Siemens SIRIUS 3RK3 - Overview; 3 RK3 Modular Safety System

Overview
3
3.1 3RK3 Modular Safety System
Safety systems
Safety systems are part of machines and plants. Their task is to minimize possible hazards for
humans, machines and the environment. To this end, they monitor safety functions such as
Emergency Stop and switch o󹪜 the plant or system in a safety-related fashion. A safety system
consists of sensors for sensing signals of the protective equipment (e.g. protective doors), from
safety relays (e.g. MSS 3RK3) that evaluate these signals and from actuators (e.g. 3RM1 Failsafe
motor starters; 3RT contactors) that are controlled by the safety system and respond accordingly.
In most countries in the world there are binding regulations on the safeguarding of machines
and plants. For Europe, the European Machinery Directive (2006/42/EC) de󹪝nes the basic
requirements for machine safety. The technical details of these requirements are speci󹪝ed in
"harmonized" standards such as EN 62061 or EN ISO 13849-1 with the highest classi󹪝cation
SILCL 3 or PL e/Cat. 4 for production automation.
3RK3 Modular Safety System
The 3RK3 Modular Safety System is a software-parameterizable safety relay that can be used to
interconnect several safety applications. In this way, you can set shutdown ranges, for example,
and freely de󹪝ne other dependencies. The MSS 3RK3 is basically suitable for applications
involving two or more safety-related functions.
The MSS 3RK3 reads sensor signals via inputs, combines these signals in software-
parameterizable logic, and uses the processed signals to set and reset the outputs to control
actuators in a safety-related manner.
Depending on the version of the device and the external connection of sensors and actuators,
applications can be implemented at up to SIL 3 in accordance with EN 61508 and PL e/Cat. 4 in
accordance with EN ISO 13849-1.
At least one of the following 3RK3 central units and the Safety ES parameterization and
diagnostics software are required for every system con󹪝guration.
• MSS 3RK3 Basic
• MSS 3RK3 Advanced
• MSS 3RK3 ASIsafe basic
• MSS 3RK3 ASIsafe extended
SIRIUS 3RK3 Modular Safety System
Equipment Manual, 07/2020, NEB926253002000/RS-AC/006 33