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    GPS
    December 8, 1993 - U.S.A.

    The U.S. Secretary of Defense declared that the Global Positioning System, accurate within 100 meters, had 24 GPS satellites operating in their assigned orbits, available for navigation use at Standard Positioning Service (SPS) levels for civil users. This Initial Operational Capability was followed on 27 Apr 1995 with a formal declaration by the U.S. Air Force Space Command that the GPS satellite constellation had met the requirement for Full Operational Capability after successful testing for military functionality. This worldwide, satellite-based radionavigation system used as the DoD's primary radionavigation system provided authorized users encrypted Precise Positioning Service accurate to at least 22 meters.

    THE REPARATION OF ROYALTIES TO NATIVE AMERICANS
    December 8, 2009 - United States

    The Obama administration has announced that it would pay Native Americans $3.4 billion to settle a class-action lawsuit that claims the federal government cheated them for more than a century of royalties for oil, mineral and other leases. This settlement will be ending a thirteen-year legal battle that has led to 3,600 filings, millions of pages of discovery documents and eleven separate appellate decisions. It is the largest settlement Native Americans have ever received from the federal government, and eclipses the sum of all previous settlements. The dispute stems from a 19th century decision to grant parcels of land to individual Indians and place the properties in trust accounts.

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    by Earth Day, Kenya

    "...All of us have a God in us, and that God is the spirit that unites all life, everything that is on this planet. It must be this voice that is telling me to do something, and I am sure it'as the same voice that is speaking to everybody on this planet at least everybody who seems to be concerned about the fate of the world, the fate of this planet. Wangari Maathai-Noble Peace prize winner, Deputy Minister of Environment, founder Green Belt movement in Kenya...."
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    "...Our greatest happiness does not depend on the condition of life in which chance has placed us, but is always the result of a good conscience, good health, occupation, and freedom in all just pursuits...."

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    Steve Jobs' annual salary was $1, just enough to keep company health benefits. Cancer Facts & Figures
    about Besides Lung Cancer

    Besides lung cancer, tobacco use also increases the risk for cancers of the mouth, lips, nasal cavity (nose) and sinuses, larynx (voice box), pharynx (throat), esophagus (swallowing tube), stomach, pancreas, kidney, bladder, uterus, cervix, colon/rectum, ovary (mucinous), and acute myeloid leukemia.

Types Of Switchgear :

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ARTICLE INFORMATION :

Switchboards are used in many electronic applications. Do you know what switchgear is? What do small companies use to direct power where it is needed? Large power plants use switchboards to distribution power.

ARTICLE CONTENT :

There are two systems or panels that are used to redistribute power or electric current to other equipment or circuits. One is the switchboard and the other is switchgear.

Electric switchboards are a device that directs the electricity from one source to another. It is composed of an assembly of panels. Each panel contains switches to allow electricity to be redirected.

With a switchboard, a technician is protected from possible electrocution. The switches in the board control the amount of current that goes into the switchboard. Such switches are fed from a generator which has AC frequency and load sharing controls. It also has gauges that show the frequency and synchroscope.

It is important that the amount of electric power that goes into the switchboard is equal to the electric power going. When you take a look inside the switchboard, you will see a bank of busbars.

The busbars, which are generally bare and supported by insulators, are wide strips of copper that connect to switchgear. The busbars act to allow passage of large electric current through the switchboard.

Before the switchboard is opened for maintenance, it is important to isolate the power because the busbars are bare. These active busbars are a deadly source of power. When working on live switchboards, precautionary measures are crucial. Be ready with your protective equipment such as thick rubber mats and gloves, when working with an open switchboard.

Switchboards are isolated and protected with other equipment including substations, motors, high or medium voltage distribution networks and transformers.

Switchgear are also essential a type of electrical distribution device that is used to convert incoming electrical power into several smaller voltages. Switchgear can also be used as a circuit breaker.

There are many different types of circuit breaker switchgear. Vacuum circuit switchgear have minimal arcing. The arc quenches when it is stretched to less the 2 to 3 mm. They?re frequently used in modern medium-voltage switchgear of up to 35,000 volts.

If you need to de-energizing equipment, you can use switchgear. It also clears faults downstream and comes in varied parameters, which include number of panels, electrical specifications and mounting style.

The common types of switchgear are vacuum circuit breakers, oil insulated switchgear, gas insulated switchgear, and a simple open air circuit breaker. Oil insulated switchgear depend on an oil vaporization blast through its arc.

The gas insulated switchgear stretches the arc with a magnetic field and also depends on the dielectric strength of the gas to quench the stretched arc. The open air switchgear circuit breakers use compressed air to blow out the arc. The displaced air that tries to escape thus blows out the arc.

Circuit breakers are a unique type of switchboards that interrupts fault currents. Their design is especially made for interruption of fault currents.

The Classifications of switchboards are based on the current rating, the amount of interrupting rating, by voltage class, insulating medium, construction types, operating method, type of current, interrupting type, and application.

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    Do you want to see the switchboards we have in inventory? We carry many different switchgear. Do you need electrical supplies of all kinds?

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  • Rudy SilvaOwner :
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  • November 30, 2014Date Added :
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