External PSU used, allows OD5 case to be smaller and isolates the mains voltage to make it safer. 120Va.c. or 240Va.c. operation and suitable for use with all a.c. LVDTs and most others Wide range span and zero control with both -10 to 10V and -20 to 20mA outputs. Gain and offset adjustment fully independent. Selectable transducer excitation frequency and load resistances Forward and reverse connection selection saves swapping wires in the connector. Housed in a robust die cast aluminum box with a 5-pin DIN connector. Half-bridge transducers accommodated with a simple plug wiring change.
Linear Variable Differential Transformers (LVDT)
These devices comprise a movable nickel iron core and three coils - one for energisation and two for pick-up. They need to be driven by a sine wave to produce an output amplitude and phase directly proportional to the position of the core with respect to the pick-up coils. A phase sensitive detector is required to demodulate the output signal. The main advantages of LVDTs are;
No wear problems as with potentiometers Infinite resolution, high accuracy and linearity No friction introduced into the measured system.