SIRIUS safety relay for safety-related speed monitoring, DC 24 V, 45 mm spring-loaded terminal. Unlatched: 2 S FK, delayed: 0 MK: 2 electrically, NAMUR version, auto-start/manual start. Basic unit maximum achievable PL according to EN 13849-1: e, maximum achievable SIL according to IEC 61508: 3. The SIRIUS 3TK28 speed monitor is designed for safe standstill and speed monitoring in machines and systems, such as motors. The device is compatible with all common sensors and features an adjustable release delay. With simple parameterization and continuous diagnostics via the display, troubleshooting can be performed quickly at any time. Thanks to the integrated protective door monitoring, the device ensures higher safety by only allowing the system to be released in a safe state. The devices are available in various voltages and with screw or spring-loaded connections. Accessories such as connection cables, adapters, and labeling plates facilitate handling. Safety is a SIRIUS business.