This International Standard provides rules for the composition of designations and names for the identification of signals and signal connections. This includes the designation of power supply circuits. The standard is applicable to all types of signals within an industrial system, installation and equipment. The standard is not applicable for the identification of wiring, terminals and other hardware for connections. The standard does not establish rules for • the graphical/physical representation of a signal on devices, nor • the graphical representation of signals in documentation.