Learn about Safety Integrated Functions in Servo Drives

Read this article to learn about basic and advanced Safety Integration Functions used in Servo Drives and Controls. The article covers core, safe stop, and monitoring safety functions, as well as networking safety options
June 1, 2026

Before the 1990s, most safety precautions were handled by external hardware such as contactors, relays, and switches. Emergency stops were used to physically remove power from drives and controllers.  In 1998, the IEC 61508 standard for Functional Safety was released for electrical systems. This provided standardization for safety concepts and laid out the groundwork for more technological advancements in safety.   Servo drive manufacturers began implementing these changes, which led to the development of additional functions, including core functions (STO) in the 2000s and safe stop and speed functions (SS1, SS2, SOS, SLS, SLP, SDI) in the 2010s.  Networked safety solutions and programming were also being developed and implemented. Fieldbus solutions were created to allow these safety functions to be easily programmed.  This article examines the safety functions and networking options that make machines safer to operate, easier to prevent accidents, and easier to maintain.