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Three Phase AC Circuits

Corona Effect in Transmission Lines & Power System

A Full Guide about Corona Effect - Corona Discharge in Transmission Lines

A Full Guide about Corona Effect – Corona Discharge in Transmission Lines What is Corona or Corona Discharge? When an alternating potential difference is applied across two conductors whose spacing is large as compared to their diameters, there is no apparent change in the condition of atmospheric air surrounding the wires if the applied voltage is low. However, when the …

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Introduction to Harmonics – Effect of Harmonics on Power System

Introduction to Harmonics

What are Harmonics and How to Filter and Eliminate it. (Manuel Bolotinha) Introduction to Harmonics The quality of electrical power supply is an important issue both for utility companies and users, but that quality may affected by electromagnetic disturbances. Among these disturbances it must be highlighted harmonics that happens in all voltage levels and whose study, calculation of acceptable values …

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Short Circuit Currents And Symmetrical Components

Short Circuit Currents faults And Symmetrical Components

Short Circuit Currents And Symmetrical Components (Manuel Bolotinha) Short Circuit Faults and Currents Short-circuits can occur phase-to-phase and phase-to-earth, mainly due to: Dielectric breakdown of insulating materials (ageing, severe overheating and overvoltages, mechanical stress and chemical corrosion are the main factors for dielectric breakdown) Decrease of creepage distance (the shortest path between two conductive parts – or between a conductive …

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What is the Difference Between Neutral, Ground and Earth?

What is the Difference Between Neutral, Ground and Earth

The Main difference between Neutral, Ground and Earth? ‪To understand the difference between Neutral, Ground and Earth, we must understand the need of these things first. Neutral Neutral is return path for an AC circuit which is supposed to carry current in normal condition. This current may be because of many reasons, primarily because of phase current imbalance and some …

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Star and Delta Connected Lighting Loads

Star and Delta Connected Lighting Loads - Electrical Wiring Installation

Star and Delta Connected Lighting Loads – Electrical Wiring Installation Star (Y) Connected Lighting Load – Electrical Wiring A Star connected (Three Phase Four wires or 3-Phase, 4 wires) lighting system in a multi-storey (three Storey) building is shown in fig a. for uniform load distribution among three phases without being affected by random switching ON and OFF or burning lamps …

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Comparison between Star and Delta Connections

Comparison between Star and Delta Connections

Main Different between Star and Delta Connections Comparison between Star (Y) and Delta (Δ) Connections Star (Y) Connection Delta (Δ) Connection In STAR connection, the starting or finishing ends (Similar ends) of three coils are connected together to form the neutral point. A common wire is taken out from the neutral point which is called Neutral. In DELTA connection, the …

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Delta Connection (Δ): 3 Phase Power, Voltage & Current Values

Delta Connection (Δ) Three Phase Power, Voltage & Current Values

Delta Connection  (Δ) In this system of interconnection, the starting ends of the three phases or coils are connected to the finishing ends of the coil. Or the starting end of the first coil is connected to the finishing end of the second coil and so on (for all three coils) and it looks like a closed mesh or circuit …

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Star Connection (Y): Three Phase Power, Voltage & Current Values

Star Connection (Y): Three Phase Power, Voltage & Current Values

Star Connection (Y) In this kind of interconnection, the starting ends or finishing ends (Similar ends) of three coils are connected together to form the neutral point. Or Star Connection is obtained by connecting together similar ends of the three coils, either “Starting” or “finishing”. The other ends are joined to the line wires. The common point is called the …

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Three Phase Current Values in a 3-Phase System

Three Phase Current Values in a 3-Phase System. current in a poly phase system

Three Phase Current Values in a 3-Phase System The following points may be noted for understanding the division of Three Phase Current in a 3-Phase System       1.  The arrow symbols shown alongside three phase current (IR, IY and IB) in fig 1 and 2 does not indicate the currents directions in a particular moment but shows the current directions …

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Rated characteristics of Electrical Contactors

Electric Magnetic Contactor Thermal Overload relay

Rated characteristics of Electrical Contactors Click image to enlarge 1. Types: (i) Electromagnetic (ii) Electro-pneumatic (iii) Pneumatic Important Terms and Definitions related to Motor Control and Protection 2. Interrupting Medium: (i) Air (ii) Oil (iii) SF6 gas (iv) Vacuum Abnormal Operating Condition and Causes of Induction Motors 3. Rated values of voltages: (i) Rated voltage (Operational voltage) For a three …

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