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ABB launches new generation 420kV gas insulated switchgear

Compact design reduces volume by up to 33 percent and lowers environmental impact ABB's latest generation 420 kV GIS (April 2012) Zurich, Switzerland, April 23, 2012 – ABB, the leading power and automation technology group, announced the launch of its new generation 420kV (kilovolt) Gas Insulated Switchgear (GIS) at the Hannover Fair being held in Germany from 23-27 April 2012. The new... [Read more]

Superconducting transformers

Superconducting transformers

100 kA Superconducting Transformer In a superconducting transformer the windings, made of a high temperature superconducting material (HTS), are cooled with liquid nitrogen at about 77K so that the resistance is almost negligible. Load losses, even after adding losses from nitrogen processing, can be reduced by 50%. The use of HTS transformers on a larger scale is economically justified and will become... [Read more]

Largest Tesla Coil Ever Built

The Colorado Springs lab possessed the largest Tesla Coil ever built, known as the “Magnifying Transmitter”. This was not identical to the classic Tesla Coil. According to accounts, Tesla managed to transmit tens of thousands of watts of power without wires using the magnifier. Tesla posted a large fence around the coil with a sign, “Keep Out – Great Danger”. Tesla’s... [Read more]

ePlusMenuCAD 10 RC1 – New Release

Good thing is that CsanyiGroup (author of ePlusMenuCAD) has prepared great price for RC1 – 150EUR or $198, which is double less than earlier version 9. By purchasing licence for ePlusMenuCAD 10 RC1 you will get complete version (when released) for free. When complete version come out, price will be like before 290EUR or $38. Read the full story at EEP – Electrical Engineering Portal ePlusMenuCAD... [Read more]

ABB Power Transformers – A guide to manufacturing

ABB is a major transformer manufacturer throughout the world. ABB power transformers are built and designed to meet the individual customer’s needs. This experienced attendance to details lies behind the success of ABB’s transformers. This approach is carried throughout the manufacturing process: design, core, winding, drying, tank, quality assurance, assembly, testing, transport and... [Read more]

Light Pollution

Light Pollution

Figure 1.1 Los Angeles, 1908 Light pollution or sky glow is caused by light aimed directly up into the sky and by light reflected off the ground or objects. Sky glow prevents the general public and astronomers from seeing the stars. Floodlights, wall packs and other un-shielded luminaires are the major contributors to sky glow. Overlighting, even with shielded luminaires, reflects unnecessary light... [Read more]

Line Protection With Distance Relays

Line Protection With Distance Relays

Line Protection With Distance Relays Distance relaying should be considered when overcurrent relaying is too slow or is not selective. Distance relays are generally used for phase-fault primary and back-up protection on subtransmission lines, and on transmission lines where high-speed automatic reclosing is not necessary to maintain stability and where the short time delay for end-zone faults can be... [Read more]

UPS design criteria and selection

UPS design criteria and selection

UPS design criteria and selection An UPS system is an alternate or backup source of power with the electric utility company being the primary source. The UPS provides protection of load against line frequency variations, elimination of power line noise and voltage transients, voltage regulation, and uninterruptible power for critical loads during failures of normal utility source. An UPS can be considered... [Read more]

The New ETS4: Easy, Fast, Open

The New ETS4: Easy, Fast, Open

The New ETS4: Easy, Fast, Open Singapore, Los Angeles, Johannesburg, London, Berlin, Moscow – building automation engineers from all over the world, use ETS as product and manufacturer independent programming tool in order to increase energy efficiency of buildings. This standardised tool is currently available in 15 languages, and supports KNX installations for all media: twisted pair, radio frequency,... [Read more]

Arc-resistant low voltage switchgear

Arc-resistant low voltage switchgear

Arc-resistant low voltage switchgear For years, electrical equipment has been designed to withstand and deal with the issue of bolted faults, where the current spikes to a dangerously high level but is safely interrupted by the protective devices contained in the equipment (breakers, fuses and relays). However, these devices typically do not detect and interrupt dangerous internal arcing faults, which... [Read more]

What is PowerLogic System?

