PV system - Lower readings on emonpi

Hi all.

Just installed my emonpi recently and i'm pretty excited about it. Hope to share some nice dashboards very soon.

I've hook up the emonpi to a PV system i have (4,14kW), but i'm getting lower readings than te ones reported by the inverter. e.g. when reading 2200W, emonpi reports ~1300W. I also get negative readings when there's no production. Any ideia on how to solved it? I've attached an image.

Additionally you see that i'm also getting inconstant readings (very detailed in some parts and "stopped" on others)

Thanks for the support!!!

Rui