Siemens SINAMICS G120 Function Manual page 172

Operation
6.3 Safe Torque Off (STO)
Case 2: Response of the drive for STO of the extended functions
You have selected the extended functions via onboard terminals.
Figure 6-9
The inverter does not set the error bit of the safety functions (= internal event).
After the tolerance time has expired, the inverter signals the discrepancy (fault C01770 or
C30770).
Case 2: Switching on the motor after a discrepancy
Procedure
To switch the motor on again, proceed as follows:
1. Remove the discrepancy.
2. Acknowledge the discrepancy message with a fail-safe acknowledge signal via a safety
input: F-DI = 0 → 1 → 0.
Alternatively: Power on reset.
3. Acknowledge the inverter with the "standard" acknowledge signal.
4. Issue an OFF1 command (ON/OFF1 = 0).
5. Switch on the motor (ON/OFF1 = 1).
You have acknowledged the discrepancy message, and switched on the motor again.
172
Response of safety function STO in the event of a discrepancy
Safety Integrated - SINAMICS G110M, G120, G120C, G120D and SIMATIC ET 200pro FC-2
Function Manual, 04/2014, FW V4.7, A5E34261271B AA