One of the most common types of transducers used for measuring pressure is the strain gauge pressure transducer. Relatively simple in design, this is a component that can provide highly accurate readings by converting the pressure in a given system into an electrical signal. This analog signal is read by a computer or other device, allowing for continual measurement or as changes occur in the system.
How it Works
In general, the strain gauge pressure transducer works the same as all other transducers. There is a diaphragm that is deformed when the pressure from the fluid from the pressure port exerts more or less. This causes the diaphragm to move in or out and triggers the transducer to convert this change into an electrical signal in millivolts.
The actual movement is sensed by strain gauges that are attached to the diaphragm. The gauges themselves are configured in what is known as a Wheatstone bridge configuration. This is a special configuration of an electric circuit allows for extremely accurate readings in all types of pressures and temperature.
The electrical signal generated through the circuit is then read by the system and converted into a specific number that can be displayed on a panel or stored in a database or software program.
The Benefits
There are several advantages to using the strain gauge pressure transducer. There are also several different types in use that are highly specific for unique types of applications.
In general, the strain-gauge transducer is very fast to respond to any slight changes in the pressure in the system. While all transducers and transmitters will be set to specific ranges, the speed of response within those ranges is critical for accurate measurements in testing and laboratory use.
The design of these types of transducers also makes them lower cost to produce, which translates into lower costs for end users. However, the lower cost does not cause a compromise in either performance or durability.
In the past, the biggest concern with the strain-gauge transducer was drift, which was particularly problematic in extreme temperatures. New technology and advancements in design and materials have greatly reduced this factor.
Today, these transducers are considered a very good option for many general use as well as specialty types of applications. They are very resistant to shock and vibration and can be used in pumps, hydraulic systems, pneumatic systems and even in engine and vehicle testing programs.