SIL-Rated Relays Operate With Fail-Safe Controls
Phoenix Contact has expanded its range of safety process relays. The PSR-FSP2/2x1 and PSR–FSP/2x1 process safety relays are safe interposing relays that were designed to operate with fail-safe controls in process applications.
The PSR-FSP/2x1 can be used in applications up to a Safety Integrity Level (SIL) 3, and the PSR-FSP2/2x1 can be used for up to a SIL 2 requirement, according to IEC 61508.
The new additions have two normally open safe outputs. The outputs for the PSR-FSP/2x1 are internally redundant, and the outputs for the PSR-FSP2/2x1 are not. Both have a normally closed status contact that can be wired to a SIL-rated controller to perform an automated "proof test." This can ensure that the targeted SIL level is maintained.
These process safety relays are compatible with "test pulses" and inrush constraints that occur on safe PLC/DCS outputs. The relays measure 17.5-mm wide.