LJ12A3-4-Z/BX Inductive Proximity Sensor – NPN

LJ12A3-4-Z/BX Inductive Proximity Sensor – NPN is a compact and reliable sensor designed to detect metallic objects without physical contact. With its 4 mm sensing distance, rugged build, and NPN normally-open output, it fits seamlessly into automation systems, CNC machines, and robotics projects where consistent performance is essential.

Key Features:

• Non-Contact Detection: Accurately senses metal targets without wear or mechanical stress.
• 4 mm Sensing Range: Provides reliable detection at close distances for precision applications.
• NPN Normally Open Output: Simplifies integration with controllers, PLCs, and microcontrollers.
• Stable Operation: Performs well even in dusty or oily environments.
• Compact Cylindrical Housing: Easy to mount in tight machine enclosures and automation rigs.
• LED Indicator: Built-in status LED provides clear visual confirmation of detection.

Technical Specifications:

• Model: LJ12A3-4-Z/BX
• Operating Voltage: 6 V DC to 36 V DC
• Sensing Distance: 4 mm (for iron/steel targets)
• Output Type: NPN, Normally Open (NO)
• Max Output Current: 300 mA
• Switching Frequency: Up to 500 Hz
• Operating Temperature: −25 °C to +70 °C

Mechanical Specifications:

• Housing Material: Nickel-plated brass for durability
• Thread Size: M12 × 1 for easy mounting with standard nuts
• Connection: 3-wire, shielded cable (approx. 1 m length)
• Indicator: Red LED shows active sensing status

Dimensions:

• Overall Length: ~55 mm
• Body Diameter: 12 mm (M12 threaded)
• Sensing Face Diameter: 12 mm
• Cable Length: ~1000 mm

Pinout and Wiring:

• Brown Wire: VCC (+6 V to +36 V DC)
• Blue Wire: Ground (0 V)
• Black Wire: Output (NPN, Normally Open)
• Wiring Tip: Connect brown to positive supply, blue to ground, and black to the controller input or relay circuit.

Datasheet Reference:

• Refer to the LJ12A3-4-Z/BX datasheet for detailed electrical characteristics, wiring diagrams, and recommended usage guidelines.

Applications:

• 3D Printers: Used as an auto-bed leveling probe for consistent printing surfaces.
• CNC Machines: Detects metal parts and tool positions for automation accuracy.
• Industrial Automation: Suitable for object counting, conveyor systems, and machine positioning.
• Robotics: Enables non-contact position sensing in robotic arms and assembly lines.

Equivalent Models:

• LJ12A3-4-Z/AX: Similar version with PNP output
• LJ18A3-8-Z/BX: Larger M18 body with 8 mm sensing range
• TL-Q5MC1: Omron equivalent inductive proximity sensor

Package Includes:

• 1 x LJ12A3-4-Z/BX Inductive Proximity Sensor – NPN
• 2 x Mounting Nuts (M12)