What is PowerLogic System?

PowerLogic System lets you optimise the cost, quality and reliability of an electrical installation. It combines communicating devices with power monitoring software operating under Windows. PowerLogic System provides information on the entire electrical installation. It offers a wide range of possibilities and can carry out a number of tasks including: - alarm processing - automatic tasks (e.g. automatic... [Read more]

Introduction To Micro Hydropower

Introduction To Micro Hydropower

Fig 1 - General layout of a hydropower plant A hydroelectric plant converts the potential energy of water into electricity by the use of flowing water. This water flows in water streams with different slopes giving rise to different potential for creating heads (size of fall), varying from river to river. The capacity (power) of a plant depends on the head (change in level) and flow as a result of... [Read more]

Visual Inspection Of The Oil Transformer

Visual Inspection Of The Oil Transformer

1.1 Background Visual inspection of the transformer exterior reveals important condition information. For example, valves positioned incorrectly, plugged radiators, stuck temperature indicators and level gauges, and noisy oil pumps or fans. Oil leaks can often be seen which indicate a potential for oil contamination, loss of insulation, or environmental problems. Physical inspection requires staff... [Read more]

Substation, Its Function And Types

Substation, Its Function And Types

Substation, Its Function And Types An electrical sub-station is an assemblage of electrical components including busbars, switchgear, power transformers, auxiliaries etc. These components are connected in a definite sequence such that a circuit can be switched off during normal operation by manual command and also automatically during abnormal conditions such as short-circuit. Basically an electrical... [Read more]

General about motors

General about motors

ABB - General about motors Modern electrical motors are available in many different forms, such as single phase motors, three-phase motors, brake motors, synchronous motors, asynchronous motors, special customised motors, two speed motors, three speed motors, and so on, all with their own performance and characteristics. For each type of motor there are many different mounting arrangements, for example... [Read more]

Current Switching with High Voltage Air Disconnector

Current Switching with High Voltage Air Disconnector

Current Switching with High Voltage Air Disconnector In the paper are presented results of switching overvoltages investigations, produced by operations of air disconnector rated voltage 220 kV. Measurements of these switching overvoltages are performed in the air-insulated substation HPP Grabovica on River Neretva, which is an important object for operation of electric power system of Bosnia and Herzegovina. Investigations... [Read more]

Shielding Of Power Cables

Shielding Of Power Cables

Shielding Of Power Cables Shielding of an electric power cable is accomplished by surrounding the assembly or insulation with a grounded, conducting medium. This confines the dielectric field to the inside of this shield. Two distinct types of shields are used: - Metallic - Nonmetallic . . The purposes of the insulation shield are to: Obtain symmetrical radial stress distribution withh the insulation. Eliminate... [Read more]

History Of The Power Substations

History Of The Power Substations

Figure 1: Three generations of transformer substations Early transformers were located at the top of pylons and could achieve powers of up to 1000kVA. Column-type transformer substations provided the interface between overhead and underground networks. These were equipped essentially with air-insulated MV switchgear, a liquid- insulated transformer and a low voltage distribution switchboard. These... [Read more]

Corona ions (air ionisation)

Corona ions (air ionisation)

Corona ions (air ionisation) The intense electric field on the surface of powerline cables is sufficient to ionise the air, producing corona ions. This process is the cause of the characteristic buzzing or crackling of powerlines. Corona ions are routinely emitted from high voltage powerlines, especially in wet conditions. Corona ion effects have been measured up to 7 kilometres from powerlines both... [Read more]

The Power Factor

The Power Factor

The Power Factor Correction The power factor of a load, which may be a single power-consuming item, or a number of items (for example an entire installation), is given by the ratio of P/S i.e. kW divided by kVA at any given moment. The value of a power factor will range from 0 to 1. If currents and voltages are perfectly sinusoidal signals, power factor equals cos ϕ. A power factor close to unity... [Read more]

Field Test Procedure For Protective Relays

Field Test Procedure For Protective Relays

Field Test Procedure For Protective Relays 1. Relay Settings At all new protective relay installations, the relays should be adjusted in accordance with the settings given in the relay data sheets, after which, tests should be made to determine if the actual operating characteristics check with the adjustments made. The Denver Office, Facilities Engineering Branch, must be advised of field changes... [Read more]

