Sample specification of a displacement transducer is given below,
Sliding resistance wire
- Capacity – 30 mm….300 mm
- Non-linearity – 0.2
- Rated output – 1.5, ±1%
LVDT
- Capacity – 0 to 50 mm
- Non-linearity – Linearity over small displacement
- Any other – Accuracy 0.1 % of range
RVDT
- Capacity – 40
- Non-linearity – Linearity over small displacement
- Any other – Accuracy 0.1 % of range
Dial gauge type
- Capacity – 5 mm… .. 30 mm
- Non-linearity – 0.5
- Rated output – 0.5, 1, 1.5, ±20%
SELECTION OF DISPLACEMENT TRANSDUCER
The following factors should be considered when selecting a displacement transducer.
- Required accuracy.
- Resolution required.
- Size of displacement.
- Type of displacement.
- Cost of transducer.
- Material used for transducer.
APPLICATIONS OF DISPLACEMENT TRANSDUCER
- Applications of displacement transducers such as Potentiometer, LVDT, RVDT etc. are given below.
- LVDT can be used in all displacement measurements, where displacement ranges from fraction of mm to few centimetres.
- LVDT is used in CNC machines for displacement measurement.
- LVDT can be used for measurement and control of thickness of a metal sheet being rolled.
- Used for measurement of tension in channel.
- RVDT is used in flight control system.
- Potentiometer is used in design of many transducers for measurement of pressure, force and acceleration.
- Potentiometer can be used as a position feedback in servomechanism.
- Acting as a secondary transducer, displacement transducer can be used as a device to measure force, weight, pressure etc.
