Underperforming Samil Power Inverter?

Hi all,
Does anyone have a Samil Power Inverter ? (mine is a SolarRiver 4000TL-D)
My inverter appears to be limiting (clipping) to 2400 watts when it is supposed to be 4000 watts.
Puzzling thing is it only does this on some days. Even on similar full sun days (not a cloud in the sky all day) recently it has performed as one would expect on one day (up to 3500+ watts) then limited itself at 2400 for the middle 4/5 hours of a subsequent day a few days later.
While trying to track down the cause of this, I came across this screen on the inverter

Anyone know what the line saying active power 60% means? is this telling me it is limiting to 60%?
When I turned off one string (either one) I get around 1600w so I would expect to get 3200w with both strings on not the 2400w shown.

Any ideas anyone?

Thanks, Ivan

“Active power” normally means the real part, rather than “reactive power”, which was called the Imaginary part when I learned my electrical engineering. You only get useful work from the real part, but both contribute to the current flowing and hence system losses - resulting in what is called “circulating vars” (var = volt ampere reactive). If “Active power” in this case really means this, it’s saying the inverter is seeing a highly reactive load (poor power factor) and its output is probably being limited by current rather than power.

Thanks Robert, I don’t think your description fits the situation I am experiencing here though (although I may be wrong). It appears that once the inverter has “decided” that today is a “limited” day then it stays that way. That tends to suggest it is not a response to the load type (to me at least).

Today it has “decided” it is not a limited day and the display is showing 100% and lo and behold I am getting 3000+w output.

I have also noted that when it was limiting the input configuration was Parallel and today it says Independent.

I did think it didn’t mean active power in the usual sense, but it was worth putting it forward for consideration as a possibility. Based on the information you’ve added, I think I’d be looking for a way to lock it in “Independent” mode - or at least find out what the configuration options are and the implications behind the choice.