differential transformer

Also found in: Acronyms.

differential transformer

[‚dif·ə′ren·chəl tranz′fȯr·mər]
A transformer used to join two or more sources of signals to a common transmission line.

Differential transformer

An iron-core transformer with movable core. A differential transformer produces an electrical output voltage proportional to the displacement of the core. It is used to measure motion and to sense displacements. It is also used in measuring devices for force, pressure, and acceleration which are based on the conversion of the measured variable to a displacement.

Various available configurations, some translational and others rotational, all employ the basic circuit shown in the illustration: a primary winding, two secondary windings, and a movable core. The primary winding is energized with alternating voltage. The two secondary windings are connected in series opposition, so that the transformer output is the difference of the two secondary voltages. When the core is centered, the two secondary voltages are equal and the transformer output is zero. This is the balance or null position. When the core is displaced from the null point, the two secondary voltages are no longer alike and the transformer produces an output voltage. With proper design, the output voltage varies linearly with core position over a small range. Motion of the core in the opposite direction produces a similar effect with 180° phase reversal of the alternating output voltage. See Transducer, Transformer

Basic circuit of differential transformerenlarge picture
Basic circuit of differential transformer
References in periodicals archive ?
and consist of a brush type rare earth permanent magnet motor, a conventional spur geartrain, two bull gear / jackscrew combinations coupled together by a single spur gear, two drive nut/moveable output rams, and a feedback Rotary Variable Differential Transformer (RVDT).
linear variable differential transformers (LVDTs) for the measurement of linear displacement under temperatures up to 600 A[bar]C and pressures of 250 bar.
com/research/wmxzdj/position_sensors) has announced the addition of the "Position Sensors Market (2014-2020);By Application (Automotive, Food & Beverage, Medical); By Type ( Linear Variable Differential Transformers (LVDT), Rotary Variable Differential Transformers (RVDT)); By Technology (Hall Effect, Resistance-based, Ca" report to their offering.
PSD-based laser sensors are ideal for tire and rubber applications, and are replacing dial indicators, linear variable differential transformers, capacitive, inductive and ultrasonic sensors for these types of applications.
The company's technologies comprise piezoresistive silicon, polymer and ceramic piezoelectric materials, application specific integrated circuits, micro-electromechanical systems, foil strain gauges, electromagnetic force balance systems, fluid capacitive devices, linear and rotational variable differential transformers, anisotropic magneto-resistive devices, electromagnetic displacement sensors, hygroscopic capacitive structures, ultrasonic measurement systems, optical measurement systems, negative thermal coefficient ceramic sensors, 3-6 degree of freedom force/torque structures, complex mechanical resonators, magnetic reed switches, high frequency multipoint scanning algorithms, and high precision submersible hydrostatic level detection technologies.
uses laser triangulation to lock onto a point, and analog linear variable differential transformers (LVDT's) to determine the position of the probe axes.

Full browser ?