I have a MultiPlus-II 48V 3000 35Amp unit installed on my boat. I don't currently use the inverter and nothing is wired into either of the AC outputs. I only use it to charge the 4 off 200Ah LiFePo4 batteries. Recently, when switching on the charger, the "Mains On" light will flash until the unit has synchronised, the "Mains On" light then goes steady and the "Bulk" light comes on for about 5 seconds, after which the Inverter "Overload" light comes on and the the other 2 charger lights go off. The unit shuts down. As I said at the start, there is nothing wired to the inverter outputs so why is the Inverter Overload light coming on? I should state that the batteries were pretty well fully charged when I did this. Not had a chance to try it again with partially discharged batteries. Anyone else had this issue?