In-depth Tutorial on Linear Position Sensors (LVDTs)

What is An LVDT?The transformer's internal structure consists of a
The letters LVDT are an acronym for Linear Variableprimary winding centered between a pair of identically
Differential Transformer, a common type ofwound secondary windings, symmetrically spaced
electromechanical transducer that can convert theabout the primary. The coils are wound on a
rectilinear motion of an object to which it is coupledone-piece hollow form of thermally stable glass
mechanically into a corresponding electrical signal.reinforced polymer, encapsulated against moisture,
LVDT linear position sensors are readily available thatwrapped in a high permeability magnetic shield, and
can measure movements as small as a few millionthsthen secured in a cylindrical stainless steel housing.
of an inch up to several inches, but are also capableThis coil assembly is usually the stationary element of
of measuring positions up to ±20 inchesthe position sensor.
(±0.5 m).