Posts Tagged ‘electromagnetic induction’
July 22nd, 2009 | 
Author: Electricity or power has become the major part of our daily life and without electricity we cannot imagine a life today. Most of our household appliances work on electric current. We face various power problems due to voltage fluctuations. Sometimes our home appliances malfunction due to voltage problems. The solution for all these problems can be rectified only through a transformer. Power transformers or a transformer is an electrical device that is used to change an alternating current voltage from one electric circuit to another through electromagnetic induction. These transformers are employed in various mechanisms to reduce the incoming voltage or increasing the voltage of electrical equipments. These transformers have two or more windings wounded on a laminated iron core and the number of windings is based on the requirement of electric voltage that the transformer is used to supply.
There are many types of transformers like isolation transformer, power transformers, electrical transformer, audio transformer, current transformer, high voltage and low voltage transformers, step-up and step-down transformers etc. Each of these kinds has their own properties and usages in transferring voltage based on the appliance it is attached with.
Electric transformer is a device that is employed in increasing or lowering the voltage of alternating current or voltage. Electric transformers have two sets of coils called primary and secondary coils linked around magnetic fields that work as conductors. This number of windings determines the workability of the transformer. There are various forms of electrical transformers like step up transformers to raise voltage or step-down transformer to lower voltage levels that can be used in power lines or household appliances to regulate current supply and reduce electricity bill costs.
Current transformers are used to get secondary or additional current to produce current from the transformer and this helps the customers to get ample current for their various applications like metering and protective relaying in electrical power industry to get safe measurement of large currents even from high voltages. Audio transformers are designed with epoxy resin that facilitates improvements in sound qualities by removing disturbing audio signals that is sourced from other devices. Flyback transformers can convert the input voltage and current to the expected output voltage and current and these transformers are available in variety of models and sizes.
Electrical switches are the electrical components that are used to stop the electricity flow by interrupting the current or diverting it from one conductor to another. These electrical switches are available for medium current, low current and high current appliances. Circuit breaker is an electrical switch that operates automatically to cut off or break a circuit from causing damage due to high voltage. This is vitally employed in detecting the fault in the circuit mechanism and cut the electrical flow to avoid repair of the appliance. These circuit breakers are of different types like vacuum circuit breakers, SF6 circuit breakers, fixes mounted circuit breakers, etc.
There are various tips that we have to consider in selecting the best transformer from the most excellent companies to enjoy trouble free and secured electrical services. The greater protection of these power transformers can be confirmed if they own the TVSS surge protection. The surge protectors are devices that guarantee safety of electrical appliances from voltage spikes by regulating the current that is supplied to the appliance. The voltage is maintained either by obstructing or reducing the ground voltages to a safer measure. Most of the power transformers that are available today have built-in surge protection to offer high quality devices to the customers.
The most significant thing that we must remember is though the electricity is much important to us we must be very careful in handling power transformers as any of misusage can kill anyone.
PowerReps is a manufacturer representative for power transformers and TVSS surge protection companies.
Article Source: Importance Of Power Transformers
Today power cuts have become quite common and frequent and more often we experience power breakups and power failure. In this condition UPS will not be able to provide backups for long period as it can provide power back-up only for a limited time period. To overcome this problem generators are used that provide continuous power as long as the fuel supply is available. Generator is quite useful in many institutions, offices and factories where continuous power supply is a must. Generators produce electricity by converting mechanical energy to electrical energy with the help of the fuel used in the generators. The mechanical energy of the fuel undergoes electromagnetic induction and they turn into electrical energy using motor of the generator.
Generators are considered as the reliable source of power that can be used in both home and offices. Generators are very useful and its effectiveness is regularly felt when there is sudden power cut and especially when power cuts occur at the most crucial time. Generators are available in different model and depending on the requirements one can buy generators. Generally generators are divided into two broad categories of domestic generators and industrial generators which are used in heavy industries. Generators have become a common necessity product that is a must for every offices, industries, hospitals, and even homes. Everywhere a generator is a must and according to the specific requirement a generator is chosen to provide continuous power supply if there is a sudden break in the main power. It works by converting mechanical energy to electrical energy with the help of the fuel used in the generators.
