Instrument technicians should be familiar with pressure sensors, pressure transducers, and pressure transmitters

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Terms such as pressure sensor, pressure transducer, and pressure transmitter are often used interchangeably, and their precise definitions may vary depending on the source. The following is a general definition. Pressure sensors typically produce millivolt-level output signals; transducers offer amplified voltage outputs, whereas transmitters provide 4-20mA output signals. What is the difference between pressure sensors, pressure transducers, and pressure transmitters? yunrun.com.cn/tech/1415.html In certain situations in the industrial field, these terms – pressure sensors, pressure transducers, and pressure transmitters – can be used interchangeably. Pressure sensors can be described by a 4-20mA output signal, whereas pressure transducers use millivolt-level signals. Once the relevant details are described to define the output signal and the application, the correct terminology can be determined. Below is a quick guide introducing each term along with its advantages and limitations. http://yunrun.com.cn/upload/201706/11/201706110238277010.png Pressure sensors typically output signals in millivolts (mV); this is also the universal term for all types of pressure sensors ； Device for measuring pressure. The millivolt output signal can usually be used at a distance of ten to twenty feet from electronic devices without significant signal loss. The signal is proportional to the power supply. A 5VDC power supply with a 10mV/V output signal can generate an output signal ranging from 0-50mV. Traditional technologies such as bonded foil strain gauge or thin-film technology can generate output signals of 2–3 mV/V, while MEMS technology can reliably produce output signals of 20 mV/V. The millivolt-level output signal enables design engineers to adjust the output signal flexibly according to system requirements, while also reducing the package size and costs. Pressure transducers typically output signals at high voltage levels or frequencies, including ratios of 0.5 to 4.5 V (where the output signal is proportional to the power supply voltage), as well as 1–5 V and 1–6 kHz. These output signals should be used within 20 feet of electronic devices. The voltage output signal can provide low power consumption for remote battery-powered devices such as wellhead SCADA systems. Except for the 0.5–4.5V output that requires a 5VDC regulated power supply, the power supply voltage is typically 8–28VDC. Old voltage output signals such as 0-5V do not have the “non-zero minimum output” feature, which ensures that a signal is present when the sensor is at zero pressure. The risk in this case is that the system cannot distinguish between a sensor failure with no output and zero pressure. Pressure transmitters typically provide a current output signal, namely 4-20mA; the device measures current rather than voltage ； Most pressure transmitters are two-wire devices. The 4-20mA pressure transmitter offers good resistance to electromagnetic interference (EMI/RFI) and requires a power supply of 8-28VDC. Since the signal generates a current, operating under full pressure conditions will consume more of the battery life.