High Voltage Substation Earth Grid Impedance Testing

High Voltage Substation Earth Grid Impedance Testing

FIGURE 1 – Voltage gradient around a substation under fault condition The purpose of this paper is to report a new test method and make a recommendation to improve the procedures according to the findings. The test method involves measurement of high voltage substations earth grid impedance, by utilization of a variable frequency current source and frequency selective measurement techniques. Safety... [Read more]

PLC-Based Monitoring Control System for Three-Phase Induction Motors Fed by PWM Inverter

PLC-Based Monitoring Control System for Three-Phase Induction Motors Fed by PWM Inverter

PLC-Based Monitoring Control System With the rapidly changes on industries and information technologies in recent years, some traditional bulk electronic appliances have to be monitored for a long time. All of their control devices such as communication interfaces gradually enter the Intemet information era. The control of all equipment has been performed through the use of computers. Most equipment... [Read more]

Hydropower In Details

Hydropower In Details

Gezhou HidroPower Dam Hydropower (from hydro meaning water) is energy that comes from the force of moving water. The fall and movement of water is part of a continuous natural cycle called the water cycle. Energy from the sun evaporates water in the earth’s oceans and rivers and draws it upward as water vapor. When the water vapor reaches the cooler air in the atmosphere, it condenses and forms clouds.... [Read more]

Benefits Of IEC 61850

Benefits Of IEC 61850

One of the significant challenges that substation engineers face is justifying substation automation investments. The positive impacts that automation has on operating costs, increased power quality, and reduced outage response are well known. But little attention is paid to how the use of a communication standard impacts the cost to build and operate the substation. Legacy communication protocols... [Read more]

Reduction In The Cost Of Electricity

Reduction In The Cost Of Electricity

Reduction In The Cost Of Electricity Good management in the consumption of reactive energy brings with it the following economic advantages. These notes are based on an actual tariff structure of a kind commonly applied in Europe, designed to encourage consumers to minimize their consumption of reactive energy. The installation of power-factor correcting capacitors on installations permits the consumer... [Read more]

The Nature Of Reactive Energy

The Nature Of Reactive Energy

The Nature Of Reactive Energy All inductive machines i.e. electromagnetic and devices that operate on AC systems convert electrical energy from the powersystem generators into mechanical work and heat. This energy is measured by kWh meters, and is referred to as active or wattful energy. In order to perform this conversion, magnetic fields have to be established in the machines, and these fields are... [Read more]

Standard IEC 60947-2

Standard IEC 60947-2

Standard IEC 60947-2 | Circuit Breakers This standard applies to circuit-breakers, the main contacts of which are intended to be connected to circuits, the rated voltage of which does not exceed 1000 VAC or 1500 VDC.; it also contains additional requirements for integrally fused circuit-breakers. It applies whatever the rated currents, the method of construction or the proposed applications of the... [Read more]

An Example Of KNX Project Design

An Example Of KNX Project Design

An Example Of KNX Project Design It is basically possible to design a residential building according to criteria similar to those of a functional building and with that to plan the same functionality. The building installations usually seen up to now have for years been based on the distribution and switching of electrical energy. This method is long outdated. Private clients still tend to derive their... [Read more]

Cost benefits of AC drives

Cost benefits of AC drives

Cost benefits of AC drives In addition to their technical advantages, AC drives also provide many cost benefits. In this chapter, these benefits are reviewed, with the costs divided into investment, installation and opera- tional costs. At the moment there are still plenty of motors sold without variable speed AC drives. This pie chart shows how many motors below 2.2 kW are sold with frequency converters,... [Read more]

Wind Power Applications

Wind Power Applications

Wind Power Applications The wind is a free, clean, and inexhaustible energy source. It has served humankind well for many centuries by propelling ships and driving wind turbines to grind grain and pump water. Denmark was the first country to use wind for generation of electricity. The Danes were using a 23-m diameter wind turbine in 1890 to generate electricity. By 1910, several hundred units with... [Read more]

