Nov 30, 2020 · Intersection controller is designed to control traffic flow and traffic lights in signalized intersections, in order to provide safe traffic. Intersection controller designates the duration of red light, yellow light, and green light. It also designates the sequence of the traffic lights.Maestro controllers have TS EN 50556 quality standard. 4 groups, 8 groups, 12 groups, 16 groups, 20 groups