Relays for emergency shut-down systems
Weidmuller’s Safeseries SIL relays now feature cULus approvals and include single- and dual-channel DIN-rail mounted modules suitable for switching safety related circuits up to SIL3 level as per IEC61508. Applications include tank overfill protection and shutdown controls for refineries and oil and gas storage facilities. The relays accept 24Vdc safety inputs and offer a monitoring circuit option with wide-range input voltages from 24 to 230 V ac/dc. The single-channel models operate in the de-energize-to-safe mode. The optional gas corrosion-resistant G3 coating for the circuit board makes them suitable for use in the harsh environmental conditions of refineries and tank farms.
A two-channel model features a test input, and is designed for use in either energize-to-safe or de-energize-to-safe mode. This versatile relay is suitable for on/off actuator safety switching. A second two-channel module, designed specifically for safely shutting down the fuel supply to a combustion burner, features a SIL3 fuel cut-off relay that interfaces with the burner management system of a boiler’s furnace combustion controls. The Safeseries SIL relay modules are all 22 mm wide and DIN-rail mountable. The housings feature pluggable field connectors to simplify removal, front status indication and in most models, an externally accessible fuse. The ambient temperature range is -25 C to +50 C for all models.
– Edited by CFE Media. See more Control Engineering energy and power products.