I've done some tests with mine and I'm sure it's just the inverter displaying the wrong values.
It's been cloudless today so when the output was leveling out at its peak in mid afternoon I took 3 measurements.
1 Just string 1.
2 Just string 2.
3 both strings.
When I measured output at the generation meter (which I assume is properly calibrated) then String 1 gave 1756W (inverter read 1885W!), string 2 gave 1726W (inverter read 1728W) and together they gave 3420W.
So it looks like the inverter is reading high for string 1 but really both strings are giving out about the same power.
It's been cloudless today so when the output was leveling out at its peak in mid afternoon I took 3 measurements.
1 Just string 1.
2 Just string 2.
3 both strings.
When I measured output at the generation meter (which I assume is properly calibrated) then String 1 gave 1756W (inverter read 1885W!), string 2 gave 1726W (inverter read 1728W) and together they gave 3420W.
So it looks like the inverter is reading high for string 1 but really both strings are giving out about the same power.