Phoenix Contact PSRclassic PSR-SPP- 24DC/URM4/4X1/2X2/B Expansion Module Safety Relay, 24V dc, Single Channel, 6 Safety

Multi-application Modular System - PSR Series

The PSR safety relays from Phoenix contacts can be quickly and reliably assembled to form a tailor-made safety solution.
To connect using TBUS correctly you will need one PSR-TBUS per module. For the last additional module use one PSR-TBUS-TP instead, this will close the feedback loop. The interface module is used for the connection of up to four safety sensors with NC/NO contacts to the safety relay PSR-SDC4, with screw connection.