The **FMS-B-R** typically refers to a specific series of **Force Miniature Sensors** (often manufactured by companies like Futek). These are precision strain-gauge-based sensors designed for measuring tension and compression in tight spaces. Below is an explanation of its core electronic components and technical specifications. --- ## 1. Core Electronic Components The FMS-B-R functions through an electromechanical conversion process. The primary internal components include: | Component | Function | | :--- | :--- | | **Metal Foil Strain Gauges** | The primary sensing element. They change electrical resistance when the sensor body deforms under load. | | **Wheatstone Bridge Circuit** | An internal network of four resistors (gauges) that converts small resistance changes into a measurable millivolt (mV) output. | | **Temperature Compensation** | Internal resistors added to the circuit to ensure the sensor remains accurate despite thermal expansion or contraction. | | **Flexure/Spring Element** | The structural metal part (usually Stainless Steel) that deflects slightly to transfer force to the strain gauges. | --- ## 2. Technical Specifications (Electronic) Most FMS-B-R models follow a standard industrial electronic profile: ### A. Electrical Signal * **Rated Output:** Usually **2 mV/V** (nominal). This means for every 1 Volt of excitation, the sensor outputs 2 millivolts at full capacity. * **Excitation Voltage:** Recommended **10V DC**, though it can often operate between 1V and 15V. * **Bridge Resistance:** Typically **350 Ohms** (standard industrial impedance). ### B. Connection Wiring The sensor usually utilizes a 4-conductor shielded cable. The standard color coding is: 1. **Red:** Excitation (+) 2. **Black:** Excitation (-) 3. **Green:** Signal (+) 4. **White:** Signal (-) --- ## 3. Signal Chain Requirements Because the electronic output of the FMS-B-R is an analog millivolt signal, it cannot be read directly by a standard microcontroller (like an Arduino) without peripheral electronics: 1. **Amplification:** A Load Cell Amplifier (e.g., HX711 or an industrial signal conditioner) is required to boost the mV signal to a 0-5V or 0-10V range. 2. **Analog-to-Digital Conversion (ADC):** High-resolution ADCs (24-bit preferred) are used to maintain the precision of the force measurements. 3. **Filtering:** Low-pass electronic filters are often applied to remove high-frequency noise from the environment. --- ## 4. Summary Table of Electronic Characteristics | Feature | Description | | :--- | :--- | | **Sensor Type** | Bonded Foil Strain Gauge | | **Input Impedance** | 350 ~ 450 $\Omega$ | | **Output Impedance** | 350 $\Omega$ (nominal) | | **Insulation Resistance** | > 5000 M$\Omega$ at 50V DC | | **Non-Linearity** | $\pm$0.5% of Rated Output (typical) |