Saturday, December 24, 2011

8-Spring-Elongation-due-to-Electric-Field-Attraction-Equivalent-Capacitance-IIT-JEE-Phy.flv

!: 8-Spring-Elongation-due-to-Electric-Field-Attraction-Equivalent-Capacitance-IIT-JEE-Phy.flv

Hi Please inform your friends that Prof. Subhashish has reorganised, added, and indexed the IIT-JEE study videos. He is making the full Physics and Math course available for FREE at zookeepersblog.wordpress.com Enjoy and learn. You can download the lectures as well.

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Saturday, December 17, 2011

6-CET(J&K)-2001-RPET-UPSEAT-2002-JEE(Orissa)-2003-Magnetic-Field-at-Centre-of-Loop-Phy.flv

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Sunday, December 11, 2011

!: SouthEast2

power transformers, step-down transformers, distribution transformers, autotransformers, buy-sell transformers, electrical transformers, rebuilt transformers, substation transformers, generator step-up transformers, furnace transformers

SouthEast2

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Tuesday, November 29, 2011

Transformers Ultimate Bumblebee

!: Discount Transformers Ultimate Bumblebee clearance sale

Brand : Transformers
Rate :

Price : $99.99
Post Date : Nov 29, 2011 08:45:51
Usually ships in 1-2 business days

BUMBLEBEE stayed on Earth after the destruction of the AllSpark to continue protecting his friend Sam, and he has stayed with the young human every day since. As more DECEPTICONS have appeared to threaten Earth, the friendship between boy and robot has become something more. Now, human and AUTOBOT are teammates in a battle for the fate of the world, and neither will rest until every last DECEPTICON is a smoking wreck. The biggest robot star in the world is back! BUMBLEBEE is ready to roll into action against the DECEPTICONS with motion-activated lights and sounds. His robot and vehicle modes have been updated with the latest in movie-accurate detail, making this awesome robot cooler than ever! In robot mode, this friendly figure features light-up eyes and a flip-down battle mask to let the enemy know he means business! Animatronic arms, head and wings bring this awesome ally to life and ready for battle. With a cannon that automatically aims and fires, this trusty teammate will help you recreate exciting film scenes or stage new battles of your own. Convert the figure to a cool Camaro concept car in vehicle mode and roll out! With updated hood and grille detail, this guy certainly is a looker! Headlights and taillights complete his look, while revving engine sounds, horn and car alarm and even screeching brakes and crashing sounds let you know this sleek sidekick is on the move! The battle is on are you ready?

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Wednesday, November 23, 2011

Amtronics Step Up or Down Transformer 5000 Watt

!: Good bargain Amtronics Step Up or Down Transformer 5000 Watt compare

Brand : Amtronics | Rate :

| Price :
Post Date : Nov 23, 2011 10:18:26 | Usually ships in 1-2 business days

Amtronics Step Up or Down Transformer 5000 WattInput/Output:110V AC to 220 VAC (Step Up) or 220V AC to 110VAC (Step Down); Connectors: Grounded European "Schuko"Plug on Cord; Two Grounded American Sockets on Transformer.Dimensions:12"x10"x9; Weight: 22 kg - 48.4 lb.

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Saturday, November 19, 2011

Power Bright VC1500W Voltage Transformer 1500 Watt Step Up/Down 110 Volt - 220 Volt

!: Purchase Power Bright VC1500W Voltage Transformer 1500 Watt Step Up/Down 110 Volt - 220 Volt purchase

Brand : Power Bright
Rate :

Price : $74.39
Post Date : Nov 20, 2011 02:21:05
Usually ships in 24 hours

This is a voltage converter or transformer that can be used as a step up transformer in 110/120 volt countries or as a step down transformer in 220/230/240 volt countries. This heavy duty voltage transformer can be used for continuous duty. It will convert voltages of 220-240 volts to 110-120 and will also convert voltages from 110-120 to 220-240 volts.

