ABSTRACT
Kelvin’s first rule of instrumentation states, in essence, that the measuring instrument must not alter the event being measured. For the present purposes, we can consider the instrument to consist of an input transducer followed by a signal-conditioning section, which in turn drives the data-processing and display section (the remainder of the instrument). We are using the term
instrument
in the broad sense, with the understanding that it may actually be a measurement subsystem within virtually any type of system.
