What´s the difference between a pressure transducer and a pressure sensor?

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Pressure transmitter? Pressure transducer? Pressure sensor? Pressure switch? When searching for devices that work with pressure, you will come across many terms that can be confusing to someone new to space. What are they and how are they different from each other?

Pressure Sensors

A Pressure Sensor is the element of a measuring system that is directly affected by a phenomenon, body, or substance carrying a quantity to be measured like pressure in this case. For example: the Bourdon tube of a mechanical pressure gauge. The pressure from the process the Bourdon tube connected to stresses the material, the stress causes the tube to strain and uncoil, changing the position of the hand on a dial indicator.

Pressure transducer

A Transducer is a device, used in measurement, that provides an output quantity having a specified relation to the input quantity For example: a strain gauge whose resistance value changes proportionally to the strain it experiences and they are commonly used in pressure transducers as the sensing element. When configured as a whetstone bridge, this transduction from strain to resistance change can be used to create a differential voltage output.

JCGM 200:2012 does not have a definition of a transmitter. Still, many industries know a transmitter to be a device that converts a low-level electrical signal from a sensor or transducer to a higher level or more sophisticated signal such a 4-20 mA or digital output. These outputs can transmit over long distances. Some transmitters can provide additional data about the device or process measured as part of the communication.

And the final output is...

The above devices are similar in that they provide a continuous signal whose values are related to the amount of pressure that the device is measuring. The final device category, the pressure switch, only change when crossing set pressure thresholds. Once the pressure crosses the set value, the switch opens or closes a circuit. The setpoints can indicate when the pressure of a system has dropped to low, like in an automobiles oil pressure system, turning on your check oil light, or made to indicate when pressure may be reaching unsafe high values, sounding an alarm for activating a vent to release excess pressure.