Siemens SINAMICS G120X - Safe Torque Off Safety Function

4.2.8 "Safe Torque Off" safety function
Overview
The "Safe Torque Off" (STO) safety function can be implemented using a failsafe digital input
of the converter.
Requirements
● Both switches on the converter for enabling/disabling STO are in the ON position.
● The higher-level control system monitors the selection of STO and the feedback from the
converter.
Application examples for "Safe Torque Off" (Page 132)
Function description
Use an SELV or PELV power supply with 24 V DC (20.4 V … 28.8 V, maximum 60 V briefly).
Use a shielded cable with the following properties:
● Cable length ≤ 30 m
● Cross section 0.5 mm
2
… + 1.5 mm
2
(20 … 16 AWG)
● Insulated for 600 V
● Conductor end sleeves, stripping length 7 mm
Tightening torque: 0.2 Nm (2 lbf in)
Wiring
4.2 Control interfaces
SINAMICS G120X converter
128 Operating Instructions, 06/2019, FW V1.01, A5E44751209B AC