SENSOR OPPORTUNITIES: LVIT technology offers more flexibility for less money in factory automation applications

摘要

What is an LVIT and where is it used? LVTTs - Linear Variable Inductive Transducers - which have been around for more than 30 years, are relatively low cost, contactless position sensing devices that utilize eddy currents developed by an inductor in the surface of a conductive movable element that is mechanically coupled to the moving object whose position is being measured. The common form of an LVIT uses a small diameter inductive probe surrounded by a conductive tube called a spoiler. Typical LVTTs have full ranges from fractions of an inch to 30 or more inches. Modern electronics utilizing microprocessors make possible outstanding performance, achieving linearity errors of less than ±0.15 per cent of FSO and temperature coefficients of 50 ppm/℉, along with either analogue or digital outputs. See Figure 1 for a cutaway view.