Safety Functions; Overview - Siemens SINAMICS G120 Operating Instructions Manual

5.12

Safety functions

5.12.1

Overview

Functional safety
Machine components operated by electrical drives are intrinsically hazardous. If a drive is
incorrectly used or acts in an unexpected manner in the event of a malfunction, not only can
this damage the machine but it can also cause severe injury or death. Functional safety
reduces this risk of accidents caused by machines to an acceptable residual risk.
Integrated safety functions in SINAMICS G120
The CU240S DP-F and CU240S PN-F Control Units feature a range of integrated safety
functions, which are certified in accordance with Cat. 3 to EN 954-1 and SIL 2 to IEC 61508:
Table 5- 89
Abbreviation
STO
SS1
SLS
SBC
Basic prerequisites for using fail-safe functions
1. The machine risk assessment (e.g. in compliance with EN ISO 1050, "Safety of
2. The speed control of the inverter must function perfectly. Each fail-safe drive (drive =
3. Once the machine has been successfully commissioned, you must review the typical
CU240S and CU240E Control Units, FW 3.2
Operating Instructions, 03/2009, A5E02440075B AA
Integrated safety functions
Description (DE/EN)
Sicher abgeschaltetes
Moment
Safe Torque Off
Sicherer Stopp 1
Safe Stop 1
Sicher begrenzte
Geschwindigkeit
Safely Limited Speed
Sichere
Bremsenansteuerung
Safe Brake Control
machinery - Risk assessment - Part 1: Principles") allows the use of inverter safety
functions in accordance with SIL 2 or category 3.
inverter + motor + brake + driven machine) must be set up in such a way that all
operating procedures performed by the driven machine can be properly monitored and
that the inverter operates below its limit values (for current, temperature, voltage, etc.).
The performance and parameters of the inverter must be compatible with both the
connected motor and the application in question.
operating conditions and operate the machine close to the permissible limit values. The
fail-safe drive must not malfunction under any circumstances.
Function
The motor is switched safely to zero torque.
The motor is brought to a controlled standstill.
The speed of the motor is restricted in a controlled manner.
The motor holding brake is safely controlled.
Functions
5.12 Safety functions
195