We have a Multiplus ll inverter/charger coupled to a Solis PV inverter. When the batteries are full the frequency rises until the Solis switches off. It then takes a long time to reduce the frequency again. The issue here is that we also have a MY PV Thor immersion controller, that dumps to the immersion based on frequency. When the PV inverter is OFF, because the frequency is still high, the THor draws power from the Multiplus and overloads it. How do I get the Multiplus to reduce the frequency sooner ? The instructions tell me that the battery voltage needs to reduce to 5.2 volts below the float setting ! In this case the float is 54 volts so 48.8 by which time the DC solar charging will be active keeping the battery volts higher.