Measurement of earth resistance by fall of potential method

On these factors the resistance of earthing system are depends- Shape and material of electrode or electrodes used. Depth in the soil at which the electrodes are buried. Specific resistance of soil surrounding and in the neighborhood of electrodes. The specific resistance of the soil varies from one type of soil to another type of soil. Means its… Read More »

Construction of single-phase transformers

Construction of single-phase transformers- A single-phase transformer consists of two winding, called primary and secondary windings mounted on a magnetic core. To confine flux to a definite path magnetic flux is used. Transformer cores are made from thin sheets (called lamination) of high-grade silicon steel. The laminations reduce eddy-current loss and the silicon steel reduces hysteresis loss. The… Read More »

Shaded pole starting of a single phase induction motor

Shaded pole starting of a single phase induction motor- The single phase induction motors are self starting by providing additional flux by some additional means. Now we depending upon these additional means the single-phase induction motor classified as shaded pole induction motor.The single phase induction motors are self starting by providing additional flux by some additional means. Now we depending… Read More »

Operation and construction of Enhancement type Mosfet

At its name indicates, this MOSFET operates only in the enhancement mode & has no depletion mode. It works with large positive gate voltages only. It differs in construction from the DEMOSFET in that structurally there exists no channel between the drain & source” which shown in figure below. Hence it does not conduct when VGS=0 i.e. why… Read More »

Class B Power Amplifier

Class B amplifier is a type of power amplifier where the active device (transistor) conducts only for half cycle obey input signal. That means the conduction angle is 180 degree for a class B amplifier. Since the active device is switched off for half the input cycle, the active device dissipates less power hence the efficiency is improved.… Read More »

Frequency response of OP-AMP

OP-AMP Bandwidth, frequency response & gain bandwidth product are key parameters for any circuit. Typically, OP-AMPs are used for comparatively low frequency circuit but with the performance of these chips is improving all the time, much higher bandwidth OP-AMPs are available. The frequency response response of a typical OP-AMP chip will often start to fall at a very… Read More »

Types of Insulators

The successful operation of an overhead line depends to a considerable extent upon the proper selection of insulation. There are several types of insulators but the most commonly used are pin type, strain insulator, shackle insulator and suspension type. Pin type insulator Suspension type insulator Strain insulator Shackle insulator Pin type insulator- As the name suggests, the pin… Read More »