Allen-Bradley 1734-IB8SK SIL 3 Safety Input Module By wayne No Comments on Allen-Bradley 1734-IB8SK SIL 3 Safety Input Module 3 Min Read Buy the Allen-Bradley 1734-IB8SK POINT Guard I/O module with 8 sinking safety inputs and conformal coating. It supports SIL 3 and Cat. 4 systems. Order now for fast delivery.