Chapter 11 - Intelligent sensors

Abstract

This chapter introduces the subject of intelligent sensors and devices, which are distinguished from their nonintelligent counterparts by their computational processing capability. The discussion starts with a brief review of the main principles of digital computation and how the computation element in an intelligent device interfaces with other measurement system components. Intelligent devices have a number of names, including intelligent instrument, intelligent sensor, smart sensor, and smart transmitter, but because there is no universal definition of these terms, devices with similar attributes but from different manufacturers may have varying names. The chapter summarizes the common features of intelligent devices and explains the significant advantages that they have compared with nonintelligent devices, particular with respect to improved measurement accuracy and their ability to perform functions such as remote self-calibration and self-diagnosis of faults. This is followed by a discussion of issues regarding communication between intelligent devices and other elements in a measurement/process control system, with coverage of local area networks and digital fieldbuses.