ABB Feeder Protection REF615 ANSI

ABB Feeder Protection REF615 ANSI

ABB Feeder Protection REF615 ANSI The REF615 is powerful, most advanced and simplest feeder protection relay in its class, perfectly offering time and instantaneous overcurrent, negative sequence overcurrent, phase discontinuity, breaker failure and thermal overload protection. The relay also features optional high impedance fault (HIZ) and sensitive earth fault (SEF) protection for grounded and ungrounded... [Read more]

The Unique Role Of Wind Turbine Step-Up (WTSU) Transformers

The Unique Role Of Wind Turbine Step-Up (WTSU) Transformers

The Unique Role Of Wind Turbine WTSU Harnessing wind energy to perform work is not a new concept. Since the earliest of times, wind power has been captured with sails to allow traders, merchants and explorers to ply their trades and discover the world around them. On land, windmills have been used for irrigation, grinding grains, and performing crude manufacturing for centuries. Even the generation... [Read more]

Storage Systems

Storage Systems

Storage Systems | ABB Battery Energy storage technologies are of great interest to electric utilities, energy service companies, and automobile manufacturers (for electric vehicle application). The ability to store large amounts of energy would allow electric utilities to have greater flexibility in their operation because with this option the supply and demand do not have to be matched instantaneously.... [Read more]

Connecting Wind Turbines To The Power Grid

Connecting Wind Turbines To The Power Grid

Connecting wind turbines to the power grid Precautions to be taken when connecting wind turbines to the power grid: The procedure for connecting wind turbines to an electric distribution network normally consists of 2 steps: 1. First, the HV/LV transformer is energized from the high voltage side, 2. Then, in the right wind conditions and further to wind turbine adjustment tests (initial pole test,... [Read more]

Transformer Ratings

Transformer Ratings

Transformer Ratings Transformer size or capacity is most often expressed in kVA. “We require 30 kVA of power for this system” is one example, or “The facility has a 480 VAC feed rated for 112.5 kVA”. However, reliance upon only kVA rating can result insafety and performance problems when sizing transformers to feed modern electronic equipment. Use of off-the-shelf, general purpose... [Read more]

Little Known Methods to Produce More Efficient Solar Panels

Thin Film Solar While silicon is the industry common semiconductor in many electric units, which includes the photovoltaic cells that pv panels use to transform sunshine into power, it is not really the most efficient material on the market. For instance, the semiconductor gallium arsenide and associated ingredient semiconductors give nearly double the performance as silicon in solar devices, but they... [Read more]

KNX Architecture

KNX Architecture

KNX Architecture Building Control technology as provided by KNX is a specialized form of automated process control, dedicated to the needs of home and building applications. One premise for KNX is to furnish a radically decentralized, distributed approach; hence the term network. The KNX Device Network results from the formal merger of the 3 leading systems for Home and Building Automation (EIB, EHS,... [Read more]

Acti 9 – New Smarter Modular Systems

Acti 9 – New Smarter Modular Systems

Acti 9 - The Fifth Generation Of Modular Systems Acti 9 represents the fifth generation of Schneider’s low voltage modular systems. His older brother Multi 9 has finally evolved to much better and smarter system. Multi 9 was the famous and most known product of Schneider’s ex brand Merlin Gerin (now is incorporated into Schneider global brand), and now new Acti 9 is ready to inherit it. Before... [Read more]

Transformer Oil Diagnostics

Transformer Oil Diagnostics

Transformer Oil Diagnostics In addition to dissipating heat due to losses in a transformer, insulating oil provides a medium with high dielectric strength in which the coils and core are submerged. This allows the transformers to be more compact, which reduces costs. Insulating oil in good condition will withstand far more voltage across connections inside the transformer tank than will air. An arc... [Read more]

Procedure for the establishment of a new substation

Procedure for the establishment of a new substation

Procedure for the establishment of a new substation Large consumers of electricity are invariably supplied at HV. On LV systems operating at 120/208 V (3-phase 4-wires), a load of 50 kVA might be considered to be “large”, while on a 240/415 V 3-phase system a “large” consumer could have a load in excess of 100 kVA. Both systems of LV distribution are common in many parts of the world. As a... [Read more]

