SOTECA ELECTRIC offers three types of traffic lights management systems driven by communicating controllers and installed around PLCs. The advantage of these controllers is that they can be connected via a GPRS network to a data server or a control room to ensure the supervision or total control of these traffic lights. They are also equipped with a touch-sensitive control panel mounted on the inner door of the controller allowing quick access to set parameters and modify operating cycles. The three types are as follows:
Standard traffic lights
This classic control system allows the definition of several operating cycles. The cycle period is then predefined according to the traffic channels and their load rate. The transition from one cycle to another is automatically managed by setting the transition periods.
Dual function lights with countdown timer
This classic control system, to which counters have simply been added, offers the advantage of providing the vehicle with the possibility to move safely and to have an overall view of the traffic signal on the length of time spent at the green light and the length of time spent waiting at the red light.
Traffic light with sensor
This traffic light management system is equipped with vehicle presence sensors which are cameras that can detect the presence of a vehicle or a group of vehicles on the roadway towards which it is directed. Its role is to transmit to the PLC, installed in the controller, information about the vehicle occupancy in the roadway. The PLC will then be able to adjust the cycle to extend the green light if the channel is still occupied by vehicles or to move to the next channel if there are no more vehicles in that channel. The advantage of this technology is that it minimizes the waiting time and maximizes the flow of vehicles at the green light. This benefit has a direct impact on the improvement of the traffic speed of public transport vehicles and especially on the reduction of CO2 emissions.
Since it also measures the number of vehicles, this system shows us traffic density statistics at intersections, i.e. the number of vehicles that travel in any given lane at specific time intervals or at specific times.