Practical aspects of transducer application

In selecting transducers to use in a given application, it is not enough merely to consult the catalogues and choose one having the right range—‐even when this is known initially. It is important to have regard to the parameter to be read and the method of connecting the transducer (in as far as its place of sensing is concerned) and to consider how the interface with the read–out equipment is to be effected. This choice may also be affected by the method chosen for display and/or recording. Such is the field covered by this article, which does not deal with the design of transducers—‐except where this conditions their suitability for the particular measurements—‐nor is their manufacture or calibration a subject of comment. Because the writer has been mainly concerned with development testing, particularly of aeroengines, the article will deal primarily with such measurements as represent transient, pulsating or vibratory effects and less with steady state checks. Many of the precautions—‐but not all—‐that are mentioned, are relevant also to the latter cases. Measurements at frequencies over 5 Hz are thus implied, unless otherwise stated.