The **FST190** typically refers to a high-precision, industrial-grade **Pressure Transducer/Transmitter**. These devices are designed to convert physical pressure into an electrical signal (current or voltage) for use in PLC systems, data loggers, or digital displays. Below is an explanation of the electronic components and technical specifications common to this series. --- ### 1. Key Electronic Components The FST190 is built using several layers of electronic hardware: | Component | Function | | :--- | :--- | | **Piezoresistive Sensor** | The "heart" of the device; a silicon chip that changes resistance when pressure is applied. | | **Signal Conditioning ASIC** | An Integrated Circuit that amplifies the tiny millivolt signals from the sensor and compensates for temperature drift. | | **A/D Converter** | Converts the analog pressure readings into digital data for internal processing. | | **Output Driver** | Standardizes the signal into industry formats like 4-20mA or 0-10V. | | **EMC Protection** | Includes TVS (Transient Voltage Suppressors) to protect against electrical surges and noise. | --- ### 2. Technical Specifications The electronics are characterized by their output types and power requirements: * **Output Signals:** * **Analog:** 4~20mA (Current Loop), 0~5VDC, or 0.5~4.5V (Ratiometric). * **Digital:** RS485 (Modbus RTU) is common in smart versions. * **Excitation Voltage:** Usually operates on **12-36V DC** (standard 24V DC). * **Electrical Connection:** Typically uses a **DIN 43650 (Hirschmann)** connector or a direct waterproof cable outlet (IP65/IP67). --- ### 3. Wiring Configuration Most FST190 units use a 2-wire or 3-wire system. Below is a standard representation of the 2-wire current loop: ```markdown Pin/Color | Function | Description ----------|----------|------------------------- Pin 1/Red | V+ | Power Supply (12-36V DC) Pin 2/Blue| Signal | 4-20mA Output / Ground ``` ### 4. Electronic Features 1. **Temperature Compensation:** The internal electronics calibrate the sensor output across a range (usually -20°C to +85°C) to ensure accuracy regardless of weather. 2. **Reverse Polarity Protection:** Prevents the device from burning out if the positive and negative wires are accidentally swapped. 3. **High Linearity:** The electronic circuit ensures that the relationship between the physical pressure and the electrical output is a straight line, typically with an error of less than 0.5% FS (Full Scale). ---