SN04 series 4mm Inductive Proximity Switch (models: SN04N, SN04N2, SN04P, SN04P2, SN04Y1, SN04N) A compact, nocontact sensor family for reliable metal detection and simple integration. These SN04 sensors provide a 4 mm sensing range with an NPN, 3wire, normallyopen (NO) output and operate from 6–30 V DC. Ideal for industrial automation tasks where consistent metalpart sensing and uncomplicated wiring are required. Key benefits — why this sensor solves problems Noncontact detection reduces mechanical wear and maintenance compared with mechanical switches. Simple, threewire NPN output allows straightforward connection to PLCs, controllers, relays, and other sinkinginput devices. Wide supply voltage range (6–30 V DC) supports flexible deployment across common industrial and automation systems. Small sensing distance (4 mm) enables precise detection of small or closely spaced metal targets where accuracy matters. Key attributes and specifications Models: SN04N, SN04N2, SN04P, SN04P2, SN04Y1, SN04N Sensing distance: 4 mm (approach/sensing range) Output type: NPN (sinking) Wiring: 3wire configuration (supply, ground, output) Switching mode: NO (normally open) Supply voltage: 6–30 V DC Sensing principle: Inductive proximity (detects metal objects) Typical applications and use cases Conveyor part counting and presence detection: Detect metallic parts on assembly and conveyor lines without physical contact, improving throughput and reducing downtime. Position sensing in automated machinery: Confirm metal component positions for pickandplace, robotic alignment, or toolchange verification. Limit switching and safety interlocks: mechanical limit switches to provide more durable, longlife sensing in packaging, printing, and material handling equipment. Installation and compatibility notes Intended for detection of metallic targets using inductive sensing; performance depends on target size, orientation, and material. Connect to devices that accept NPN/sinking outputs; wiring uses three conductors for power, ground, and output signal. Maintain recommended sensing distance (4 mm) and avoid mounting directly against large metal masses that may affect detection. Follow standard wiring and grounding practices for stable operation. Applications in context Manufacturing line: Use an SN04N2 to verify metal clips are present before sealing operations, reducing rejected parts. CNC tooling: Fit an SN04P at a toolchange station to confirm the presence of a metal tool holder before machining cycles start. Packaging: Mount an SN04Y1 to detect metal lids or caps during sorting and counting stages to improve quality control. This SN04 family of 4 mm inductive, NPN, 3wire, NO proximity switches provides a straightforward, durable solution for metal detection tasks across automation and industrial equipment.