Differences between Pressure Transducers and Pressure Transmitters

Brian Craig

April 06, 2021

Pressure transmitters and pressure transducers, both act as advanced pressure gauges. Although the purpose of utilizing both these pressure gauges is nearly the same, the devices possess different technical specifications. Often the manufacturers and users of pressure transmitters and pressure transducers consider these devices interchangeable. However, they are not really interchangeable. They can be used for pressure level measurement but the performance characteristics of these two pressure gauges vary in various aspects. When it comes to the selection of a transmitter or a transducer, these devices are often pitted against each other due to incomplete knowledge about their functioning. This post offers an introduction and differentiating characteristics of pressure transmitters and pressure transducers which makes the selection convenient.

Before getting to the differential characteristics of pressure transmitters and pressure transducers, let us introduce both pressure gauges individually.

Pressure Transducer

The pressure transducer is a piezo-resistive or thin-film pressure sensor. This device features a pressure sensor and a device body that is interconnected with an electric circuit. The physical pressure variation sensed by the pressure sensor is translated to an electronic value that can be processed for calculations. The pressure transducer only converts a physical pressure measurement into an electronically readable value. The standardization or compensation of pressure measurement is not done by the transducer.

Pressure Transmitter

The pressure transmitters are upgraded sub-set of the transducers. These devices linearize, amplify, and compensate the pressure measurements before displaying the reading. Transmitters offer smart measurement of pressure, therefore, pressure monitoring and control activities can be performed using a pressure transmitter.

Now that both the pressure gauges are introduced, let us discuss a few differentiating characteristics of both devices.

Differences between Pressure Transducers and Pressure Transmitters

Although designed for the same purpose, the performance characteristics of these devices differ in the following aspects.

Pressure transducers ideally translate the physical pressure variables into the analog signals. On the other hand, the transmitter can translate the physical pressure variable into voltage signals, milliamp signals, or digital signals.
The transducers do not standardize or compensate the pressure value displayed as reading. The transmitter on the other hand linearizes, amplifies, modifies, and digitalizes the pressure value based on the type of output demanded by the user.
The output signal of the transducer is proportional to supply, therefore, it gives a ratiometric output. Commonly, transducer output is in the form of mV. The transmitter output can be in the form of voltage, current, frequency, or digitalized reading.
Transducers measure the pressure at live zero conditions. Whereas, the transmitter can be calibrated and tested for zero span adjustment.
The transducers require integration with Supervisory Control and Data Acquisition (SCADA) control system for telemetric or remote monitoring and control operations. However, the electronic circuitry of the pressure transmitters can be calibrated by using HART protocol. These transmitters are called smart transmitters.

Considering the above-mentioned differentiating factors of pressure transmitters and pressure transducers, the choice between both of the pressure gauges can be made. Along with the operational requirements, the quality of equipment must be considered during purchase. For that, you should source the pressure transmitters or transducers from the trusted manufacturers or suppliers like The Transmitter Shop (TTS). The company offers a wide range of transmitters and transducers from high-end brands like Fisher, Rosemount, Foxboro, Honeywell, etc.