The **FVS-30-R** is an industrial-grade **Flow Velocity Sensor** typically used in cleanroom environments, HVAC systems, and manufacturing processes to monitor air velocity. The "R" suffix usually denotes a specific configuration, such as a remote probe or a specific relay output. --- ## 1. Core Electronic Components The FVS-30-R operates primarily on the principle of **Thermal Anemometry**. Below are the key electronic parts and their functions: | Component | Function | | :--- | :--- | | **RTD Elements** | Resistance Temperature Detectors (usually Platinum) that sense the cooling effect of air. | | **Bridge Circuit** | A Wheatstone bridge used to measure the change in resistance of the RTD. | | **ASIC / Microcontroller** | The "brain" that converts analog resistance changes into a linear digital signal. | | **Output Driver** | Converts internal data into industrial signals (0-5V, 0-10V, or 4-20mA). | | **Potentiometers** | On-board trimmers used for manual zero-point and span calibration. | --- ## 2. Technical Specifications The electronic performance of the FVS-30-R is defined by its power requirements and signal accuracy: ### Electrical Characteristics * **Input Power:** Typically 24V DC (±10%). * **Current Consumption:** Low power consumption, usually < 100mA. * **Output Signal:** Analog output proportional to the air velocity (e.g., 0 to 30 m/s). * **Response Time:** Fast electronic response, often < 1 second. ### Connection Diagram (Typical) Most FVS series sensors use a standard wiring block or an M12 connector: 1. **V+**: Positive Power Supply (Red/Brown) 2. **GND**: Common Ground (Black/Blue) 3. **Vout**: Signal Output (White/Green) --- ## 3. Operating Principle (How it works) The electronics utilize a **Constant Temperature Differential** method: 1. The circuit heats one RTD element to a specific temperature above the ambient air. 2. As air flows over the sensor, it carries heat away (convection). 3. The electronic controller increases the current to keep the temperature constant. 4. The amount of current required is measured and translated into a flow velocity reading. --- ## 4. Maintenance & Safety Features * **Reverse Polarity Protection:** Prevents damage if the power wires are connected backwards. * **Over-current Protection:** Protects the internal circuitry from spikes. * **Dust Resistance:** The electronic probe is often coated to prevent particle accumulation from affecting the thermal reading.