Siemens SINAMICS S120 Function Manual page 401

Description of functions
With two SIGUARD safety combinations for emergency stop and the protective door, as well
as a standard PLC, the system can be configured according to EN 954-1 category 3, ISO
13849-1 and EN 1037. The drives are brought to a standstill in accordance with stop
category 1 to EN 60204-1:2006.
● The "Safe Torque Off" safety function, which is integrated in the drive, complies with
● Safety combinations for emergency stop and protective door monitoring comply with
● The electric circuits for emergency stop and protective door monitoring are monitored for
● Switches S4, S5, and S6 are positively-opening position switches corresponding to EN
● Being a higher-level circuit with contacts, the "Safe Stop 1" (SS1) function also works if
● I/O communication via the digital interface between the drive and PLC can also be
● This application example is based on the Basic Functions "Safe Torque Off" (STO) and
Behavior for Emergency Stop
An emergency stop is triggered by the S3 button ("Emergency stop"). The drive is brought to
a standstill in accordance with stop category 1 of EN 60204-1:2006.
● Open the safe enable contacts of the safety combination A1. This activates the "Safe
● The confirmation from the safety combination and the drive is monitored in the PLC to
Drive functions
Function Manual, (FH1), 10/2008, 6SL3097-2AB00-0BP5
category 3 to EN 954-1/ ISO 13849-1 or SIL 2 to IEC 61508. The non-safe checkback
signal "Safe Torque Off active" is sufficient.
category 4 (instantaneous enable circuits).
cross-circuits on two channels.
1088.
the PLC malfunctions or fails.
replaced by non-safe standard communication (e.g. PROFIBUS).
"Safe Stop 1" (SS1).
The speed ramps and speed thresholds are monitored in non-safe mode.
Note
To implement the EMERGENCY STOP function, the converter does not necessarily have
to be electrically isolated from the line supply by means of electromechanical switching
devices in accordance with EN 60204-1:2006. When work is carried out on the motor or
drive converter, the voltage must be disconnected via a main circuit breaker (that can be
locked out). Other standards (e.g. NFPA79-2002 / USA) specify additional requirements
regarding the "EMERGENCY STOP" function. An electromechanical disconnection of the
supply voltage is required to implement the "EMERGENCY OFF" function in accordance
with EN 60204-1:2006. The risk analysis to be carried out by the machinery construction
OEM must determine which emergency functions (emergency operations) are actually
required for a specific application.
Stop 1" drive function on two channels via terminal X122.2 (DI 1) on the Control Unit and
terminals X21.3 (EP +24 V) and X21.4 (EP M) on the Motor Module. "Safe Torque Off" is
selected after the set SS1 delay time (p9852, p9652) has elapsed. When all the grouped
drives have reached the "Safe Torque Off active" status, this is signaled back via terminal
X122.10 (DO 10: STO group active).
ensure that it is plausible.
Safety Integrated basic functions
9.10 Application examples
401