Static Distance Protection Relay: Static Distance Protection Relay are characterized by having two input quantities respectively proportional to the voltage and current at a particular point in the power system,…
Basic Elements of Static Relay: The basic elements of a static relay are namely, Input Element: Mixing circuits are needed to sum the input signals in a convenient form. Semiconductor…
Static Relays Basics and Classification: A Static Relays Basics refers to a relay in which the measurement or comparison of electrical quantities is done in a static network which is…
Directional Relays: Selective protection cannot be achieved with time graded overcurrent protection systems in ring or loop systems as well as in radial circuits with two end power supply. A…
Important Questions of Characteristics of Electric Motors: Problems of Characteristics of Electric Motors: 1.A 50 hp, 220 V, 1200 rpm dc shunt motor has an efficiency of 85% at full…
Optocoupler Circuit Operation: An Optocoupler Circuit Operation (optoelectronic coupler) is essentially a photo-transistor and an LED combined in one package. Figure 20-35(a) and (b) shows the typical circuit and terminal…
Photoconductive Cell Construction and Working: Photoconductive Cell Construction and Working - Light striking the surface of a material can provide sufficient energy to cause electrons within the material to break…
UJT Circuit Diagram: UJT Circuit Diagram Operation : The Unijunction transistor (UJT) consists of a bar of lightly-doped n-type silicon with a block of p-type material on one side, [see…