Siemens SINAMICS G120 Operating Instructions Manual page 307

Figure 8-72
When SS1 is activated, the following actions are performed by the inverter:
1. Both shutdown paths initiate a controlled safe brake ramp function, including detecting
2. The motor is slowed down by the safe brake ramp function.
3. The status LED SS1 starts flashing.
4. When the minimum speed for standstill detection is reached, the STO function is
5. The mechanical brake (if fitted) is closed.
6. The status LED ES is switched on.
The SS1 function can be interrupted by either an OFF2 command or the STO function.
When SS1 is deactivated before the "minimum speed for standstill detection" (P9682/P9882)
is reached, the following actions are performed by the inverter:
1. The monitoring of the actual speed is deactivated.
2. The drive accelerates to the set speed
3. The status LED SS1 changes from flashing to on state.
Control Units CU240S
Operating Instructions, 11/2006, A5E00766042B AA
Safe Stop 1 (SS1) function
the speed of the motor.
activated.
Functions
8.18 Fail-safe functions
8-111