When it comes to measuring pressure sensors, the word "accuracy" becomes quite arbitrary. Accuracy isn't defined by any one set standard, and it becomes more of a qualitative measure than a quantitative one. Several factors contribute to the overall measurement of accuracy. However, these can be inconsistent across manufacturers, so it's important to understand these factors and how they suit your needs before you make the decision about the ideal pressure sensor.
Nonlinearity is usually the main characteristic considered. It describes the curve on a graph that the sensor would produce in comparison to the ideal line (which is, of course, straight). However, even with nonlinearity graphs, it's not always possible to carry out a direct comparison. A graph could be created according to limit-point adjustment or by using the best-fit straight line method. Therefore, all data isn't consistent and can't be fairly compared. The cycle of hysteresis is also seen within pressure sensors and can contribute to their (in)accuracy.
Another uncontrollable factor is nonrepeatability. This is defined as the difference between the largest and smallest measurements, taken several times under fixed conditions, and it is present in every pressure sensor. It's how you measure these results that's important. So long as you test different level sensors under controlled conditions, you can make a fair comparison and decide which is best for you. No sensor will be completely perfect, and errors are to be expected. You just have to choose a level sensor that has the correct degree of accuracy for your needs, based on any available data.
— Nick Murden is a keen writer who helps businesses put thoughts into words. He is currently writing for a number of engineering firms around the UK, including TC Fluid Control.