The **WSBS-15BA-R/Q** is a high-performance, automotive-grade current sense resistor manufactured by Vishay Dale. It is specifically designed as a battery sensor shunt, commonly used in battery management systems (BMS). --- ### 1. General Specifications This component is part of the Power Metal Strip® series, known for its ability to handle high currents with high precision. | Feature | Specification | | :--- | :--- | | **Resistance Value** | Typical range of 100 μΩ to 500 μΩ (variable by specific sub-code) | | **Power Rating** | Up to 36 W | | **Tolerance** | ± 1% or ± 5% | | **Construction** | Solid metal manganese-copper alloy resistive element | | **Mounting Type** | Bolt-on (Terminal structure for busbars) | --- ### 2. Key Electronic Features #### A. Low Resistance Value The device offers extremely low resistance (measured in micro-ohms). This is critical for high-current applications because it minimizes **$I^2R$ power loss** (heat generation) while allowing for accurate voltage drop measurements across the shunt. #### B. Low TCR (Temperature Coefficient of Resistance) * **Performance:** It maintains a low TCR (typically < 20 ppm/°C for the element). * **Benefit:** As the battery current heats the resistor, the resistance remains stable. This ensures that the current readings remain accurate across a wide range of operating temperatures. #### C. High Power Handling The "BA" construction allows the part to dissipate significant heat. Because it is often bolted directly to a battery terminal or a busbar, the metal-to-metal contact acts as a secondary heat sink. #### D. Low Thermal EMF The interface between the resistive alloy and the copper terminals is designed to produce low thermal EMF (Electromotive Force). This prevents "ghost" voltage readings caused by temperature gradients, which would otherwise lead to errors in calculating battery state-of-charge (SoC). --- ### 3. Physical Structure & Integration The **-R/Q** suffix usually refers to specific terminal configurations or packaging styles: * **Construction:** Electron-beam welded copper terminals to a solid metal alloy. * **Connectivity:** Features holes for bolt-on mounting, ensuring a vibration-resistant connection required in automotive environments. * **AEC-Q200 Qualified:** This part is tested to meet the rigorous stress-test requirements of the automotive industry. --- ### 4. Typical Applications 1. **Battery Management Systems (BMS):** Monitoring the charge/discharge cycles of Lead-acid or Lithium-ion batteries. 2. **Electric Vehicles (EV):** Measuring high-current draws for propulsion motors. 3. **Industrial Inverters:** Monitoring power flow in large-scale energy storage systems.