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TODAY IN HISTORY

    FULL-LENGTH ANIMATED FILM
    December 21, 1937 - Los Angeles, California, U.S.A.

    Snow White and the Seven Dwarfs, Walt Disney's first full-length (83 minutes), animated film opened in Los Angeles, California. Using the story adapted from Brothers Grimms' Fairy Tales, it was the first commercially successful film of its kind. This pioneering film made use of the multi-plane camera to achieve an effect of depth, introduced human characters modeled on live actors, and used larger painted cels. After two years and a then astronomical $1.5 million to create, it was released for its premiere during Christmas of 1937. Disney had to mortgage his house to pay for the film's production. This followed within a span of just 12 years since the first black and white talking Mickey Mouse in Steamboat Willie (1928).

    PATENT FOR PEANUT BUTTER AND JELLY SANDWICH
    December 21, 1999 - U.S.A.

    A U.S. patent was granted for making a "Sealed Crustless Sandwich," (No. 6,004,596), to David Geske and Len C. Kretchman of Menusaver, Inc. From 1995, they had successfully marketed their product to schools. Smucker bought the company and introduced "Uncrustables." Shortly, Smucker alleged patent infringement by Abbie's Foods, Inc., a grocer and caterer, warning them to cease selling a crustless peanut butter and jelly sandwich. Albie's appealed to federal court (11 Jan 2001). Challenging the patent, Albie's and requested (9 Mar 2001) a Patent Office re-examination. A patent requires non-obviousness, and is invalidated by any prior useage. Despite Smucker's further patent filings and appeals, the Patent Office finally cancelled the improvident patent (8 Dec 2006).

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RANDOM QUOTES

  • Until a man duplicates a blade of grass
    by Earth Day, Thomas Alva Edison Inventor

    "...Until a man duplicates a blade of grass, Nature can laugh at his so-called scientific knowledge. Remedies from chemicals will never stand in favorable comparison with the products of Nature, the living cell of a plant, the final result of the rays of the sun, the mother of all life...."
  • All of us have a God in us
    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...."

RANDOM FACTS

  • 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. Salary
    about Steve Jobs

    Steve Jobs' annual salary was $1, just enough to keep company health benefits.

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 :
  • Free Articles / LifetimeArticle Type
  • November 30, 2014Date Added :
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