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Monday, November 14, 2011

LiteFuze convertingbox 2000 Watt Light Weight Premium Voltage Converter Transformer - Step Up/Down - Lifetime Warranty Full Grounded Cord (Free Euro Plug) 110/120 - 220/240 Volts - No Noise - Circuit Breaker Protection

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Brand : LiteFuze | Rate :

| Price :
Post Date : Nov 15, 2011 00:04:23 | N/A

Key Features: * Up to 2000 Watt continuous use capacity * Step Up/Down Functionality: o Step Down: Converts Single Phase 220/230/240-volt Electricity to 110/120-volt o Step Up: Converts 110/120-volt Electricity to Single Phase 220/230/240-volt * 3 x US Patented Universal Output Socket - accepts virtually any plug from around the world. * convertingboxTM Noise reduction technology * convertingboxTM half-weight technology * *Efficiency Factor: 1.25 * Dynamic casing design offers ventilation to the voltage transformer * Fully Grounded Transformer from Input to Output for safe operation * CE Certified * Lifetime Warranty * Circuit Breaker Protected - no need to replace fuses * Free Euro Plug AdapterSpecifications: * Weight: 14 lbs * Size: 9.25" x 8.25" x 6.25"*Efficiency FactorUse this factor to calculate the correct wattage transformer needed for your items. Multiply the WATT rating on your product with this factor and purchase transformer of at least that size.Example:If your blender requires 350W, then multiply 350 x 1.25 (efficiency factor of convertingboxTM) = 437.5W. Thus, convertingbox 500 is recommended for this particular blender. To use multiple products, simply add watt rating of each product and multiply the combined watt rating with the efficiency factor. Always purchase a larger transformer than your appliances required wattage to handle any power surges during operation. Feel free to contact or call us if you have any questions.

2000 Watt Capacity for Continuous Use
Heavy Duty Step Up/Down Voltage Converter
Fully Grounded Transformer from Input to Output for safe operation
Lifetime Warranty, Circuit Breaker Protected, CE Certified, No Noise
Weight: 14 lbs Size: 9.25" x 8.25" x 6.25"

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Monday, November 7, 2011

Jotting it Down With a Digital Writing Pad

!: Jotting it Down With a Digital Writing Pad

What with all the technology we have, sometimes, all we have to do to get everything done is to sit in front of the computer for hours, press several letter keys, click and drag the mouse, and the work is finished. But sometimes, nothing compares to just writing it down on a notepad or a piece of paper with a pencil or a your favorite pen. The problem with this method is that these documents can easily be damaged or destroyed, when spilled with water, crumpled, or worse, torn apart. But technology has, once again, come up with a way to store everything you write down with a digital writing pad.

A digital writing pad is a device that generally does not need to be connected to a computer for it to operate. Just like the ordinary notepad or a clipboard, you can write and draw anything and everything you need and want, and the digital pad automatically stores it for you with its built-in memory. Then, if you want to review what you have just written or drawn, you can connect it to the computer to take a look at it. Generally, what you can do with a digital pad is that you can clip on just about any ordinary piece of paper, and write everything down using a digital inking pen. The pad stores everything down as you write it. Usually, one page you use will equal a one page as well in a digital document. You can even select what file type you want to save it in, making your own e-book for more convenience.

With these device, not only will you have a back-up soft copy in the form of a digital file saved in your digital pad, you also have a hard copy with you in paper. A digital writing pad can benefit a wide range of people. For artists who prefer a more traditional medium in a pen and paper but want their artwork in safekeeping, having one of these digital pads can be very helpful. Architects, interior designers who have to sketch in a lot of details in their blueprints and interior structure will also have an easier time by having a digital writing pad. Even doctors and hospitals can make use of a digital writing pad, making every document saved, filed, and organized for future references. For anybody whose job requires them to be on the move, a digital pad is a handy device to bring with them. It is very lightweight - as it is very much like an ordinary office clipboard - and very thin, making it fit in your hand-carry or your attaché case.

As it is an easier, more convenient, and safer alternative as compared to bringing a lot of paper to your workplace, it will not be a surprise if a digital writing pad will replace the use of notebooks in the long run.

Jotting it Down With a Digital Writing Pad

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Wednesday, November 2, 2011

SM 2000J - JAPAN 100V TO 110V / 120V JAPANESE TO AMERICAN STEP UP/DOWN TRANSFORMER- 2000 WATTS

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Rate :

| Price : | Post Date : Nov 03, 2011 03:03:04
Usually ships in 1-2 business days

This transformer is capable of both Up/Down Voltage Conversion for Japan and the USA. Maximum Capacity: 2000 Watts On/Off Switch Converts 100V to 120V & 120V to 100V Fuse Protected.Transformer Purchase Guide:Remember to leave at least a 60%-70% slack for the transformer. For the TVs, the power surge margin is 5 times the wattage of the TV. Heating appliances, laser printers and power tools spike when you turn them on. For these products you need to buy a transformer that is at least 3 times the items capacity.

