The **DM2N-R** is a specific type of **Magnetic Proximity Sensor** (often referred to as a Door or Reed Switch) commonly used in industrial automation, security systems, and limit detection. It operates on the principle of magnetism to open or close an electrical circuit without physical contact. --- ## 1. Core Technical Specifications The following table outlines the typical electrical characteristics of the DM2N-R series: | Parameter | Specification | | :--- | :--- | | **Contact Form** | Normally Open (NO) / SPST | | **Switching Voltage (Max)** | 100V DC / 125V AC | | **Switching Current (Max)** | 0.5A | | **Contact Rating** | 10W / 10VA | | **Operating Distance** | 15mm to 25mm (Typical) | | **Housing Material** | ABS Plastic / Resin | | **Connection Type** | Wired (Pigtail) | --- ## 2. Key Electronic Components The "Electronic" side of the DM2N-R is relatively simple but highly reliable due to its passive nature. ### A. The Reed Switch (Internal) The heart of the DM2N-R is a **hermetically sealed glass envelope** containing two ferromagnetic metal reeds. * **Mechanism:** When a magnetic field (from a matching magnet) comes close, the reeds become polarized and pull together, completing the circuit. * **Protection:** Because the contacts are sealed in inert gas, they are protected against oxidation, dust, and moisture. ### B. The Magnetic Actuator While not "electronic" in the sense of having a PCB, the actuator is a permanent magnet (usually Neodymium or Alnico) encased in a matching housing. The DM2N-R is designed so that the switch only triggers when the specific magnetic flux density of the actuator is within range. ### C. Wiring Configuration The DM2N-R typically uses a **2-wire configuration**: * **Input/Output:** It acts as a dry contact. It does not require power to operate (Passive); it simply allows current to pass through when the magnet is present. --- ## 3. Operating Logic The "R" in the model often denotes its behavior or physical orientation (Right-angle or Reed-type). | State | Magnet Position | Circuit Status | LED (if equipped) | | :--- | :--- | :--- | :--- | | **Idle** | Magnet Far Away | **Open** (No continuity) | OFF | | **Triggered** | Magnet Close (<20mm) | **Closed** (Continuity) | ON | --- ## 4. Typical Applications * **Pneumatic Cylinders:** Detecting the end-of-stroke position. * **Security:** Monitoring if a door or access panel is closed. * **Safety Interlocks:** Ensuring a machine guard is in place before the system starts. ---