Overview
The Allen-Bradley 42CA-D1MPAE-D4 is an 18mm cylindrical diffuse photoelectric sensor from the PHOTOSWITCH product line. With a 100mm (3.9 in.) sensing distance and standard diffuse detection mode, this sensor delivers dependable object detection for light- to medium-duty industrial applications including conveyor monitoring, part presence detection, and packaging systems. The unit features complementary light/dark operate outputs with PNP logic and connects via 4-pin DC Micro (M12) quick-disconnect for quick field replacement.
Key Features
- 100mm standard diffuse range — 0–100 mm adjustable sensing distance with 3 mm minimum sensing distance
- 18mm cylindrical housing — Compact plastic form factor rated IP67 for splash and dust protection
- Dual complementary outputs — Light operate (L.O.) and dark operate (D.O.) outputs for flexible switching logic
- PNP output configuration — Direct compatibility with industrial PLC and relay input modules
- Infrared detection — Manually adjustable sensitivity with patented ASIC linear sensitivity control
- M12 4-pin quick-disconnect connector — Field-replaceable without rewiring; standard 4-pin DC micro cordset (889D-F4AC-2 recommended)
Technical Specifications
- Sensing Distance (adjustable): 0–100 mm (0–3.9 in.)
- Minimum Sensing Distance: 3 mm
- Form Factor: 18mm cylindrical
- Detection Mode: Standard diffuse
- Light Source: Infrared
- Output Type: PNP, DC complementary L.O./D.O.
- Supply Voltage: 10–30 V DC
- Output Current: Up to 100 mA per output
- Response Time: 1.0 ms
- Connector: 4-pin DC Micro (M12) quick-disconnect
- Material: Plastic housing
- IP Rating: IP67 (splash and dust resistant)
- User Interface: Yellow status LED (off = output de-energized)
- Mounting: 18mm M18 thread
Typical Applications
- Conveyor belt presence and motion detection
- Package and carton position sensing in packaging machinery
- Parts counting and bin level monitoring
- Object arrival and departure detection at assembly stations
- Label and tab detection on moving products
- Automatic door and gate activation
- Light- to medium-duty industrial automation systems requiring compact diffuse sensing
Compatibility & Replacements
Compatible With
- Allen-Bradley CompactLogix and ControlLogix PLC I/O modules
- Siemens S7-1200 and S7-1500 digital input cards
- Omron and Mitsubishi PLC input modules (10–30 V DC)
- Standard industrial 24 V DC relay and discrete I/O systems
- Rockwell Automation Studio 5000 (sensor as discrete input)
- PROFINET and EtherCAT I/O gateways (via compatible coupler)
Replaces / Drop-In Replacement For
- Allen-Bradley 42CA-D1MPAE-D4 (original part number — current manufacturer model)
- Previous generation diffuse sensors with equivalent 100mm range and M12 connection
- Generic 18mm diffuse sensors rated 10–30 V DC with PNP output and M12 connector
Works With
- Software: Rockwell Automation Studio 5000, FactoryTalk Design Studio, CODESYS
- Communication: EtherNet/IP, PROFINET (via gateway), Modbus TCP (via PLC logic)
- Cordsets: Recommended 889D-F4AC-2 (4-pin DC Micro M12 quick-disconnect)
- Recommended Reflector: 92-47 (for enhanced surface reflection in diffuse applications)
- Mounting Bracket: Standard M18 threaded sensor mounts




