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Monday, October 31, 2011

LiteFuze LR-3000 3000 Watt Heavy Duty Voltage Regulator w/ Voltage Converter Transformer - Step Up/Down 110/120/220/240V (Free Euro Plug) - Patented Universal Output Sockets

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Brand : LiteFuze | Rate :

| Price :
Post Date : Oct 31, 2011 20:45:34 | Usually ships in 1-2 business days

Up to 3000 Watt Maximum Capacity Heavy-Duty Voltage Regulator Heavy duty for continuous use On/Off Power Switch LED Indicator for Power Source Single phase Dual Voltage Step Up or Step Down functionality Input: 110V/120V or 220V/230V/240V (Single Phase) Output 110V/120V or 220V/230V/240V (Single Phase) Input Selection in the rear of the converter Dimensions: 11.5"x10.25"x5.5" * Weight: 27 lbs. Four outlets for output in the front - 2 sockets - Universal outlet (220/240v single phase) - 2 sockets - Grounded USA (110/120v) Fuse protected with Built in Circuit Breaker NOTE: We recommend to use a Voltage Converter / Transformer that's max watts is at least 50% higher than your appliance. Some appliances such as Power tools, Motors, Laser printers and TVs require 2-3 times more watts at start up than the printed rating. We do not recommend voltage converters to use with coffee makers, hair dryers, microwave ovens and other heat producing appliances. US 220V products are two-phase 220V products and are not designed for use with this item.

Heavy Duty Voltage Regulator with Voltage Transformer
Step Up/Down Voltage Transformer Functionality
Full Grounded USA Cord with a Free Euro Plug
Patented Universal 220V Output Socket - It will accept virtually any plug from around the world.
Built-in Circuit Breaker

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Thursday, October 27, 2011

Running to Burn Fat - Step Up Your Heart Rate

!: Running to Burn Fat - Step Up Your Heart Rate

While there is nothing essentially wrong with running to burn fat, it is a good idea to consult with your doctor before you start pounding the pavements. Your doctor can tell if you are fit enough to run or if there is any other reason you should not. If you are engaging in any physical activity after a long hiatus or you are already next door to obesity, you would need to start out slowly and work your way up over the course of several weeks. Running can be very hard on the joints and every extra pound of weight can put that much more pressure on your joints. Running to burn fat can wait; walk it for a while and increase your pace with time.

If you already jog regularly and are thinking of now running to burn fat, then all you need to do is start running. Run for a few minutes, then go back to your regular jogging pace and repeat several times during your workout. Increase the length of time that you run every few days until you are jogging only to warm up and cool down.

If you do not normally exercise, starting out by running is out of the question. You must work up to it. Start by taking brisk walks every day, then move up to power walking, then jogging and finally - running. Each phase should be done the same way described above. Increase your speed for a while, then drop down to your typical brisk pace and repeat. Do this until you are running through your workout.

Take off running to burn fat and don't look back! The svelte you is just around the corner.

Running to Burn Fat - Step Up Your Heart Rate

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Monday, October 24, 2011

Goldsource® STU-1000 Step Up/Down Voltage Transformer Converter - AC 110/220 V - 1000 Watt

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Brand : Goldsource | Rate :

| Price : $60.85
Post Date : Oct 25, 2011 04:30:58 | Usually ships in 24 hours

Goldsource® STU-1000 Step Up/Down Voltage Transformer Converter - AC 110/220 V - 1000 Watt

Made by one of the leading manufacturers in the industry, the Goldsource STU series step up/down voltage transformers offer you a safe, reliable, affordable & convenient solution to converting voltages from 110-120 volts up to 220-240 volts or from 220-240 volts down to 110-120 volts for both home use & industrial applications.

The STU-1000 is rated at 1,000 watts maximum. It features a heavy-duty cord with a standard US 3-prong plug plus a free American to German outlet plug adapter. There are a total of three outputs on the front panel. Two are grounded outputs, one designated for 120 volts with a US standard outlet, the other for 220 volts only with a universal outlet. The last one is a 5V standard USB jack, a unique feature of the STU series & 1st in the industry. And most importantly, all three outputs can be used simultaneously & continuously.

