Siemens 3TK28 - Description of the individual safety relays; Introduction to Safety Relays

3TK28 safety relays
Manual, 07/2016, NEB926157502000/RS-AB/003
13
Description of the individual safety relays
3
3.1
Introduction
SIRIUS 3TK28 safety relays are mainly used in autonomous safety applications that are not
connected to a safety-related bus system. Here they are used to evaluate sensors and
ensure safety-related shutdown in case of a hazard. They also check and monitor the
sensors, actuators, and the safety-related functions of the safety relay.
Applications
Depending on the version of the device and the external wiring with sensors and actuators,
applications up to Category 4 in accordance with DIN EN 954-1 or SILCL 3 in accordance
with IEC 62061 / PL
e
as specified in DIN EN ISO 13849-1 can be implemented.
In these applications, 3TK28 safety relays perform the following functions:
● Monitoring the safety functions of the sensors
● Monitoring of the sensor lines
● Monitoring of correct functioning of the safety relay
● Monitoring of actuators for standstill
● Safety-related shutdown in case of hazards