The road traffic signal controller is a device that can change the order of road traffic signals, adjust the timing and control the operation of road traffic lights.
Road traffic signal system has a history of more than 100 years. The standards of road traffic signal system in European countries are moving closer to EN series standards, including EN 50556 (Road traffic signal systems), EN50293 (Road traffic signal systems - Electromagnetic compatibility), EN12675 (Road traffic signal controller) and so on.
The standard for the U.S. system is NMEA-TS1/TS2, which specifies the hardware structure of road traffic signal controller, communication protocols between boards, interface standards, and other content. The current standard for road traffic signal controller used in the United States is the NEMA TS2-2016 version, which has evolved from the earliest NEMA TS1 to NEMA TS2 in 2016, which provides a detailed description of the controller's hardware and software functions and the most basic concepts.