For safety, it's recommended by the manufacturer that the voltage transformer's maximum power should be equal or greater than the power rating of your appliance multiplied by 1.5. For example, if you have an appliance rated at 100 watts, you will need to pick a transformer with a maximum power of 150 watts or greater.

More Specification..!!

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Monday, April 11, 2011

Setting Up A Wireless Router

!: Setting Up A Wireless Router

Using a wireless router makes computing life much more enjoyable. Why confine yourself to work on the Computer in the same location you took it out of the box? Setting up a wireless router is easy and allows you the freedom to access the Internet, files, Printers, plus much more, from virtually any location in your house or yard. Before you shake your head about setting up a wireless router on your own, trust me, if I can do it, whatever can.

Here are some easy steps for setting up your wireless router.

Select the exact wireless router for your needs.

If you walk into your nearest Best Buy or other Computer store, you will see they have a wide range of routers available. There are basically (3) wireless networking technologies on the store today; 802.11a, 802.11b, and 801.22g. So what are the differences in the middle of these wireless technologies?

802.11a wireless protocol is the oldest version of wireless networking technologies currently available. While you may find 802.11a wireless hardware at discounted prices, I would strongly urge you to avoid them. 802.11a is small in range and capacity versus 802.11b and 802.11g. So why set up your first wireless network with the oldest technology.

802.11b wireless protocol (11Mbs) is by far the most tasteless wireless technology in use today. If you adopt this wireless protocol, you will be fine. But why not start with the latest and greatest wireless protocol currently available?

802.11g is the best wireless technology on the store and all new Computers with built-in wireless cards apply this protocol. 802.11b wireless protocol was superceded by backwards compatible 802.11g (54Mbs). What this means is that if you have an 802.11b card on some of your computing devices, you can use an 802.11g wireless router without the need to replace your wireless card. If you have the option, I would strongly propose purchasing 802.11g cards for your computers as well to get the maximum benefits of this wireless network technology.

Connecting your wireless router

Before starting, be sure you have a paper copy of all instructions or the router by hand in front of you. Sounds simple, I know, but you would be surprised how many citizen neglect this basic step. Ok, let's get started!

The first step will be to power down your Dsl or cable modem. This will be done by unplugging the devices from the electrical outlets.

Next, join together the wireless router to your modem. I would propose retention the length in the middle of the router and modem as close as possible. I have both modem and wireless router setting side by side on my desk.

Included with the wireless router, you should have a short cable. This is your network cable. Plug the network cable into the wireless router in the port labeled Internet, Wan Or Wlan. This designation varies depending on the brand of wireless router you purchased. It does not matter which end of the network cable you join together to the router, since the same type of connector is used on both ends.

Once you have linked the network cable to your wireless router, join together the other end of the cable into your modem. Your modem will only have one port available. You will hear a "click" when a acquire relationship has been established.

You can now re-insert the cable which provides your Internet access back into your Dsl or cable modem.

At this point, you will want to power up your modem. The modem should all the time be powered up first. Allow a few moments for the Internet relationship to synchronize with the modem.

It is now time to configure your wireless router. Temporarily disconnect the network cable from the router and modem. Once you have completed this, join together the network cable to any port on the wireless router not labeled as Internet, Wan Or Wlan. You will probably have at least 4 open ports; any one will do. Next, join together the other end of the network cable to your computer. This may seem confusing, however, you need a direct relationship in the middle of the router and computer to permit configuration.

On your computer, open up an Internet browser and enter the address which corresponds to your exact make of wireless router.

Router Address Username Password

3Com 192.168.1.1 admin admin

D-Link 192.168.0.1 admin

Linksys 192.168.1.1 admin admin

Microsoft Broadband 192.168.2.1 admin admin

Netgear 192.168.0.1 admin password

Once you have entered the address into your browser, you will be prompted to enter a username and password. Reference the chart for your respective information. While in the configuration mode, you will have the selection to turn your password, which I strongly suggest.

Next, you will need to set your network id or Ssid. This name does not have to be lengthy, but choose something that is unique and but easy enough for you to remember.

