Safe Torque Off (Sto) - Siemens SINUMERIK 828D Function Manual

Description of Safety Integrated Basic Functions

2.1 Safe Torque Off (STO)

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
Example
After an Emergency Stop button has been
pressed, the drive must be braked as quickly
as possible and transitioned into STO.
A central Emergency Stop button ensures that
several drives are braked as quickly as
possible and transitioned into the STO state.
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.
12
STO
Possible solution
Wire the Emergency Stop button with a fail-safe
•
input.
Select STO via the fail-safe input.
•
Evaluating an emergency stop pushbutton in a
•
central control.
Function Manual, 07/2012, 6FC5397-3EP40-3BA0
Safety Integrated