Caravan & Camper Battery Charging Feedback

This may interest people not familiar with all this battery stuff. I have a Goldstream Camper and in addition to the above diagram I've also fitted into the camper a 300w inverter. Its used when 240v is not available for such as electric shaver, laptop, TV/DVD and the slow cooker. The inverter will drive the slow cooker on low setting no worries. Also for those who have campers with 3 way fridges and power them with 12v whilst driving I have the car battery 12v supply to pin 2 via a 40A relay activated by the ignition. This is so you can stop for say a walk or sightseeing and not flatten your car battery,

Hope this helps some members.