Instrumentation a perspective

摘要

Precision measurements are fundamental for any Instrumentation System. The techniques used to solve an instrumentation issue is more of an art than science. In many practical situations, the parameters to control the Instrumentation system is difficult to determine but are crucial for the success of any implementation scheme. In this presentation, I shall dwell on some Industrial Instrumentation problems, restricting my attention to systems using inductive, or capacitive parameters only, focusing on choice of parameters and the techniques of measurement to precisely control the process. Measurement problems exist all the time. One has to identify the parameters that determine the process and measure them accurately with out any ambiguity. I shall discuss first. A very low Capacitance measurement problem with a specific example to illustrate the methods to eliminate errors and obtain results accurately. One such measurement problem was referred to us by a Researcher, when studies were being made on the properties of DNA molecules. This problem was faced by a Research scholar at calcutta University and he has by then exhausted all the standard methods of capacitance measurement with disappointing results. By the time the problem arrived, fortunately, we were also working on capacitive transducers for a sensor array and we too faced the problems of stray capacitances and have eliminated most such effects successfully.