Advantages of LVDT | disadvantages of LVDT

This page covers advantages and disadvantages of LVDT. It mentions LVDT advantages or benefits and LVDT disadvantages or drawbacks.

Introduction:
As we know inductive transducers are used to measure displacement. The change in inductance can be caused due to below three factors.
• Change in the self inductance of coil.
• Change in the Mutual inductance
• Production of eddy current

There are two types of inductive transducers.
• LVDT-Linear Variable Differential Transformer
• RVDT-Rotary Variable Differential Transformer

The figure-1 depicts construction of LVDT. As shown primary winding is excited using alternating source. It generates alternating magnetic field (H) which induces alternating voltage to secondary windings by transformer action.

Benefits or advantages of LVDT

Following are the benefits or advantages of LVDT:
➨It measures displacement in the range from 1.25 mm to 250 mm.
➨It is free from losses due to friction.
➨It is not affected due to external environments.
➨It supports higher sensitivities in the order of 40 V/mm.
➨It has lower hysteresis loss.
➨It has lower power consumption (less than 1 Watt).

Drawbacks or disadvantages of LVDT

Following are the disadvantages of LVDT:
➨It is sensitive due to stray magnetic fields. Hence it needs to be protected from stray magnetic fields.
➨LVDTs are affected by temperature and vibration.
➨Demodulator circuit is needed to achieve DC output.
➨Dynamic response is limited due to mass of core (mechanically) and due to applied voltage (electrically).
➨To obtain appreciable differential output larger displacements are needed.

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What is difference between or comparison between

Following links mention comparison or difference between various equipments:
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