Working principle of Analog Instruments

The analog instruments can be categorized according to the principle of operation. The following are the effect uses the analog instrument for their operation.

Magnetic Effect

The magnetic effect means the current flows through the conductor induces the magnetic field around it. For example, consider the conductor is converted into the coil. The summation of the magnetic field of the coils will behave as an imaginary magnet.

Thermal Effect

The measurand current passes through the heating elements increases their temperature. The thermocouple attached to the element converts the temperature into an emf. The conversion of the current into an emf with the help of temperature is known as the thermal effect.  

Electrostatic Effect

The electrostatic force exerted between the two charged plates. This force is used for displacing one of the plates. The instruments which work on this principle is known as the electrostatic devices.

Induction Effect

The non-magnetic conducting disc placed in a magnetic field induces an electromotive force. This magnetic field is induced by the electromagnet which is excited by the alternating current. The electromotive force induces the electric current insides the drums. The interaction produced by the induced current and the emf moves the disc. This effect is mostly used in the induction effects.

Hall Effect

Suppose a material is carrying a DC current and placed in a magnetic field perpendicular to the applied current, then it produces a voltage difference across a material transverse to the applied current. the voltage produced is called the hall voltage.