Siemens SIRIUS 3RW52 - EMERGENCY STOP Shutdown to SIL 3 or PL E with a 3 SK1 Safety Relay

Example circuits
A.3 Special applications
SIRIUS 3RW52 Soft Starter
Manual, 01/2019, A5E35630451002A/RS-AD/004
183
A.3.3 EMERGENCY STOP shutdown to SIL 3 or PL e with a 3SK1 safety relay
The 3RW52 soft starter has no effect or influence on the safety function of the application.
For this reason, it is neither positively nor negatively considered in the safety application, and
also does not have to be included in the calculation for proof according to the standards.
Safe shutdown up to SILCL 3 according to IEC 62061:2005 / PL e according to
EN ISO 13849-1:2015 requires the use of 2 redundant contactors and monitoring of the
auxiliary contacts of both contactors. Two-channel monitoring of the EMERGENCY STOP is
also required here.
Basic configuration
①
Emergency stop
②
3RT20 contactors
③
3RW52 soft starter
④
Motor
⑤
3SK1 safety relay
Requirements
● If the soft stop function is set (ramp-down time setting element set to > 0 s) and the
emergency stop circuit is tripped, a "Missing load voltage, phase failure / missing load"
fault may be indicated on the soft starter. In this case, the soft starter must be reset
according to the selected RESET MODE.