Characteristics of LVDT

AIM:

To study the characteristics of LVDT Position sensor.

EQUIPMENTS REQUIRED:

LVDT Trainer Kit ,Multimeter , Patch chords

THEORY:

The most widely used inductive transducer to translate the linear motion into electrical signals is the linear variable differential transformer (LVDT). The basic construction of LVDT is shown in fig:

The transformer consists of a single primary P and two secondary windings S1 and S2 wound on a cylindrical former. The secondary windings have equal number of turns and are identically placed on either side. A moveable soft iron core is placed inside the transformer. The displacement to be measured is applied to the arm attached to the soft iron core. In practice the arm is made of highly permeability, nickel iron which is hydrogen annealed.

PROCEDURE:

1. Plug power chord to AC mains 230 V, 50 Hz and switch on the instrument. The display glows to indicate the instrument is ON.
2. Allow the instrument in ON position for 10 minutes for initial warm-up.
3. Balance the amplifier with the help of zero knob so that display should read zero (00.00) without connecting the LVDT to instrument.
4. Adjust the calibration point by rotating CAL knob so display should read +10.00 and – 10.00  ie., maximum calibration range.
5. Now the Instrument is calibrated for +/- 10.00 mm range. As the core of the LVDT moves the display reads the displacement in mm.
6. Rotate the core of the micrometer in steps of 3 and 4 and tabulate the readings. The micrometer will show the exact displacement given to the LVDT core & displays the displacement sensed by the LVDT.
7. Find out the voltage using multi meter. Tabulate the readings and plot the graph Actual Vs Indicated Reading.

OBSERVATION:

MODEL GRAPH:

RESULT:

Studied the characteristics of LVDT position sensor.