What is Transducer | Classification Of Transducer | Different Types Of Transducer | Advantages Of Transducer

Table of Contents
What is Transducer
What is Transducer transducer is a device that converts one energy into another energy. Such energy can be electrical, mechanical, chemical, optical or thermal. If a transducer gives electrical energy at its output it is called an electrical transducer
Such electrical output can be voltage, current or frequency. Such signals are generated based on resistive, capacitive and inductive properties
The input level for most instrumentation systems is not electrical. If electrical methods are to be used for measurement, manipulation, or control, the non-electrical quantity must generally be converted using an Transducer
Basic Requirements Of Transducer
Linearity
The input output characteristics for the transducer must be linear
Ruggedness
Necessary safety measures should be taken to prevent any overload
Repeatability
In the same situation, the same output signal should be available when the same input signal is given at different times
High stability and reliability
Transducer output should not be affected by temperature, vibration and other climatic changes
Good Dynamic Response
Depending on the time, the output it gives should be equal to its input. This characteristic is taken as the frequency response
The transducer must provide the maximum analog output signal with the highest “signal to noise ratio”. The output can be measured directly or after the required amplification
Residual Deformation
It should not be disturbed even if the load is removed after using it for a long time
Types Of Transducer
- Resistive,inductive and capacitive transducers
- Primary and secondary transducers
- Active and passive transducers
- Analog and digital transducers
- Input and output transducers
- Direct and Inverse transducers
Classification Of Transducer
Transducers are divided into resistive, capacitive and inductive depending on their performance. They are further classified as piezoelectric, thermoelecric, optical, magnetorestritive
Active and Passive Transducers
Transducers are divided into active transducers and passive transducers according to their ability to convert energy
Active transducers generate an electrical signal directly depending on the physical parameter given to it. No power is required from outside for their operation
Active transducers get the energy they need from the system we are measuring. Therefore active transducers are also called self generating type transducers
Example
- Tachogenerators that measure angular velocity
- Thermocouples that measure temperature
- Piezoelectric crystal measuring force
If a transducer changes the value of electrical parameters such as resistance, inductance or capacitance depending on the input signal given to it, it is called passive transducer
Such transducers require external power to operate. Therefore, such transducers receive a small amount of energy from the measuring system
Such transducers are also called externally powered transducers. Examples Strain gauges, Thermistors
Primary and secondary transducers
Transducers are classified as primary and secondary transducers depending on the type of application. If a transducer senses the input signal given to it directly and converts its physical properties directly into electrical signal, it is called primary transducer
Example
The thermistor that measures the temperature senses the temperature directly and changes its resistance value according to the change in temperature
If a transducer converts the given input signal into an electrical signal by first sensing (perceiving) the given input signal through a detector or sensor, it is called a secondary transducer
Example: The bourdon tube acts as the primary sensor when measuring pressure. This converts the pressure into displacement. The LVDT then converts the displacement into an output voltage. In this method the LVDT is called the secondary transducer
ADVANTAGES OF TRANSDUCERS
- Electrical operations such as amplification and attenuation can be done easily
- Damage caused by friction is avoided
- Mass-inertia properties are reduced
- Very little power is enough to control an electrical or electronic system
- Electrical output can be amplified as required
- The output can be viewed and recorded even remotely from the sensing medium
- The output can be adjusted to suit the control units or the indicating units
- The signal can be generated by combining the output of another similar transducer or with the control signals in the required manner (scale)
- Electrical output is easy to measure, transmit and process
Also Read: OPERATIONAL AMPLIFIER IC 741