Generic LJ12A3-4-Z/BX Inductive Proximity Sensor NPN NO 4mm DC6–36V - M12 Thread

Connect the brown wire to your positive DC supply voltage (6-36V), the blue wire to the DC common ground, and the black wire is the switched NPN output. When a metal target is detected within 4mm, the black output wire will switch to ground (sink current), completing the circuit to your PLC input or microcontroller pin through a pull-up resistor.

Yes, inductive sensors can detect all conductive metals, but the sensing distance is reduced for non-ferrous metals. For the LJ12A3-4-Z/BX, the 4mm rating is typically for mild steel. For aluminum, expect an effective sensing distance of approximately 1.6-2.4mm. Always test with your specific target material and size for final positioning.

Yes, the 'Z/BX' designation and shielded (flush) design allow for adjacent mounting without mutual interference. You can install multiple sensors closely together on a metal panel. Ensure a minimum gap of one sensor diameter (12mm) between adjacent units for optimal performance.

While a specific Hz rating isn't provided, standard inductive sensors of this type typically achieve switching frequencies up to 1-2 kHz, suitable for high-speed counting applications. The actual maximum frequency depends on the target size, material, and approach speed.