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Failures In Electrical Systems, Equipments & Materials

Failures In Electrical Systems, Equipments & Materials

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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Power System Restoration – Outage, Voltage Collapse & Switching Programs

Power System Restoration - Outage, Voltage Collapse & Switching Programs

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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Working on De-Energized Electric Circuits, Networks & Equipments

Working on De-Energized Electric Circuits, Networks & Equipments

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 & Its Effects on Human Body

Electrical Shock Hazards & Effects on Human Body

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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Treeing in XLPE Insulated Medium & High Voltage Cables

Treeing in a XLPE insulated cable

Electrical Treeing in XLPE Insulated MV & HV Cables (Manuel Bolotinha) Nowadays XLPE (Cross-linkedpolyethylene) is the most used insulation material of medium and high voltage cables, which presents important advantages over PVC (Polyvinylchloride) and other insulations materials. Main advantages of XLPE are: Thermal stability High dielectric strength and insulation resistance Lower losses (tan δ) Stability to ageing Allows more current carrying …

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MV & HV Cable Termination to Equipment & Joints

MV & HV Cable Termination to Equipment

Medium & High Voltage (MV & HV) Cable Termination & Joints General Problems & Factors for Termination Terminations to indoor switchgears, electric motors, power transformers, instrument transformers and other electrical MV and HV (MV: Medium Voltage; 1 kV < V < 60 kV. HV: High Voltage: V ≥ 60 kV) equipment issues arising for multiple terminations design, namely for switchgears, …

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Types & Characteristics of Surge Arresters

Lightning protection wires

Surge Arresters – Types & Characteristics Introduction Atmospheric lightning phenomenon on overhead lines and bare conductors or metallic structures of an outdoors substation and over voltages due to switching operations of equipments and networks (switching over voltages) can cause serious hazards to equipment. To protect the equipments and to aid insulation coordination surge arresters, also called “lightning arresters”, must be …

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