Protecting your network. You will also have the selection to either acquire your network or leave it "open". By leaving your network "open", whatever within range of your wireless router signal will be able to access your network. If you live in a location in a improvement or apartment, there is a good occasion man will be riding your network..using your Internet access for free and degrading your access quality. It is a good rule of thumb to acquire access to networks and computers whenever possible.

To acquire your network, adopt the Wep tab or option. Wep stands for Wireless Encryption. You will be prompted to enter a password or passphrase. We have already addressed changing your administrator password from the default, so let's move on. Be sure to adopt Apply or Ok after making your selections.

Disconnect the network cable from your computer, and reconnect as before. One end of the network cable goes into the port on the wireless router marked Internet, Wan, or Wlan, and the other end connects to your Dsl or cable modem.

After a few brief moments, an icon should appear on your desktop alerting you a wireless network has been detected. Right click on the icon and adopt "View available Wireless Networks".

If you do not see your network, click on the Refresh button from the menu. Once your network is visible, click on it.

If you have Wep protected your wireless network, you will be prompted to enter your password or passphrase. If you have chosen to leave your network unprotected, you will be cautioned that you are attempting to access an unsecured network. adopt your network and press "Connect".

Article written by Lsg at Lilsurfergirl.com [http://lilsurfergirl.com/2007/11/08/choosing-the-right-laptop/]

Setting Up A Wireless Router

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Thursday, March 31, 2011

Transformer manufacturer

!: Transformer manufacturer

Transformer manufactures are fellowships that invent and contribute power distribution transformers. This may consist of extremely efficient amorphous metal core transformers, box substations, battery chargers, switchgear and connected electrical equipment.

Many of these fellowships will assess any definite personel power requirements and aim to contribute cost efficient and reliable power solutions that work for the buyer and the environment. The equipment they contribute can be new man-made gear or re-engineered gear and will come with prominent manufactures guarantees.

There are many dissimilar types of transformers which are used for a wide range of applications, and some of these are:

o Super low amorphous transformers

o Substations

o Switchgear

o Battery chargers

o Voltage optimisation

o Toroidal transformers

o Step up / Step down transformers

o Tool and Site transformers

Step up & step down auto transformers are small in size and weight and can be legitimately installed into existing equipment or supplied in an enclosure with or without plug, cord and receptacle.

Tool and site transformers are used for power tools, machinery and lighting applications on construction sites; housed in reinforced fibreglass they contribute endurance and security. Tool and site transformers are normally 110v, 230v, and 415v and all conform to the strictest security standards.

For outdoor use waterproof transformers are important and will commonly have an input of 230v and an yield of 12v to 24v. These types of transformers are commonly used for outdoor lighting and powering organery pond pumps.

Transformers are devices that change electrical power from one circuit to someone else circuit. This is achieved by passing the electricity straight through the transformers coils; these coils are referred to as inductively coupled inductors. Most transformers have the coils wound colse to a ferromagnetic core.

Transformers can be man-made in a wide range of sizes. They can be small adequate to fit into a microphone, or they may be extremely large units that weigh hundreds of tons and used to interconnect national power grids.

Although the range of designs and sizes may vary enormously, they all work by the same basic principles.

Transformer manufacturer

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Tuesday, March 22, 2011

Are Wind Turbine Step-Up Transformers the Weak Link in the Wind power supply Chain?

!: Are Wind Turbine Step-Up Transformers the Weak Link in the Wind power supply Chain?

In the rush to cash-in on wind energy, developers are often trading low first costs for higher total costs of possession to be shouldered later by the wind farm owners and operators.

Converting wind power to electrical power is the fastest growing segment of the Us power sector. Today, wind power represents less than 5% of the Us electrical generation and is targeted to reach 20% in the foreseeable future. For this to happen, new sites need to be industrialized in spite of a down turning economy.

Bolstered by ready federal stimulus dollars, we are seeing a virtual modern day 'land-rush'. In the words of one commerce leader, 'if there is a site that has a viable wind profile, entrance to network connections, and entrance for delivery of materials, and we don't manufacture it, some one else will.'

This head long rush to setup more and more wind turbines has outstripped the usual developmental studying curve, where new technologies mature by a process of trial and error, resulting in defining equipment remarkable for the job at hand.

