LVDT-AC Operation

The basic design of an LVDT comprises a primary coil winding and two identical secondary windings on a common bobbin, and a moveable magnetic core. The primary winding of the LVDT is excited with a low voltage AC supply. The two secondary windings are connected so that their combined output represents the difference in the voltage induced into them. With the armature in the central position, the output is zero. Movement of the armature from this position produces an output which changes in phase and magnitude according to the armature displacement. The LAT is a compact, AC energized high performance transducer. It will deliver its best performance when energized with between 0.5 Vac and 7 Vac at 5KHz using a high quality carrier amplifier. The LOT transducer operates from simple unregulated power supplies of+20 to +40 Vdc or dual +/-10 to +/-20 Vdc and generates two 5 Vdc anti-phase output signals.