Public Street & Road Lighting – General Principles, ISO & IEC Standards Lighting Basic Parameters Basic parameters used in lighting are: Luminous flux – notation: Φ ; unit: lumen ( lm ). Luminous intensity – notation: I; unit: candela ( cd ). Illuminance – notation: E; unit: lux ( lx or lux ). Luminance – notation: L; unit: cd / …
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Cables Feeder Protection – Overcurrent & Differential Protection Common Types of Faults Common failure modes and faults of cables are: Electrically induced failures Mechanically induced failures Thermally induced failures Metallic (semiconducting) shield damage Poor Metallic Shield Contact Explanation of each fault is follow respectively. Electrically induced failures These involve lightning, switching surges, and partial discharges. Partial discharges may be caused …
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Overhead Lines Faults & Protection in Power System Common Faults in Overhead Lines The most common causes of faults in overhead lines are: Aircraft and cars hitting lines and structures Birds and animals Contaminated insulators Ice and snow loading Lightning Partial discharges (corona) not controlled Punctured or broken insulators Trees Wind Related Article: Power Transformer Protection & Faults Overhead Lines …
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Types and Configurations of EHV/EHV and EHV/HV Substations The Role of EHV/EHV and EHV/HV Substations in Transmission Network EHV/EHV and EHV/HV[1] substations are an important element of the electricity transmission network of a country or of a large area of a country and their functions are: Interconnection of power plants of the national or area electrical grid. Step up and …
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Electrical Protection Units And Systems Introduction to Electrical Protection Systems HV, MV and LV[1] electric installations and equipments are subjected to internal and external faults that can cause serious damages in persons and other equipments. To avoid and to minimize the consequences of those faults protection devices associated to equipments that are able to break electric current are required. For …
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Maintenance of Power Transformer – Transformer Diagnostic and Monitoring Introduction Being transformers static machines without any moving and turning parts, they are very reliable machines, and if maintained properly, can last for 40 years or more. Also they do not trip or blow when oven-stressed (except under extreme conditions), transformers are frequently overloaded and allowed to operate well beyond its …
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An Introduction to Insulating And Dielectric Materials Definition of Insulating and Dielectric Materials An electrical insulating material can be defined as the material that does not allow electric current to pass through it. For electrical applications a particular category of insulating materials is used to separate electrically the conducting parts of equipment from each other and from earthed and “no …
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Basic Requirements for Transformers Fire Protection System By: Manuel Bolotinha Causes of Fire in Transformers Excessive overheating, extremely severe short circuits, faults in the oil and lightning strokes may cause a fire on transformers. Transformer fires are rare but the impact is great. Even though a transformer involved in a fire likely will be destroyed almost immediately, as seen in …
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An Introduction to Submarine Cables & Subsea Power Cables Introduction to Submarine Cables The development of offshore wind farms and oil and gas offshore platforms requires the installation of power, control and monitoring and communications cables between the platforms and the main land. For this purpose submarine cables are installed, which are also used for power and/or communications between islands …
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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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