this might be helpful for someone sent this e mail to Allan Evans of www.aandncaravanservices.co.uk/ Hi Do you have a LR1218 in stock?I have just fitted a 100w solar panel to my LR1218 which is plugged into a EBL99.I am getting about 17v from the solar panel disconnected but when I get it connected there are no extra amps on the analogue displays or volts.The weather at the moment is very overcast and grey skies. On the schaudt LR 1218 there is about 12v from the solar panel terminals when the solar panel is disconnected is this normal.I have used the LR1218 set up for years with a 40w portable solar panel no problem. Do you think it is a LR 1218 that is faulty if so how much is a new one with express Got this helpful reply Hello 17v is very low, I would expect nearer 21v open circuit? Yes all Solar regulators discharge the battery into the Solar panel, they have 'blocking resistors' which reduce the current drain to just milliamps but don't stop it completely. You will see some voltage if the battery is connected. The LR1218 has one of the lowest drains we have seen but you can fit a Voltage sensitive relay on the Panel side to break the connection altogether. This time of year and Weather I would not expect much more than about 0.25 A from 100watt. Therefore hard to know if your Panel is faulty or not. Suggest you test on a Sunny day and you might see 0.5A around midday? If there is a fault and the panel is only putting out 17v, my money would be on the Panel. Sorry don't do Solar power any more, we have seen a lot of failures and Panels down to about 50% output after just 2 years. Kind regards, Allan.