SIRIUS Safety Switch Device Basic Unit Advanced Series with time delay of 5-300 s. Relay release circuits: 2 S unlatched, 2 S delayed. Us = 24 V DC, screw connection. SIRIUS 3SK1 safety switch device for stand-alone safety applications. The Advanced 3SK112 basic units offer universal applications thanks to multifunctionality and flexible expansion options. They form an innovative system landscape that can implement complex safety functions with a variety of sensors and outputs. With device connectors, the number of inputs and safe outputs can be reliably and easily expanded between devices without wiring effort. Drives up to 3 kW can be directly integrated into the 3SK system with the fail-safe motor starters SIRIUS 3SK11 using device connectors. All components have worldwide approvals, making them well-suited for global use and export. The devices are available with relay or semiconductor outputs, either unlatched or delayed, each with various time ranges, and consistently with screw or spring-loaded connections (Push-In). Extensive accessories such as sealing covers, insertion tabs for wall mounting, and coding pins facilitate handling. Input and output expansions as well as a separate power supply can be used via device connectors without additional wiring effort. The safety switch devices 3SK replace the proven series 3TK28. Safety is a SIRIUS business.