LJ18A38Z/AX Inductive Proximity Switch Sensor M18 DC 636V 3 NPN Normally Closed Key benefits Reliable metal sensing: Detects metallic targets without contact, reducing wear and maintenance compared with mechanical switches. Wide DC voltage range: Operates across DC 6–36V for compatibility with common industrial control systems. Simple integration: M18 threaded cylindrical housing and 3wire NPN output make mounting and wiring straightforward in existing installations. Safety and logicfriendly output: Normally closed (NC) behavior supports failsafe and safetyoriented wiring or specific control logic that requires a closed circuit when the sensor is not actuated. What it is and how it solves problems The LJ18A38Z/AX is an inductive proximity switch designed to sense nearby metal objects without physical contact. It eliminates mechanical contact points that wear out over time, improves system uptime, and provides repeatable, reliable switching for automation, machinery, and control panels. Its 3wire NPN normally closed configuration allows direct connection to NPN sinking inputs and PLCs that expect NC signals, simplifying wiring for applications that require a closed signal in the idle state. Key attributes Model: LJ18A38Z/AX Sensing type: Inductive (metal detection) Thread/size: M18 cylindrical threaded housing for easy panel or bracket mounting Supply voltage: DC 6–36V Output: 3wire NPN, normally closed (NC) Mounting: Threaded M18 body for secure fastening and position adjustment Practical advantages in the field Easy mounting and alignment using the M18 thread standard; can be fixed with standard nuts or clamps. Broad DC voltage range reduces the need for additional power conversion and suits many 12V, 24V, and 36V control systems. 3wire NPN NC output supports common industrial wiring practices and integrates with PLC inputs and relay logic that require normally closed sensing. Typical applications Conveyor and material handling: Detect metal parts passing a conveyor for counting, sorting, or gating, with durable contactless switching. Position and endoftravel sensing: Monitor machine slides, doors, or actuator strokes where a normally closed signal is preferred for safety monitoring or to detect loss of signal. Industrial automation and assembly: Use for part presence detection, fixture verification, and process control in manufacturing equipment where reliable metal detection is required. Installation notes Mount in an appropriate bracket or panel using the M18 threaded body; adjust distance and secure with nuts for stable detection position. Connect the three wires according to NPN sinking wiring practices and the NC logic required by your controller or PLC. Confirm compatibility with your control system voltage (DC 6–36V) before wiring. The LJ18A38Z/AX is a practical choice when you need reliable, contactless metal detection in a compact M18 package with a wide DC supply range and a 3wire NPN normally closed output for straightforward integration into industrial control circuits.