Need some help with an issue. I have a MUST 5 kW hybrid inverter (this is probably a Voltronic white labelled inverter) and its MPPT range is 64-130 V, 9 x 375 W Fivestar solar panels connected with 3 strings (so 3 x 3), and 4 x 200 Ah Gel batteries. I noticed earlier this year (as I can monitor the system remotely via a WiFi card setup) that randomly, the PV voltage spikes to between 125 and 131 V. When this happens, the charge power from the PV drops to 150 W odd and the charger current to 3 A. This can happen randomly during the day and can sometimes stay at these levels for up to an hour or so and hence the load is not being fulfilled by the solar even though there is plenty of sunlight. Does anyone know how to resolve this issue? I understand the PV is going to the top of the MPPT range but how do I prevent it from doing this. It seems much worse now i.e. its happening more often than it was earlier in the year.
Do I need to reconfigure the setup of my panels to a different combination to reduce the PV voltage etc., or what do I do to maximize production without the voltage spiking and effectively killing the charge power? I am not super technical so would appreciate a layman response on this.