SIRIUS safety relay output extension 4RO with relay enabling circuits 4 NO contacts plus relay signaling circuit 1 NC contact Us = 24 V DC spring-loaded connection (push-in) output extension SIRIUS 3SK1 for safety relays.The 3SK output extensions are used to supplement a basic device with additional safe outputs with a switching capacity of up to 10 A. They can be connected to any 3SK basic device by wiring. All devices with a control supply voltage of 24 V DC can also be connected to the Advanced 3SK1 and 3SK2 basic devices using the 3ZY12 device connector.The devices have four (AC-15 5 A) or three (AC-15 10 A) safe outputs. You can choose between a control voltage of 24 V or a wide voltage. Available with screw or spring-loaded connection (push-in). The 3SK safety relays replace the proven 3TK28 series. Safety is a SIRIUS business.