Overview
The Allen-Bradley 42CA-U1JMB-A2 is part of the 42CA family of general-purpose photoelectric sensors. The 42CA 18 mm cylindrical family of general purpose photoelectric sensors is intended for light to medium duty industrial applications. The -U1JMB designation indicates this unit operates in diffuse mode (proximity sensing), detecting the presence or absence of objects at close range without requiring a reflective surface.
Key Features
- 18 mm Cylindrical Enclosure: Industry standard enclosure fits standard mounting locations
- Diffuse Sensing Mode: Detects objects directly in front of sensor for proximity-based applications
- Advanced Electronics: Patented ASIC design offers linear sensitivity adjustment, stability indication and excellent noise immunity
- Status Indication: Two LED indicators provide status of power, output, unstable operation and short-circuit protection
- Stability Warning: The 42CA family provides an indication if the sensor operation is unstable. An indicator flashes if the signal level is too close to the detection threshold. This helps for easy alignment of the sensor and forewarns against detection of a background.
Technical Specifications
- Supply Voltage: 10…30V DC
- Output Current Capacity: up to 100 mA
- Enclosure Size: 18 mm cylindrical plastic
- Sensing Mode: Diffuse (U1)
- Connection: 2 m cable (A2 suffix per Rockwell documentation)
- Operating Principle: Photoelectric diffuse reflection detection
Typical Applications
- Container and product detection on conveyor systems
- Packaging line presence sensing
- Assembly and material handling automation
- Light to medium-duty industrial sensing tasks
- Machine guarding and proximity detection
Compatibility & Replacements
Compatible With
- Allen-Bradley PLCs and controllers (CompactLogix, ControlLogix)
- Any 10-30VDC control system accepting PNP or NPN sensor inputs
- Standard industrial automation wiring configurations
- Discrete I/O modules with 24VDC inputs
Replaces / Drop-In Replacement For
- Verify compatibility with your system integrator before ordering. Other 42CA variants with different sensing modes (retroreflective, polarized) are not direct replacements without reconfiguration.
Works With
- Studio 5000 Logix Designer (via discrete I/O mapping)
- RSLogix 5000 control environments
- Standard 24VDC industrial control wiring
- Any PLC or industrial controller with discrete digital inputs
