The **M2SES-2BC-R2** is a specialized electronic component, typically identified as a **high-precision, spring-loaded probe pin** (also known as a Pogo Pin) used primarily in automated testing equipment (ATE) and PCB testing fixtures. Below is a detailed breakdown of its electronic and mechanical specifications. --- ### 1. Technical Specifications The performance of a probe pin is defined by its electrical conductivity and its mechanical durability. | Feature | Specification | | :--- | :--- | | **Full Stroke** | Approximately 4.0 mm - 5.5 mm (depending on series) | | **Rated Current** | 3A - 5A (Standard for this gauge) | | **Contact Resistance** | < 50 mΩ | | **Spring Force** | ~150g - 250g at working stroke | | **Plating** | Gold-plated over Nickel (for high conductivity) | | **Body Material** | Phosphor Bronze or Brass | --- ### 2. Key Electronic Components & Materials To understand the "parts" of the M2SES-2BC-R2, we must look at its internal assembly: #### A. The Plunger (Head) * **Role:** The moving part that makes direct contact with the test point (pad, lead, or via). * **Tip Style:** The "BC" in the part number often refers to a **Crown** or **Concave** tip style, designed to center itself on pins or solder bumps. * **Material:** Usually heat-treated Beryllium Copper (BeCu) for hardness and gold-plated to prevent oxidation. #### B. The Barrel (Body) * **Role:** Houses the spring and provides the conductive path from the plunger to the receptacle. * **Material:** Phosphor Bronze or Brass with gold plating on the inside and outside to ensure low electrical resistance. #### C. The Internal Spring * **Role:** Provides the mechanical pressure (preload) necessary to break through surface oxides on the PCB being tested. * **Material:** Music wire or Stainless Steel. Gold plating is often applied to prevent corrosion and improve internal current flow. --- ### 3. Application Use Cases The M2SES series is widely used in "Bed of Nails" testing environments: 1. **ICT (In-Circuit Testing):** Checking for shorts, opens, and component values on a populated PCB. 2. **FCT (Functional Testing):** Powering up the device and simulating signals. 3. **Programming:** Temporary connection to flash firmware onto microcontrollers during production. --- ### 4. Part Number Breakdown (Typical) While manufacturers vary slightly, the nomenclature generally follows this logic: * **M2:** Series/Diameter Size. * **SES:** Spring type or Mounting style. * **2BC:** Head/Tip style (Crown/Pointed). * **R2:** Specific revision or gold-plating thickness.