The **S2-B6-R** is a specific model within the **S2 series** of subminiature, high-performance optical sensors, typically manufactured by companies like **Datasensor (Datalogic)**. These devices are used in industrial automation for object detection. --- ### 1. Technical Specifications The "B6-R" suffix defines the specific functionality and output type of this electronic part. | Feature | Specification | | :--- | :--- | | **Sensor Type** | Polarized Retroreflective | | **Operating Voltage** | 10 - 30 VDC | | **Output Type** | PNP (Logic High when triggered) | | **Switching Mode** | Dark ON (Output active when light is blocked) | | **Connection** | 2-meter Cable (4-wire) | | **Operating Distance** | 0.1 to 3 meters (with reflector) | | **Response Time** | 1 ms | --- ### 2. Electronic Internal Components The internal circuitry of the S2-B6-R consists of several critical stages: #### A. The Emitter Stage * **LED Source:** Typically uses a visible Red LED (660 nm). * **Polarizing Filter:** Aligns light waves in a single plane. This allows the sensor to distinguish between the reflection from a prismatic reflector and the reflection from a shiny object (like a soda can). #### B. The Receiver Stage * **Photodiode:** A high-speed semiconductor that converts incoming photons into an electrical current. * **Internal Comparator:** An IC that compares the received signal against a threshold to decide if an object is present. #### C. Output Circuitry * **Transistor Switch:** A PNP bipolar junction transistor (BJT) that acts as an electronic switch. * **Protection Circuitry:** Includes Reverse Polarity protection (prevents damage if wired incorrectly) and Short-Circuit protection. --- ### 3. Wiring Diagram (4-Wire Configuration) The S2-B6-R utilizes a standard industrial color code for its electrical connections: ```markdown Brown (+) ----> 10-30 VDC Blue (-) ----> 0V (GND) Black (OUT) --> Load / PLC Input (PNP) White (NC) ---> Usually Not Connected or used for specific configurations ``` --- ### 4. Application Logic Because this is a **Polarized Retroreflective** sensor: 1. **Idle State:** The sensor emits light; the reflector bounces it back; the receiver sees the light. 2. **Detection State:** An object breaks the beam. The receiver stops seeing the reflected light. 3. **B6-R Logic:** Since it is **Dark ON**, the PNP output (Black wire) becomes **Active** when the beam is broken (dark).