The Siemens Range SIRIUS safety relay Output expansion 4RO with relay enabling circuits 4 NO contacts plus Relay signalling circuit 1 NC contact Us = 110-240 V AC/DC Spring-type terminal (push-in) Output expansion SIRIUS 3SK1 for safety relays.
The 3SK output expansions are used for supplementing basic units with additional safe outputs with a switching capacity of up to 10Â A. They can be connected to each 3SK basic unit by wiring. All devices with a 24Â VÂ DC control supply voltage can also be connected to the 3SK1 and 3SK2 Advanced basic units using 3ZY12 device connectors.
The devices have four (AC-15 5 A) or three (AC-15 10 A) fail-safe outputs. There is a choice between a control supply voltage of 24 V or a wide voltage range. Available with screw or spring-type terminals (push-in) across the board.
The 3SK safety relays are replacing the proven 3TK28 series.
Safety is a SIRIUS business.

2 electrical Auto-start/manual start Basic device
Protection class IP of the enclosure IP20