What Is a Galvanometer | Construction of Galvanometer | Working Principle of Galvanometer | Applications of Galvanometer

 Working Principle of Galvanometer

The galvanometer was augmented by the operation of the needle of a magnetic compass when it is brought to the electric wire. The Danish physicist and chemist first discovered in the year 1820 a small amount of current and a measurable device to create a magnetic field called ‘Hans Christian Ørsted’.

The first connection was between electricity and magnetic. Today in our article we will talk about why a galvanometer is built What is its working principle, its use, and much more.

What is a Galvanometer?


Definition: A galvanometer is an electromechanical instrument used to detect small currents and voltages. Such a device is called a galvanometer. Galvanometers are mostly used in bridges and potential mediums. Where they indicate null deflection or zero flow.

The first galvanometer could not be set but later devices called galvanometer development emitters were used to measure current. The main use of an emitter is to calculate the current flowing in an electric circuit.

This tool is used as a visualizing part in different types of analog meters. The best examples of analog meters are VU meters and light meters. This meter is used to calculate and display the output of any type of sensor.

Mainly moving coil, D’Arsonval / Weston type Galvanometer is used in various applications.

Also Read: What Is Lightning Arresters | Working Principle | Types Of Lightning Arresters

Galvanometer Construction:

The construction of the galvanometer is as shown in the figure below. The main parts include suspension, moving coil, and stationary magnet.

Moving Coil Galvanometer

#1. Moving Coil:

This is used in the galvanometer to carry current. This is made by counting the loops in the shape of a circle or rectangle. This coil rotates independently between the static magnet poles. The iron core provides a path of low reluctant current and therefore provides a strong magnetic field for the coil to go inside.

#2. Suspension:

The balance of the coil in the galvanometer is done with the help of a plane ribbon. The ribbon helps to provide current to the coil. The other coil that carries current is the lower suspension whose torque is equal to

The design of the upper suspension coil is made of gold wire or copper wire in the form of a ribbon. The mechanical strength of such a wire is not very strong which is why the galvanometer handles it carefully without any kind of stress.

#3. Mirror:

The suspension of the galvanometer uses a small mirror that reflects a ray of light located on a scale where deflection can be measured.

#4. Torsion head:

The torsion head is used to control the position of the coil and to adjust the zero setting.

Also Read: What is Contactor | Construction | Working Principle | Types and Applications

Working Principle of Galvanometer:

The main function of a galvanometer is to measure the presence, direction, and electric current in the conductor. This works on the principle of mechanical energy to electric energy.

Once the current is in the magnetic field after the supply is turned on, the magnetic torque can be realized. If it is open to rotating under the controlling torque, it is rotated by an angle that is proportional to the current flowing through it.

This is an ampere meter-type instrument used to measure and detect electric current.

Advantages of Galvanometer:

The advantages of galvanometer are as follows:

  • Is accurate and trustworthy.
  • Not affected by the strong magnetic field.
  • The scale is the same.

Disadvantages of Galvanometer:

The disadvantages of galvanometers are as follows:

  • Overwhelming causes it to damage the galvanometer.
  • This cannot be used for AC current measurement.
  • A change in temperature will change the restoring torque.
  • The torque cannot be easily changed.

Applications of Galvanometer:

The application of galvanometers are as follows:

  • This is used to determine the current.
  • This is done to find the direction of current in the circuit and also to determine the null point.
  • The voltage between two points can be easily determined.
  • They are used in control systems, laser engraving, laser TV, laser sintering, laser displays, etc.
  • It is also used to control the status of head servos in CD / DVD players and on hard drives.

Like this post? Share it with your friends!

Suggested Read –

Leave a Comment