@Vassen
Appologies for not being clear i already have 12 x 400 watt Art solar panels in my current system which i will be moving onto thee Sunsynk and i want to connect them on the first mmpt. 6s 2 strings. On the second one i want to add new panel i was looking at getting 9 x 540 JA panels. Can you advise on the optimizing the second mppt. Im in Durban area thanks for you input.