The **MLS-20-R/E** is a specific model of a **magnetic proximity sensor** (often categorized under magnetic limit switches). These devices are commonly used in industrial automation for non-contact position detection, particularly for pneumatic cylinders or security gate systems. --- ### 1. Technical Specifications Below are the typical electronic characteristics of the MLS-20 series: | Parameter | Specification | | :--- | :--- | | **Switching Logic** | Normally Open (NO) | | **Sensor Type** | Reed Switch / Magnetic | | **Operating Voltage** | 5V – 240V AC/DC | | **Switching Current** | 100mA max | | **Contact Rating** | 10W max | | **Voltage Drop** | 2.5V max | | **Indicator** | Red LED (R/E models usually feature a light) | --- ### 2. Key Electronic Components The device is comprised of three primary electronic sections: 1. **The Reed Switch:** This is the core component. It consists of two flexible, ferromagnetic metal reeds sealed in a glass tube. When a magnetic field (from a magnet on a piston or bracket) approaches, the reeds are pulled together, closing the circuit. 2. **LED Indicator:** The "R" in the model often signifies a visible indicator. A small Red LED is wired in series with a resistor to provide visual feedback when the circuit is closed. 3. **Protection Circuitry:** Some variants include a small Zener diode or a varistor to protect the reed contacts from voltage spikes (back-EMF) when switching inductive loads. --- ### 3. Wiring Configuration The MLS-20-R/E typically uses a **2-wire** system. Because it is a non-polarized reed switch, it acts as a simple mechanical bridge, though the LED may require specific polarity to light up. ```markdown [Power Source (+)] ---- [Load (PLC/Relay)] ---- (Brown Wire) [ MLS-20 ] (Blue Wire) ---- [Power Source (-)] ``` * **Brown Wire:** Connect to the positive side or the load. * **Blue Wire:** Connect to the negative side or the common. --- ### 4. Applications and Mounting * **Pneumatic Cylinders:** Mounted on the exterior slot of a cylinder to detect when the piston has reached the end of its stroke. * **Security:** Used as a heavy-duty door or gate contact. * **Non-Contact Sensing:** Ideal for environments with dust or liquids, as the electronic parts are fully encapsulated in a resin-filled plastic housing. ---