ISO 23570 specifies the interconnection of elements in the control system of machine tools and similar large pieces of industrial automation, including cable types, sizes and sheath colours, connector types and contact assignments, and diagnostic functions appropriate to the sensors and actuators. This part of ISO 23570 specifies the interconnection of single-phase or three-phase auxiliary motors with their power source. ISO 23570 does not address the design or operation of such equipment with respect to safety issues. It is advisable that appropriate safety standards be consulted for such requirements.