Luminous signalling system for railway networks, or road networks comprising • a luminous device comprising - LED lighting means , - a dissipative dummy load for increasing the electric power absorbed by the device when the LED lighting means are emitting light, - current interrupting means configured for interrupting the flow of a current in said dissipative dummy load , - driving means configured for cyclically activating and deactivating the current interrupting means ; • a power line configured for supplying power to said luminous device ; • a field controller configured for - activating said luminous device by allowing a supply current to flow along the power line , - measuring, during a sampling time interval, a value of the electric power transferred by said supply current flowing along said power line , - determining an operating state of said luminous device on the basis of said value of transferred electric power, and wherein the driving means are configured for - activating the current interrupting means , so as to allow the circulation of the current through said dissipative dummy load , before the beginning of said sampling time interval, and - deactivating said current interrupting means , so as to stop the circulation of the current through said dissipative dummy load , at the end of said sampling time interval. • a luminous device comprising - LED lighting means , - a dissipative dummy load for increasing the electric power absorbed by the device when the LED lighting means are emitting light, - current interrupting means configured for interrupting the flow of a current in said dissipative dummy load , - driving means configured for cyclically activating and deactivating the current interrupting means ; - LED lighting means , - a dissipative dummy load for increasing the electric power absorbed by the device when the LED lighting means are emitting light, - current interrupting means configured for interrupting the flow of a current in said dissipative dummy load , - driving means configured for cyclically activating and deactivating the current interrupting means ; • a power line configured for supplying power to said luminous device ; • a field controller configured for - activating said luminous device by allowing a supply current to flow along the power line , - measuring, during a sampling time interval, a value of the electric power transferred by said supply current flowing along said power line , - determining an operating state of said luminous device on the basis of said value of transferred electric power, and wherein the driving means are configured for - activating the current interrupting means , so as to allow the circulation of the current through said dissipative dummy load , before the beginning of said sampling time interval, and - deactivating said current interrupting means , so as to stop the circulation of the current through said dissipative dummy load , at the end of said sampling time interval. - activating said luminous device by allowing a supply current to flow along the power line , - measuring, during a sampling time interval, a value of the electric power transferred by said supply current flowing along said power line , - determining an operating state of said luminous device on the basis of said value of transferred electric power, and - activating the current interrupting means , so as to allow the circulation of the current through said dissipative dummy load , before the beginning of said sampling time interval, and - deactivating said current interrupting means , so as to stop the circulation of the current through said dissipative dummy load , at the end of said sampling time interval. <EOS>