Generator power output is measured in watts therefore before buying a generator one should decide the required size of the generator that will meet his requirements. For domestic purposes a portable generator with a 2000 watt generator will be sufficient but for the meeting the industrial power requirements a generator with higher output will be required. Some of the highlighting features of generators that play important role while deciding on the generators are:
• Spark arrester- Spark arrester is a must in generators if the generators have to be used near combustible materials.
• Valves- Large generators have valves mounted overhead that makes generators long lasting and more reliable.
• Pull Start- Generators having the facility of pull start helps to easily start the generators.
• Auto Shutdown- In case of low fuel condition an automatic shutdown switch is provided to prevent accidental damage.
Generators are really a boon especially in the field where continuous power supply is a must, like in the hospital field where certain medical devices required continuous power for saving the life of the patients. Similarly in many industries machineries are continuous running and even power break down of few minutes can result in severe losses, so here also generators prove to be quite efficient for continuous running of the machineries. Generators are little bit expensive but keeping in mind its utility it is found to be worth.
Datapowerprotection.co.uk provides a range of Generators, power protection systems and UPS accessories. It is the best place for Diesel Generators and emergency standby generators which give power supply continuously.
Article Source: Generators: Providing Relief from Power Cuts
The phenomenon of electromagnetic induction was first discovered by Michael Faraday in 1831, and it is evident that he realised at least a part of its future potential in the modern world. A contemporary politician asked him about the usefulness of the discovery; he answered ‘at present I do not know, but one day you will be able to put a tax on it.’
The earliest record of using electromagnetic technology to locate buried cables dates from around 1910. More portable locators were made over the next years and the Sharman Main Finder was just one example. The user instructions give a tinge of envy to anyone trying to trace gas pipes .. ..’just clip the generator to a gas bracket in the nearest house or onto a street lamp.’
American and German schools of design emerged during the years leading up to the Second World War. In North America roads were wide and wide cables hung on poles so the main requirement for a locator was to locate widely spaced buried pipes. The result was a simple, high frequency, low power and low cost locator.
In Germany, cables as well as pipes were buried under narrow streets, so elaborate low frequency and high power locators were developed that required considerable expertise to obtain satisfactory results.
Dr Gerhard Fisher of California designed the Metallascope, the first high performance buried pipe and cable locating set. His system made use of the latest scientific developments and his company exists today and still produces the M-scope, an up-to-date descendent of the original Metallascope.
One of the engineering sections of Bell Laboratories studied the problem of accurate location of newly buried cables and recognised that an antenna with twin sensing aerials would give more positive plan definition, and also measure the depth of a target cable. The subsequent design, called the Depthometer, was engineered and manufactured in 1964. It was another 12 years before the first commercial twin aerial antenna locator was made by the Electrolocation company in Bristol England.
The twin aerial system was found to have substantial advantages over single aerial locators. Twin sensing aerials combined the seemingly contradictory qualities of discrimination with sensitivity. For the first time it was possible to locate buried cables below an overhead power line and to sort out crowded utility services under a city street intersection.
The introduction of the twin aerial antenna coupled with miniaturised electronic circuitry coincided with a programme of extending and upgrading utility distribution systems. This growing demand and technical progress resulted in a series of advances and new features to make locating more certain and more simple. Some of these advances included:
” Combination of active and passive signal reception
” Multi-frequency locating sets enabling the user to select the most suitable frequency for each application
” Electronic depth measurement.
” Current measurement along the length of a pipe or cable to detect coating or insulation defects.
” Current direction recognition to verify the identity of a target line.
” Permanently installed signal transmitters to apply a signal tone to a telephone cable over distances up to 150km/100 miles.
Today, electromagnetic locators are the worldwide standard for locating buried pipes and cables. A number of specialised manufacturers offer a choice of locators ranging from simple equipment used to detect the presence of buried cables to sophisticated instruments for pinpointing, identifying and fault finding buried pipes and cables in the most complex situations.
Written by Select Surveys, one of the UK’s leading independent surveying companies specialising in using electromagnetic, CAT and ground penetrating radar equipment to detect underground cables and utilities.
Article Source: A History of Underground Electromagnetic Surveying