Allen-Bradley 871TM-BH4N12-N3 Proximity Sensor

Allen-Bradley 871TM-BH4N12-N3 is a metal-face inductive proximity sensor with a 12 mm diameter stainless-steel tubular body and a rugged metal face designed for non-contact detection of metal targets in industrial automation. This 871TM series sensor operates on a 2-wire AC/DC supply in the 20–250 V range and provides a normally open (NO) output for simple PLC interfacing. The device is unshielded and features a 4 mm nominal sensing distance, making it suitable for tight mounting spaces where reliable metal detection is required. Termination is via Mini QD connectors for quick field connections and easy replacement in control panels or on machines. As part of Rockwell Automation’s inductive sensor family, it is built to withstand typical industrial environments while delivering repeatable switching performance across a broad voltage window. The 4 mm sensing range combined with the compact 12 mm diameter makes this sensor a compact, robust choice for metal-detection tasks in automation workflows, enabling straightforward integration into control logic that responds to metal presence within the sensor’s range.