Pressure gauges, defined in the simplest way possible, are instruments used to measure and display pressure. Although all pressure gauges record the same thing, there are still several types of gauges used in various fields. For better or worse there are several factors that determine whether or not a specific gauge should be used in the field. Take, for example, one of the oldest, and still the most popular, Bourdon pressure gauge. The first models of these have existed over a hundred years, whereas now there are digital pressure gauges that are beginning to come into competition with this classic style. Both have their positives and negatives and we intend on exposing them for their similarities and differences in order to give a better understanding on which type of pressure gauge is right for you.
Digital Pressure Gauge
When using pressure transducers, digital pressure gauges provide a highly reliable and accurate reading, which can be clearly read on a digital screen. Unlike other types of pressure gauges, the digital pressure gauge gives you the option to change the unit reading. In addition to this feature, the majority of digital pressure gauges also have innovative features such as being able to tare or peak hold. Overall, these devices are more durable and reliable in harsher conditions because they do have mechanical pieces that can be affected by extreme heat or cold. Dial or mechanical analog pressure gauges, such as the Bourdon tube, will constantly need to be maintained because parts, usually the spring, need to be recalibrated in order to provide accurate results.
Digital pressure gauges are traditionally constructed in a Wheatstone bridge circuit and are operated through piezoresistive technology and read the pressure applied from the device’s diaphragm. What is measured on the Wheatstone circuit is the resistance to pressure, which converts proportionately to the amount of applied pressure.
Aforementioned, the Bourdon Tube is the most common dial gauge device that is used, and operates mechanically by several gears and parts working together. Compared to the digital gauge, Bourdon tubes are more susceptible to give inaccurate readings due to their mechanical make up, as well as being susceptible to shock resistance and vibration. Another problem is that Bourdon tubes are bad at giving low pressure readings. Along with giving poor readings, the device’s springs will eventually become unwound and will need to be worked on in order to provide consistent readings, however that happens after an extended period of use. When new, the tubes provide consistent readings and are highly sensitive. Although they cannot simply switch to different kinds of pressure readings, they are available in them separately and come at a much cheaper price compared to digital pressure gauges.