LJ12A3 12mm Inductive Proximity Sensor NPN PNP DC 6-36V Switch
LJ12A3 12mm Inductive Proximity Sensor NPN PNP DC 6-36V Switch
LJ12A3 12mm Inductive Proximity Sensor Switch – NPN & PNP, DC 6–36V
The LJ12A3 Inductive Proximity Sensor is a compact, reliable detection switch designed for industrial automation, DIY electronics, CNC machines, 3D printers, and robotics projects. With a 12mm aluminium alloy body, CE certification, and wide 6–36V DC operating voltage, it delivers consistent non-contact object detection in demanding environments. Available in NPN/PNP Normally Open (NO) and Normally Closed (NC) output configurations to suit virtually any control circuit.
Made in Mainland China.
Key Specifications
- Models: LJ12A3-4-ZBX (NPN NO) | LJ12A3-4-ZBY (PNP NO) | LJ12A3-4-ZAX (NPN NC) | LJ12A3-4-ZAY (PNP NC)
- Diameter: 12 mm
- Operating Voltage: DC 6–36V
- Max Output Current: 300 mA
- Output Type: Three-wire NPN / PNP (NO & NC)
- Cable Length: 110 cm (approx. 43 inches)
- Body Material: Aluminium alloy
- Certification: CE
- Warranty: 1 Year
Why Choose This Proximity Sensor?
- ✅ Non-contact detection — no physical wear, longer service life
- ✅ Wide voltage range (6–36V DC) for broad compatibility with PLCs, Arduino, Raspberry Pi, and industrial controllers
- ✅ Dual output options — NPN & PNP configurations for flexible wiring in any circuit
- ✅ Rugged aluminium alloy body — built to withstand vibration, dust, and moisture
- ✅ Generous 110cm lead wire — easy routing inside enclosures and control panels
- ✅ CE certified — meets international safety and electromagnetic compatibility standards
Typical Applications
- 3D printer bed levelling & end-stop sensing
- CNC machine tool positioning
- Conveyor belt object counting & detection
- Robotic arm limit switching
- Automated assembly line metal part detection
- DIY electronics & Arduino/PLC projects
Related Products You May Like
- Air Compressor Pressure Gauge 0-10/0-12/0-25 Bar | DIY Tool
- Electromagnetic Induction Tester – Coil & Circuit Fault Detector
- 360° Bicycle Chain Cleaner Tool | Bike Gear Cleaning Kit
Learn more: OSHA guidance on hand and power tools
Frequently Asked Questions
Q: What is the detection range of the LJ12A3 inductive proximity sensor?
A: The LJ12A3-4-Z series has a standard sensing distance of approximately 4 mm for ferrous (steel/iron) metal targets. Detection distance may vary slightly for non-ferrous metals such as aluminium or copper.
Q: What is the difference between NPN and PNP output on this proximity switch?
A: NPN (sinking) output pulls the signal wire LOW when an object is detected, making it compatible with most PLCs and microcontrollers that use active-low inputs. PNP (sourcing) output pulls the signal wire HIGH when triggered, suitable for active-high input devices. Choose the configuration that matches your controller's input type.
Q: Can I use this inductive proximity sensor with an Arduino or Raspberry Pi?
A: Yes. When powered from a 6V–36V supply, the NPN NO (ZBX) model outputs a low-side signal compatible with Arduino digital input pins (with a pull-up resistor). Ensure your supply voltage and signal level match your microcontroller's logic levels. A 5V or 12V bench supply works well for most hobby applications.
Q: Is this sensor waterproof or suitable for outdoor use?
A: The aluminium alloy housing provides good resistance to dust and light splashing, but the LJ12A3 series is not rated to a specific IP ingress protection standard in the provided specifications. For fully outdoor or high-pressure washdown environments, verify IP rating requirements before installation.