The **FCR-H3-R** is a specialized high-power, high-precision shunt resistor primarily used for current sensing. It is part of a family of components designed to handle high current loads while maintaining extreme stability and accuracy. --- ### 1. Core Technical Specifications Below are the typical electronic characteristics associated with the FCR-H3-R series: | Feature | Specification | | :--- | :--- | | **Component Type** | Shunt Resistor (Current Sense) | | **Resistance Range** | Typically low milliohm (mΩ) values | | **Power Rating** | High (often ranging from 3W up to 10W depending on heatsinking) | | **Tolerance** | ±0.1% to ±1% (High Precision) | | **Temperature Coefficient (TCR)** | Low (±20ppm/°C to ±50ppm/°C) | | **Mounting Style** | Surface Mount (SMD) / Busbar compatible | --- ### 2. Key Electronic Features #### A. Low Resistance Values The "R" in the suffix usually denotes a sub-ohm resistance value. Because these parts are used to measure current ($I = V/R$), the resistance is kept very low to minimize power dissipation ($P = I^2R$) and prevent voltage drops in the main circuit. #### B. Kelvin Connection (4-Terminal) High-precision shunt resistors like this often utilize a **Kelvin (4-wire) configuration**. * **Two terminals** carry the high main current. * **Two terminals** are used for voltage sensing. This eliminates the resistance of the leads/solder joints from the measurement, ensuring the sensor only reads the voltage drop across the resistive element itself. #### C. Thermal Stability The FCR-H3-R is constructed using specialized alloys (such as Manganin or NiCr). These materials ensure that the resistance value does not drift significantly as the part heats up during high-current operation. --- ### 3. Common Applications Due to its robust power handling, the FCR-H3-R is found in the following electronic systems: * **Battery Management Systems (BMS):** Monitoring charge and discharge cycles in Electric Vehicles (EVs). * **Power Inverters:** Measuring output current for motor control. * **Industrial Power Supplies:** Overcurrent protection and feedback loops. * **DC-DC Converters:** High-efficiency current regulation. --- ### 4. Implementation Example (Simplified) To use this part in a microcontroller-based system, it is typically paired with an **Instrumentation Amplifier** or a dedicated **Current Sense IC**: ```cpp // Pseudocode for calculating current using FCR-H3-R float shuntResistance = 0.001; // 1 mOhm float vDrop = readADC(); // Voltage measured across Kelvin terminals // Ohm's Law: I = V / R float currentAmps = vDrop / shuntResistance; ```