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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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 (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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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 – 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 …
Read More »Comparison between Star and Delta Connections We mostly use the terms star and delta in electrical systems while discussing three phase AC circuits and electric motors. Below is a given table which compares both Star and delta connections showing the exact difference between Star (Y) and Delta (Δ) Connections. Star (Y) Connection Delta (Δ) Connection In STAR connection, the starting …
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Three Phase Delta Connection: Line, Phase Current, Voltages & Power in Δ Configuration What is Delta Connection (Δ)? Delta or Mesh Connection (Δ) System is also known as Three Phase Three Wire System (3-Phase 3 Wire) and it is the most preferred system for AC power transmission while for distribution, Star connection is generally used. In Delta (also denoted by Δ) …
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Three Phase Star Connection: Line, Phase Current, Voltages & Power in Y Configuration What is Star Connection (Y)? Star Connection (Y) System is also known as Three Phase Four Wire System (3-Phase 4 Wire) and it is the most preferred system for AC power distribution while for transmission, Delta connection is generally used. In Star (also denoted by Y) system …
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Division of 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 …
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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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