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    WIRELESS TELEPHONE AT WHITE HOUSE
    November 21, 1919 - White House, U.S.A.

    President Wilson used a radio telephone set up on the south portico of the White House to direct the maneuvers of a dozen army airplanes flying over the Potomac river several miles away. His telephoned directions went direct to the flight commander in the air. The instrument was similar to those used by American aviators in France in the latter part of World War I. Col. C. C. Culver actively developed the equipment. He began the project in Aug 1910. No new invention was needed, only adaptation and adjustment of existing techniques. By Aug 1916, he was able to send a radio telegraph signal from a plane. Enlisting expert help from the telephone companies, by Oct 1917, voice messages could be send between a plane and the ground. The system was put into service for military wartime use.

    EDISON'S PHONOGRAPH
    November 21, 1877 - New York City, U.S.A.

    Thomas Edison announced his invention of his "talking machine" - the tin-foil cylinder recorder that preceeded the phonograph. He appears to have envisioned it as a business dictation machine. In Sep 1877, he wrote that its purpose was "to record automatically the speech of a very rapid speaker upon paper; from which he reproduces the same Speech immediately or years afterwards preserving the characteristics of the speakers voice so that persons familiar with it would at once recognize it." The indented tin foil, however, would survive only a few playings. By the first public showing of a phonograph, which took place in New York City in early Feb 1878, its practical applications had not yet been realized.

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  • A Change is Gonna Come
    by Meredith Grey

    "...Change; we don't like it, we fear it, but we can't stop it from coming. We either adapt to change, or we get left behind. It hurts to grow, anybody who tells you it doesn't is lying. But here's the truth: Sometimes the more things change, the more they stay the same. And sometimes, oh, sometimes change is good. Sometimes change is everything...."
  • No Man is Above the Law
    by Theodore Roosevelt

    "..."No man is above the law and no man is below it; nor do we ask any man's permission when we require him to obey it. Obedience to the law is demanded as a right; not asked as a favor."..."

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Circuit Breakers :

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ARTICLE INFORMATION :

Most non-electricians know little about circuit breakers. Are you planning to redo the wiring in your home? Using the wrong breaker can cause you a lot of power failures. Quiz your electrician to know more about breakers.

ARTICLE CONTENT :

A circuit breaker is an electrical device used to automatically break open an electrical circuit when it becomes overloaded. This is a safety precaution that can save a home or building from having a major fire or electrical disaster.

To determine the ideal breaker, you have to consider the type of voltage you are using, the trip point, and the overload protection. These are important factors for the safety of your home and family.

There are different types of voltage breakers; the low voltage circuit breaker is the most common type, which is used in homes. Low voltage breakers are the easiest way to install, since you only have to install them on breaker panels.

Miniature circuit breakers or MCBs use the lowest low voltage. It is known to carry electricity of not more than 100 amps; MCBs are also capable of holding electric charges of not more than 1,000 amps. Next to MCBs, are the Molded Case Circuit Breakers or MCCBs.

MCCBs are ideal for 1,000 amps and can safely disconnect from electricity that goes beyond ten times its capacity. They are also called a magnetic circuit breaker, because they use an electromagnetic power solenoid to break the circuit when there is too much electricity flowing through it.

Medium Voltage Circuit Breakers are the next type. Its capacity is to hold amps that can reach between 1,000 and 72,000 before they break. Their performance is relative to the model and brand. Westinghouse breakers are known for its quality of performance.

Medium Breakers are found in large buildings and businesses, and are enclosed in switchboxes or indoor cabinets. Under this type of breaker are three sub-types, vacuum, air, and SF6 breakers.

The vacuum breakers can maintain a power arc in a vacuum by letting air back into the breaker when it is tripped. An air Circuit breaker is equipped with two spring loaded contacts close together in an air-enclosed environment, when the breaker is tripped; the spring snaps open and pushes the contacts away from one another.

SF6 breakers have an arc produced in a chamber of sulfur hexafluoride gas, which reacts to the presence of higher than a regular voltage. It increases in density to stop the arc.

The high voltage breakers are the ones that are capable of holding more than 72,500 volts of electricity. They are found outdoors in a chain-link enclosure together with high voltage power lines. They are operated by solenoid switch which activates the fill the arc-chamber, when too much power flows through them.

The trip point is the second consideration in choosing the ideal circuit breaker. The point at which the breaker will trip can be set at low, medium or high sensitivity to prevent your wiring from heating.

Breaker overload protection is critical. Westinghouse breakers have overload protection that are similar to hydraulic and earth leakage breakers, providing custom protection. This type of circuit breaker senses ground faults and excessive flow of electricity.

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  • Relectric
    At relectric you will find the circuit breakers you want. We have many brands of circuit breakers you can choose from.

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