You need a controller. You also need to make sure you have the right kind of plug going from the controller to your RV. If they are dissimilar, you will need to buy an adapter. My last camper had a zamp solar port and my new camper has a furion port. I have a 200w zamp suitcase solar setup so I needed to buy the adapter and then I had to make sure the positive and negative were wired correctly on my RV. In my case, I had to switch the wires to work with the adapter correctly so I would also suggest you know which wires from the port in your camper goes to which terminal on your battery.