Bornika Articles

Relay Test Device type PW636I has 4 output 300V and 6 output 32A can test all types of protective relays, including modern IEC61850 based relays. This device is the ideal test device for all power utilities , power plants , relay manufactures , panel manufactures , research institutes , testing companies. In this paper, we intend to have an overview of the device and its components.

A relay is an electrically operated switch. Many relays use an electromagnet to mechanically operate a switch, but other operating principles are also used, such as solid-state relays. Relays are used where it is necessary to control a circuit by a separate low-power signal, or where several circuits must be controlled by one signal.

Any internal fault inside the stator winding is cleared by mainly differential protection scheme of the generator or alternator.The differential protection is provided in the generator by using longitudinal differential relay.

Distance protection relay is the name given to the protection, whose action depends on the distance of the feeding point to the fault. IF the distance which is measured is less than the considered value for relay, the relay will protect the system and operate. Only by using the Distance relay, all faults in any location of system can be cleared. So, Distance relays are the best relays for protecting transmission energy systems. Even in high voltage and medium voltage systems, Distance relays are used.

Lightning surges frequently invade the electronic systems through AC power supplies, it is necessary to install the surge protective devices (SPDs) on the supply lines to protect the electronic equipment against lightning overvoltages.

In three phase transformer, it is essential to carry out a vector group test of transformer. Proper vector grouping in a transformer is an essential criteria for parallel operation of transformers. There are several internal connection of three phase transformer are available in market. These several connections gives various magnitudes and phase of the secondary voltage; the magnitude can be adjusted for parallel operation by suitable choice of turn ratio, but the phase divergence can not be compensated. So we have to choose those transformer for parallel operation whose phase sequence and phase divergence are same. All the transformers with same vector group have same phase sequence and phase divergence between primary and secondary. So before procuring one electrical power transformer, one should ensure the vector group of the transformer, whether it will be matched with his or her existing system or not.

For confirming the specifications and performances of an electrical power transformer it has to go through numbers of testing procedures. Transformer is one of the important equipment in power system. So, testing the transformer is pretty serious issue.In this paper, the different types of transformer testing are mentioned.

Switch-mode Power Supplies, are electronic power equipment, which include switching controller, for converting electric power to another voltage level. Switch-mode Power Supplies (SMPS) like other power supplies can be connected to one bigger source and transform energy to loads by different currents and voltages. Unlike linear power supplies, power transistors of switch-mode Power Supplies turn on and off, constantly, and as a result, these equipment have minimum loss power.

For the first time in the 1962 edition of the National Electrical Code standard and connected to the earth system is explained in the pool.

Different methods for attracting lightning conductors installed in air terminals (lightning protection system) that includes methods for protection angle, the ball is rolling and mesh.

On the surface, analog or analog multimeters are usually graded a number of lines, a hand that can move the dial lines, a selector, a number of terminals, the potentiometer adjustment of zero and two-wire interface is formed.

Azarayshy Harmonic filter using capacitors, inductors and resistors harmonic currents are directed to the ground. Hrfyltrharmvnyk can be formed from many elements, each of which is used to transfer the land harmonic multiples.