any one of the technical devices that have standardized metrological properties and are used to carry out the experimental part of measuring work. Measuring agents include measures, measuring instruments, measuring transducers, and installations and systems made up of these components. They are calibrated in the units in which the measured quantity is to be expressed. Their operating principles vary widely because of the great diversity in the values to be measured. They may be based on, for example, mechanical, electrical, electronic, magnetic, optical, thermal, and chemical phenomena and on combinations of these phenomena. Many types of measuring agents are grouped according to the class of precision. Semiautomatic and automatic measuring agents are coming into wider use because they accelerate the measuring work and require less labor. In addition to taking measurements, measuring agents are also widely used for control, signalization, and regulation, for monitoring production processes, and for collecting various types of information for processing by computers.
REFERENCEBurdun, G. D., and B. N. Markov. Osnovv metrologii. Moscow, 1972.
K. P. SHIROKOV