We are starting out in irrigation installation. Won the bid for a small addition to an existing irrigation system. Its a 150x300 rectangle with coverage from RB 5004s. I am confused how to wire in the valves to be most efficient. How are we going to connect to the common without grounding out the others? (I don't remember this ever being covered in classes.) We are installing 10 zones into the backyard of a larger system that has a total of 20 zones already. Any help is greatly appreciated. Thanks!