Failures In Electrical Systems, Causes & Prevention Introduction Electrical systems, equipments and materials are subjected to failures that can cause the total destruction of equipments and severe power outages. For this reason it is important to know main causes of those failures, their consequences and the procedures and tests to be performed in order to find the reasons why equipment …
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Why to use Shunt Reactors? Different between Power Transformer & Shunt Reactor What is Shunt Reactor? Shunt reactor is same as power transformer but it has only one winding per phase as compared to power transformer. Shunt reactors are used to increase the power and energy system efficiency as it absorb & compensate the reactive power in cables and long …
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Types of Transformers Insulation Materials Insulation in Oil-Immersed Transformers The most common insulation today for high-voltage windings in transformer is an enamel coating on the wire, with kraft paper used between layers. Low-voltage strip can be bare with paper insulation between layers. The use of paper wrapping on strap conductor is slowly being replaced by synthetic polymer coatings or wrapping …
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Power System Restoration – Power Outage & Restoring the Power Introduction Modern power grids are extremely complex and widespread. Surges in power overhead lines and other faults can cause massive network failures and permanent damage in power plants and in costumers’ equipments. If a network failure happens it is necessary to establish a program to restore power, avoiding the power …
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De-Energized Work procedure & Safety in Electrical Engineering Introduction Electricity presents to the workers and installations different hazards and for this reason local operations and maintenance of electrical equipment should only be performed after a detailed analysis of risk, definition of appropriated procedures and can only be done by instructed personnel to avoid emergency case. Policies & Procedures Each company …
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Electrical Shock Hazards & Effects What is Electrical Hazard? Electrical hazard or Electric Shock may be defined as “Dangerous event or condition due to direct or indirect electrical contact with energized conductor or equipment and from which a person may sustain electrical injury from shock, damage to workplace environment, damage to property or both. When working with or nearby electrical …
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Protective Actions to Reduce & Avoid Electric Hazardous General Rules As general safety rules for EHV, HV and MV installations (EHV: Extra High Voltage – V ≥ 150 kV. HV: High Voltage – 60 kV ≤ V < 150 kV. MV: Medium Voltage – 1 kV < V < 60 kV), those related physical with the protection of the site, …
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Electrical Transmission Networks and Overhead Lines Generally, EHV and HV (High Voltage; 60 kV ≤ V < 150 kV, EHV: Extra High Voltage; V ≥ 150 kV) is used for energy transmission to decrease the current in the line, what allows the reduction of the cross section of conductors and losses by Joule effect ( Joule law: W = RxI2xt …
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Busbars and Connectors in Indoor & Outdoor Installations What is Electric Busbar? A conductor or group of conductor used to collect the power from incoming feeders and distribute to the outgoing feeders is known as busbar. In other words, Busbar is a junction where the incoming and outgoing feeders current meets i.e. it collects the power at single point. Busbars …
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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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