What is the difference between pressure sensor, pressure transducer and pressure transmitter?

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What is the difference between pressure sensor, pressure transducer and pressure transmitter? [Copy link]

Pressure sensor, pressure transducer, and pressure transmitterThe terms are often used interchangeably, and the exact definitions may vary depending on the source. Below are general definitions. Pressure sensors typically have a millivolt output signal, transducers have an amplified voltage output, and transmitters provide a 4-20mA output signal. The terms pressure sensor, pressure transducer, and pressure transmitter are interchangeable in some cases in the industrial world. A pressure sensor can be described by a 4-20mA output signal, while a pressure transducer is described using a millivolt signal. Once the relevant details are described to define the output signal and application, the correct term can be determined. Below is a quick guide to each term and its advantages and limitations. Pressure Sensor Pressure sensor is typically a millivolt (mV) output signal (also a general term for all pressure types); a device that measures pressure. The millivolt output signal can usually be used ten to twenty feet away from the electronic device without significant signal loss. The signal is proportional to the power supply. A 5VDC power supply with a 10mV/V output signal produces a 0-50mV output signal. Older technologies such as bonded foil strain gauges or thin film technology produce 2-3mV/V (millivolts/volt) output signals, while MEMS technology can reliably produce 20mV/V output signals. Millivolt output signals give design engineers the flexibility to adjust the output signal to system needs and can reduce package size and cost. Pressure transducers Pressure transducers are typically high-level voltage or frequency output signals, including 0.5 to 4.5V ratiometric (output signal is proportional to the power supply), 1-5V, and 1-6kHz. These output signals should be used within twenty feet of the electronic device. Voltage output signals provide low power consumption for remote battery-powered equipment such as wellhead SCADA systems. Supply voltages are typically 8-28VDC, except for the 0.5-4.5V output, which requires a 5VDC regulated supply. Older voltage output signals, such as 0-5V, do not have the “non-zero minimum output” feature where the signal is present when the sensor is at zero pressure. The risk is that the system cannot distinguish between a sensor failure with no output and zero pressure. Pressure transmitters Pressure transmitters are typically current output signals, i.e. 4-20mA, where the device measures current rather than voltage; most pressure transmitters are two-wire devices. 4-20mA pressure transmitters offer good immunity to electromagnetic interference (EMI/RFI) and require a power supply of 8-28VDC. Because the signal is generating current, more battery life is consumed if operated at full pressure.