I have recently bought a Hymer that has a Sterling Inverter fitted. It is plumbed directly into the main EHU supply via an automatic changeover switch. when on EHU the changeover selects external and when not available it looks for the inverter and if available it selects that. EHU and inverter both use the same 240 v circuit. So far so good. The problem arises when off grid and you switch on the inverter, the control panel thinks it has 240 v supply and powers all the sockets AND the on-board battery charger. So we have the leisure battery supplying the inverter that supplies the battery charger that then charges up the SAME BATTERIES that its getting its power from. To add insult to injury the control panel isn't smart enough to realise this and thinks its charging the batteries and so the AH reading goes UP and eventually says the batteries are fully charged however the battery voltage drops showing the correct level but this isn't accurate enough to give a clear picture of true battery state. Has anyone ever come across this and if so how did you get around it. Clearly it is wasting energy going around in circles and also the control panel is giving a false reading.