There are three red, yellow and green signal lights in the north and south of the intersection, and the six lights reciprocate in a certain time sequence.North-south directionNorth and South Green (8s), East and West (8s)North and South Yellow (2.1s), East and West (2.1s),North and South Red (10.1s), East Green (8s), East Yellow (2.1s)East-west directionEast-West … Continue reading PLC control ladder design of traffic lights