2.4
Safety functions integrated in the drive
Via the networked SINAMICS S120 drive, Safety Integrated supports SINAMICS Safety
Integrated Functions (Page 93). These safety functions integrated in the drive can
communicate with the process via safety-relevant input/output signals. They can be
implemented for each individual axis and spindle.
Differentiation by scope
Based on the scope of the available functions and the licensing required, a distinction is made
between "Basic Functions" and "Extended Functions":
● Safety Integrated Basic Functions are always included as part of the standard scope of the
drive, and can be used without an additional license. These functions do not require an
encoder and/or do not place any special requirements on the encoder used.
● Safety Integrated Extended Functions require an additional license (Page 51). Extended
Functions with encoder require a safety-relevant encoder concept (Page 191).
Differentiation by application
Based on the specific application, safety functions integrated in the drive can be split up into
three main classes:
● Functions for safely stopping the drive, without having to disconnect the power from the line
supply
● Functions for safely monitoring the motion of a drive
● Functions for safely monitoring the position of a drive
List of all the safety functions according to the application
Table 2-1
Functions for safe stopping and braking
Safety function
Scope
Brief description
Configuration via
Safe Torque Off
(STO)
Extended Safe Torque Off is a safety function that prevents the drive from re‐
starting unexpectedly in accordance with EN‑ 60204‑1. STO prevents
the supply of power to the motor, which can produce a torque. This is
equivalent to stop Category 0.
Basic
Safe Stop 1 (SS1,
time-controlled)
Basic
Safe Stop 1 is based on the "Safe Torque Off" function. This means
that a Category 1 stop in accordance with EN 60204-1 can be imple‐
mented.
Safe Stop 1 (SS1,
time and accelera‐
tion controlled)
Extended
Safe Brake Control
(SBC)
Basic
Extended
Safe Brake Control is used to safely control a holding brake.
1) 2)
Safe Brake Test
(SBT)
Extended The diagnostic function "Safe Brake Test" function (SBT) checks the
required holding torque of a brake (operating or holding brake).
3)
This function is in conformance with SIL 1 according to IEC 61508 and
to PLd/Cat. 2 according to EN ISO 13849‑1.
Safe Stop 2 (SS2) Extended Safe Stop 2 is used to safely brake the motor with a subsequent tran‐
sition into the "Safe Operating Stop" state (SOS). This means that a
Category 2 stop in accordance with EN 60204-1 can be implemented.
Fundamentals
2.4 Safety functions integrated in the drive
Safety Integrated (with SINAMICS S120)
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Commissioning Manual, 02/2020, A5E46305916B AB