EC: PSR-MXF safety relay

Safety — Machine Safety: Phoenix Contact's new PSR-MXF multifunctional safety relay can connect three dual-channel safety sensors in a compact 22.5-mm design. This is a Control Engineering 2015 Engineers’ Choice award winner.
By Control Engineering October 20, 2014

Phoenix Contact’s new PSR-MXF multifunctional safety relay can connect three dual-channel safety sensors in a compact 22.5-mm design. This enables the highest levels of functional safety for a machine or system in a cost-effective, space-saving design. The PSR-MXF does not require any programming or turnstile selection, and can be easily wired with available push-in terminals.

Phoenix Contact PSR-MXF safety relayThe PSR-MXF has three relay sensor circuits: an overriding high-level circuit (typically for an emergency shutdown button) and two independent local sensor circuits. Each local sensor circuit can be activated independently of the other, with each circuit utilizing separate reset functionality. This two-level circuit design is ideal for small machines, which require operator access and an overriding shutdown. Previously, the only method in which a connection like this could be made at the highest levels of safety would be through utilizing multiple safety relays or a configurable safety relay. Using the PSR-MXF over either of these solutions lowers the cost and complexity of the safety system.

The two-tier circuit design also allows for more complex designs for multiple overriding e-stop systems. The PSR-MXF can be wired in series using one of two independent local circuits as a signaling chain. Wiring in this manor will permit all devices in the series (upstream and downstream) to shut down local contacts when any of the overriding e-stops are activated. Previously, this would only have been possible through an expensive distributed logic/fail-safe PLC or utilizing long wire runs back to a central configurable relay. The PSR-MXF module allows for safety system flexibility without the need for software or configuration.

Phoenix Contact, www.phoenixcontact.com