The added economic pressure of today's market has made an already competing market even more demanding. This has, in the view of many commerce insiders, resulted in purchasing decisions for equipment based largely on the lowest introductory cost solutions and not solutions that will contribute the best choice in terms of total cost of ownership, network stability, less down time and lost revenue from high maintenance issues. This is nowhere as apparent as in the Case of Wind Turbine Generator (Wtg) transformers.

Historically this Wtg transformer function has been handled by conventional, 'off the shelf' distribution transformers, but the relatively large numbers of new failures would strongly advise that Wtg transformer designs need to be made substantially more robust. The institution of using approved 'off the shelf' distribution transformers as a low cost solution is folly. In some Cases site operators are maintaining a quantity of spare transformers to combat the frequent outages caused by proper distribution transformers being used where they are not suitable.

The role of the Wind Turbine Generator (Wtg) transformer in this process is primary and, as such, its manufacture needs to be carefully and thoughtfully analyzed and reevaluated.

Transformer Loading:

Wind turbine yield voltages range from 480 volts to 690 volts. The turbine yield is transformed, by the Wtg transformer, to a collector voltage of 13,800 to 46,000 volts. The turbines are highly dependant upon local climatic conditions; and this can succeed in yearly midpoint load factors as low as 35%. The relatively light loading of Wtg transformer has a favorable succeed on insulation life but introduces two unique and functionally primary problems.

The first problem is when lightly loaded or idle, the core losses come to be a more primary economic factor while the coil or winding losses come to be less significant. Typically used price estimation method do not apply to this scenario. Nema Tp1 and Doe efficiencies are not modeled for the operational scenario where midpoint loading is near 30-35% and, consequently, should be cautiously applied when calculating the total cost of possession for Wtg transformers.

The second problem is that the Wtg transformer is subjected to frequent thermal cycling as a function of varying turbine loads. This causes repeated thermal stress on the winding, clamping structure, seals and gaskets. Repeated thermal cycling causes nitrogen gas to be absorbed into the hot oil and then released as the oil cools, forming bubbles within the oil which can migrate into the insulation and windings to create hot spots and partial discharges which can damage insulation. The thermal cycling can also cause accelerated aging of internal and external electrical connections.

Harmonics and Non-Sinusoidal loads:

Wtg transformers are switched with solid state controls to limit the inrush currents. While potentially aiding in the introductory energization, these same electronic controls contribute damaging harmonic voltages that, when coupled with the non-sinusoidal wave forms from the turbines, cannot be ignored from a heating point of view. When a rectifier/chopper law is used, the Wtg transformer must be designed for harmonics similar to rectifier transformers, taking the supplementary loading into consideration as well as providing electrostatic shields to preclude the replacement of harmonic frequencies between the former and secondary windings.

Transformer sizing and voltage variation:

Wtg transformers are designed such that the voltage is matched to the wind turbine's yield voltage exactly. There is no 'designed in' over-voltage capacity to overcome voltage fluctuations which are a frequent problem with wind turbines. At the same time, the generator yield current is Monitored at millisecond intervals and the operational limits allow up to 5% over-current for 10 seconds before it is taken off the system. Therefore, the Wtg transformer is designed to match the generator yield with no overload sizing, and the Wtg transformer manufacture must be uniquely robust to function without it

Requirement to withstand Fault Currents:

Typically, approved distribution transformers, power transformers, and other types of step-up transformers will 'drop out' when subjected to a fault. Once the fault has cleared, the distribution transformer is brought back on-line. Wind turbine generators, on the other hand, in order to enounce network stability are not allowed to disconnect from the law due to network disturbances except within certain guidelines industrialized for generating plants. The length of time the generator is required to stay on line can vary. During this time the generator will continue to deliver an abnormally low voltage to the Wtg transformer. Therefore, During faults, the transformer may be required to carry as low as 15% rated voltage for a few cycles and then ramp back up to full volts a few seconds after fault clearing. The Wtg transformer must be uniquely designed with enough 'ruggedness' to withstand full short circuit current During the introductory few cycles when the maximum mechanical forces are exerted upon the Wtg transformer windings.

Conclusions:

The role of Wtg transformers in today's wind generation task is unique; it's manufacture must be equally unique and robust. Don't trade long term reliability and lower total cost of possession for low introductory cost.