Stefan Buys

We had an installation done beginning of August 2020. This installation consisted out of: 6x Canadian Solar 365W panels 2x Pylontech US2000 2.4kW batteries 1x Kodak King inverter Three days in I discovered on the inverter's display it would indicate that MPPT is present (icon visible), but it won't utilise it, power is only drawn from batteries (see attachment). After a lot of back forth with installer and distributors, which included different settngs, rewiring the panels to lower voltage, no luck. I purchased the latest ICC and started to analyse the data to try and understand the problem a little better (see attachment). What I discovered was batteries are charged via PV input during the course of a sunny morning, with little loads, reaching 99%-100% SOC. When the battery reaches this SOC, the PV input starts to "oscillate" from max to zero for several minutes, whereafter the PV input simply "drops out" (see screenshot attached). The effect is that for the remainder of the day, output is drawn from only the batteries. The only way to get the inverter to utilise the PV input again is to physically shut down and power up both the batteries and interter. I have to do this on a (near) daily basis. Inverter was booked back in for testing recently and it was confirmed that it had a faulty PV input controller. A replacement unit was installed three days ago and yesterday I noticed exactly the same issue occurring. Obviously there could be many factors that can cause this. The installer is now suggesting that I upgrade from the Kodak to a slightly more expensive Growatt unit, but is that the solution? Although I've searched this forum up and down for answers, I can't seem to pinpoint the exact problem. I am not an expert in this field and would appreciate any assistance.

I have this exact problem. It happens as soon as the batteries are fully charged, usually around midday.