Overview
The Allen-Bradley 871L-D20EP40-T3 is a premium limit-style inductive proximity sensor engineered for industrial automation systems requiring precise object detection. Built to Allen-Bradley’s quality standards, this 40 mm barrel-style sensor delivers consistent performance across a broad range of manufacturing, material handling, and process control applications. The compact form factor and shielded design make it ideal for environments with electrical noise and space constraints.
Key Features
- 20 mm Sensing Distance: Provides reliable detection at a fixed 20 mm range, suitable for part positioning and limit switch applications.
- 3-Wire DC Design: Simple integration with 24 VDC control systems; 400 mA maximum load current supports typical solenoid and relay coils.
- Selectable Output: Configurable N.O. (normally open) or N.C. (normally closed) switching logic for flexible circuit design.
- Shielded Housing: Quasi-flat mounting with plastic construction resists electromagnetic interference, extending sensor lifespan in harsh industrial environments.
- .5″ NPT Conduit Connection: Standard threaded entry simplifies panel mounting and cable entry in control cabinets.
- CE & KC Certified: Meets international safety and performance standards for European and Korean markets.
Technical Specifications
- Sensing Distance: 20 mm (fixed)
- Head Size: 40 mm diameter barrel
- Connection Type: 3-wire DC, .5″ NPT conduit threads
- Output Type: PNP (source), selectable N.O./N.C.
- Maximum Load Current: 400 mA
- Operating Frequency: 150 Hz
- Mounting Style: Quasi-flat
- Material: Plastic housing
- Output Configuration: Change-over (1 NOC & 1 NCC available)
- Standards: CE, KC
- Country of Origin: Germany (DE)
Typical Applications
The 871L-D20EP40-T3 excels in part detection, position verification, and limit switching across discrete manufacturing. Common uses include conveyor line material detection, pneumatic/hydraulic actuator end-of-stroke confirmation, packaging machine part presence sensing, and CNC machine tool position monitoring. Its 150 Hz response speed supports high-cycle-rate automated systems, and the shielded design performs reliably around motor drives and VFDs.
Compatibility & Replacements
The 871L-D20EP40-T3 is a genuine Allen-Bradley inductive sensor compatible with any 24 VDC logic controller (PLC/PAC) and relay-based control circuits using standard 3-wire DC sensor wiring. When planning replacements or system expansions, verify sensing distance (20 mm fixed) and output polarity (PNP source vs. NPN sink) against your application. Similar proximity sensors in the 871L series (such as models with 30 mm or 40 mm sensing distances) can substitute if wiring configuration and voltage match. Always consult the detailed datasheet before substituting alternative brands to ensure mounting footprint, response time, and hysteresis compatibility.
