3.7.3
Safe Stop 1 (SS1)
What is the effect of the SS1 safety function?
The inverter with active SS1 function initially brakes the motor and then prevents energy being
supplied to the motor.
As a consequence, the SS1 function reduces the kinetic energy of electrically driven machine
components to the lowest possible level.
The principle of operation of SS1 differs depending on whether you use SS1 with basic
functions or with extended functions.
SS1 of the basic functions
Table 3-4
An overview of the principle of operation of SS1, selected when the motor is rotating
Safe Stop 1 (SS1)
Standard inverter functions linked
with SS1
1. The inverter identifies when SS1 is selected via a fail-safe
input or via PROFIsafe.
---
2. SS1 starts a safety timer T.
The inverter signals "SS1 is active".
The inverter brakes the motor along
the OFF3 ramp.
3. After the timer expires, the inverter safely switches off the
motor torque with the STO function.
The inverter signals "STO is active" via a fail-safe digital out‐
put or via PROFIsafe.
---
6SHHG
6HOHFW66
66LVDFWLYH
672LVDFWLYH
STO
SS1
W
W
W
W
7
Figure 3-3
Principle of operation of SS1 of the basic functions
6HOHFW
66
66LV
DFWLYH
672LV
DFWLYH
6723
Description
3.7 An overview of the principle of operation of the safety functions
Safety Integrated - SINAMICS G110M, G120, G120C, G120D and SIMATIC ET 200pro FC-2
36
Function Manual, 01/2017, FW V4.7 SP6, A5E34261271B AD