The **WSBS-22B-R** is a high-precision, industrial-grade current sense resistor manufactured by Vishay Dale. It is specifically designed as a battery shunt for high-current applications. --- ## 1. Technical Specifications The WSBS-22B-R belongs to the Power Metal Strip® family. Below are its primary electrical characteristics: | Parameter | Value / Range | | :--- | :--- | | **Resistance Value** | 100 $\mu\Omega$ (0.0001 $\Omega$) to 500 $\mu\Omega$ | | **Power Rating** | 36 W (Continuous) | | **Tolerance** | $\pm 5.0\%$ (Standard) | | **Temperature Coefficient (TCR)** | $< 20 \text{ ppm/}^\circ\text{C}$ | | **Operating Temp Range** | $-65^\circ\text{C}$ to $+170^\circ\text{C}$ | | **Inductance** | $< 5 \text{ nH}$ | --- ## 2. Key Electronic Features ### A. Low Resistance (Shunt) Because the resistance is extremely low (measured in micro-ohms), the voltage drop across the component is minimal. This allows for high-current measurement without significant energy loss or heat generation. ### B. Manganin Resistance Element The core resistive material is a solid metal **Manganin** alloy. Manganin is chosen for its: * Excellent long-term stability. * Extremely low Thermal EMF (Electromotive Force) when bonded to copper, which prevents measurement errors caused by temperature gradients. ### C. All-Welded Construction The part features an all-welded construction between the Manganin element and the copper terminals. This ensures superior mechanical strength and low contact resistance, which is critical for accuracy in high-amperage circuits. --- ## 3. Physical Layout and Connection The WSBS-22B-R is designed for heavy-duty mounting: * **Terminals:** Large copper terminals for heat dissipation. * **Mounting:** Typically features two bolt holes for secure attachment to busbars or heavy-gauge battery cables. * **Voltage Sensing:** Often used in a 4-terminal (Kelvin) configuration where the current flows through the main bolts, and sensing wires are attached to measure the precise voltage drop across the Manganin element. --- ## 4. Common Applications Due to its high power handling and precision, it is frequently used in: 1. **Electric Vehicles (EV):** Battery Management Systems (BMS) to monitor state-of-charge. 2. **Solar Inverters:** Monitoring current flow from large battery banks. 3. **Industrial UPS:** Large-scale uninterruptible power supplies. 4. **Forklifts/Heavy Machinery:** DC motor control and battery monitoring. --- ## 5. Part Number Breakdown (Example) `WSBS` - `22B` - `R` - `0001` - `J` - `K` * **WSBS:** Model Series (Welded Shunt Battery Sensor). * **22B:** Size/Style code. * **R:** Denotes the version (Standard/Revised). * **0001:** Resistance value (e.g., $100 \mu\Omega$).