APC Galaxy 7000™ UPS 250-500kVA

APC Galaxy 7000™ UPS 250-500kVA

Galaxy 7000 UPS 250-500kVA by APC Three-phase Galaxy 7000, 250 to 500 kVA (up to 4 MVA in parallel configurations), includes cutting-edge technologies for high-power applications. Calling on over 40 years of experience in the Critical Power and Cooling Services division of Schneider Electric, the leader in complete, high-quality electrical power solutions, Galaxy 7000 offers optimised performance for... [Read more]

Testing performances of IEC 61850 GOOSE messages

Testing performances of IEC 61850 GOOSE messages

Testing performances of IEC 61850 GOOSE messages One of the frequent requests for relay protection devices is support for the IEC 61850 standard. As part of the standard special messages are also planned for a quick exchange of information between the IEDs – so called  GOOSE (Generic Object-Oriented SubStation Event). These are mainly trip, interlocking, breaker failure and similar signals.... [Read more]

GE AKD-20 Low-Voltage Switchgear

GE AKD-20 Low-Voltage Switchgear

AKD-20 low-voltage switchgear continues the tradition of the AKD switchgear line while delivering enhanced arc flash protection. Built to ANSI standards, its protection features include non-vented panels plus insulated and isolated bus, and it integrates our new state-of-the-art EntelliGuard® breaker-trip unit system. It also features an optimized footprint so that it now fits into a smaller area... [Read more]

Maintenance Of SF6 Gas Circuit Breakers

Maintenance Of SF6 Gas Circuit Breakers

Maintenance Of SF6 Gas Circuit Breakers Sulfur Hexafluoride (SF6) is an excellent gaseous dielectric for high voltage power applications. It has been used extensively in high voltage circuit breakers and other switchgears employed by the power industry. Applications for SF6 include gas insulated transmission lines and’gas insulated power distributions. The combined electrical, physical, chemical... [Read more]

Wind Power Storage

Wind Power Storage

Wind power storage development is essential for renewable energy technologies to become economically feasible. There are many different ways in which one can store electrical energy, the following outlines the various media used to store grid-ready energy produced by wind turbines. For more on applications of these wind storage technologies, read Solving the use-it-or-lose-it wind energy problem Electrochemical... [Read more]

Bus Joint Fundamentals

Bus Joint Fundamentals

Siemens TechTopic | Bus Joint Fundamentals Proper design of bus bar joints is a necessity for long equipment life. The objectives that a good bolted bus bar joint must fulfill include: • It must provide good conductivity, so that the bus system will meet the temperature rise requirements in the ANSI standards. • It must withstand thermal cycling, so that the low resistance joint will be maintained... [Read more]

Paralleling Three-Phase Transformers

Paralleling Three-Phase Transformers

Paralleling Three-Phase Transformers Two or more three-phase transformers, or two or more banks made up of three single-phase units, can be connected in parallel for additional capacity. In addition to requirements listed above for single-phase transformers, phase angular displacements (phase rotation) between high and low voltages must be the same for both. The requirement for identical angular displacement... [Read more]

Guide To Low Voltage Busbar Trunking Systems (1)

Guide To Low Voltage Busbar Trunking Systems (1)

Guide To Low Voltage Busbar Trunking Systems Modern electrical desdign and installations are often placing increasing demands on all products of the electrical equipment manufacturer. Products must have: • Reliable service life • Adaptability to new requirements • Low installation costs • Low maintenance costs • Inherent safety features • Minimal purchase cost • Energy efficiency . In... [Read more]

ANSI/IEC Relay Symbols

ANSI/IEC Relay Symbols

There are two methods for indicating protection relay functions in common use. One is given in ANSI Standard C37-2, and uses a numbering system for various functions. The functions are supplemented by letters where amplification of the function is required. The other is given in IEC 60617, and uses graphical symbols. To assist the Protection Engineer in converting from one system to the other, a select... [Read more]

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