Safety Integrated Basic Functions; Safe Torque Off (Sto) - Siemens SINUMERIK Series Function Manual

2.2

Safety Integrated Basic Functions

2.2.1

Safe Torque Off (STO)

Definition
Definition according to EN 61800-5-2:
"The STO function prevents energy from being supplied to the motor, which can generate a
torque."
Select STO
Examples of how the function can be used
● This function is always active after an Emergency Stop.
● If, in the setting-up mode with open protective door, the spindle is to be manually rotated.
How does STO function in detail?
The inverter detects the selection of STO using a fail-safe input. The inverter then safely
switches off the torque of the connected motor.
Safety Integrated
Function Manual, 10/2015, 6FC5397-3EP40-5BA3
STO
Overview of Safety Integrated functions
2.2 Safety Integrated Basic Functions
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