STO is a drive safety function that prevents torque-producing energy from reaching the motor without necessarily disconnecting the main power supply.
Safe Torque Off (STO) is relevant when selecting, integrating, replacing or troubleshooting industrial automation equipment. The exact engineering requirement depends on the controller, machine process, interfaces, safety requirements and maintenance strategy.
This definition is intended as a technical reference. Product compatibility, safety performance and final selection must be confirmed against the latest manufacturer documentation and the actual machine conditions.
