normal (full sun) should be about 84 x 7.5 = 630w,...
Forum Discussion
So Vmp went from 95 down to 91 in the first hour (I don't know why)then held near rated Vmp till Vabs reached and MPPT stopped at noon. So each panel is doing its rated Vmp and you add them to get the total.
That's what I get with my three 100w in series--Vmp is about 52v
So what would be going on with the OP's Vmp of 85v with the controller in Bulk and all panels in the sun? The Vmp total should be higher than 85-- maybe 100?
A panel would not have 14v as Vmp except if very hot panel temp. Lower irradiance has the same as rated voltage, just lower amps and so lower watts. (IV curves for temps and for irradiance)
So I had that wrong. The controller is picking that Vmp of 85 out of whatever it "sees" but what is it seeing?
That's what I get with my three 100w in series--Vmp is about 52v
So what would be going on with the OP's Vmp of 85v with the controller in Bulk and all panels in the sun? The Vmp total should be higher than 85-- maybe 100?
A panel would not have 14v as Vmp except if very hot panel temp. Lower irradiance has the same as rated voltage, just lower amps and so lower watts. (IV curves for temps and for irradiance)
So I had that wrong. The controller is picking that Vmp of 85 out of whatever it "sees" but what is it seeing?
