Instrument reliability is another important performance index pursued by instrument workers in chemical industry groups. Reliability and instrument maintenance are mutually reinforcing. High instrument reliability introduces a small amount of instrument maintenance, whereas poor instrument reliability results in a large amount of instrument maintenance. For chemical group inspection and process limit instruments, most of them are installed on process pipelines, various towers, kettles, tanks, and devices. Moreover, the continuity of chemical production, and most toxic, flammable, and explosive environments, these adverse factors add many difficulties to instrument maintenance. One is to consider the safety of chemical production, and the other is related to the personal safety of instrument maintenance personnel, Therefore, the consumption inspection and process limitation instruments of Chemical Industry Group require the maintenance amount to be as small as possible, which means that the reliability of the instruments should be as high as possible.
With the upgrading of instruments, especially the introduction of microelectronics technology into the instrument manufacturing industry, the predictability of instruments has greatly improved. Instrument manufacturers are also paying more and more attention to this performance index, and usually use the mean time between failures (MTBF) to describe the reliability of the instrument. The MTBF of a fully intelligent transmitter is about 10 times higher than that of general non intelligent instruments such as electric III transmitter, and it can be as high as 100-390 years.
