The **BAS-M-R0002** is a specialized precision current sensing resistor (often referred to as a Shunt Resistor) manufactured by **Isabellenhütte**. It is part of the BAS series, designed for high-current applications where stability and low resistance are critical. ### 1. Technical Specifications The following table summarizes the key electronic characteristics of the BAS-M-R0002: | Parameter | Value | | :--- | :--- | | **Resistance Value** | 0.2 mΩ (0.0002 Ω) | | **Tolerance** | ±1% (Standard) / ±5% | | **Power Rating** | Up to 36W (Depending on cooling/mounting) | | **Temperature Coefficient (TCR)** | < 50 ppm/K (between 20°C and 60°C) | | **Operating Temperature Range** | -55°C to +175°C | | **Material** | MANGANIN® (Alloy) | | **Inductance** | < 3 nH | --- ### 2. Core Electronic Components & Construction #### A. Resistive Element (MANGANIN®) The heart of the BAS-M-R0002 is the **MANGANIN®** alloy. This is a precision material chosen for its: * **Low TCR:** The resistance does not change significantly as the part heats up. * **Long-term Stability:** It maintains its 0.2 mΩ value over thousands of hours of operation. * **Low Thermal EMF:** Minimizes voltage errors caused by temperature gradients across different metals (Copper vs. Manganin). #### B. Electron-Beam Welded Construction The part is manufactured using **ISA-WELD®** technology. The resistive alloy is electron-beam welded between two heavy copper connectors. * **Copper Terminals:** Provide excellent electrical conductivity and serve as a heat sink to dissipate the thermal energy generated by high currents. * **Large Surface Area:** Designed for heavy-duty busbar mounting or high-current PCB integration. --- ### 3. Key Electronic Functions 1. **Current Sensing (Ohm’s Law):** By measuring the voltage drop ($V$) across the known $0.2 \text{ m}\Omega$ resistance ($R$), a controller can calculate the current ($I$) flowing through the system: $$I = \frac{V}{R}$$ 2. **Overcurrent Protection:** Used in Battery Management Systems (BMS) to detect short circuits or surges instantly. 3. **Energy Monitoring:** Allows for precise calculation of Ampere-hours (Ah) in electric vehicle batteries. --- ### 4. Common Applications * **Automotive:** Battery Management Systems (BMS) in EVs and Hybrids. * **Industrial:** High-current inverters and power converters. * **Energy:** Large-scale battery storage systems and smart grids.