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    COLDEST TEMPERATURE ON EARTH SURFACE
    August 9, 2010 - Antartica

    the record low surface temperature in Antartica was -135.8ºF (-93.2ºC), colder than the freezing point of dry ice. It was determined from analysis of remote-sensing satellite data later announced on 9 Dec 2013 at the annual meeting of the American Geophysical Union. The location was in pockets scattered near a high ice ridge between Dome Argus and Dome Fuji, two summits on the East Antarctic Plateau. August is winter in the Southern Hemisphere, and the temperature resulted from the geographical nature and weather conditions in the pockets. The World Meteorological Organization official records are for air temperatures made a couple of meters above the surface. That recorded lowest temperature, made in Jul 1983 at the Vostok Research Station, Antarctica, remains at -128.6ºF (89.2ºC).

    PROTECTOGRAPH
    August 9, 1904 - New York, U.S.A.

    The Protectograph check-writing machine was patented under the title Printing-Stamp by Libanus McLouth Todd of Rochester, New York (U.S. Patent No. 766,853). It was designed to protect against check forgers by marking and embossing the amount on a check, thereby preventing the amount thus shown to be later dishonestly changed to a higher value. The apparatus had co-axial printing wheels with lines of raised type forming a series of numbers and suitable words. A check would be placed between the wheels and a platen. An inked felt-covered roller applied ink to the type as the wheels were turned to select the chosen imprint. The platen surface had a yielding material, such as rubber. When actuated by a hand-lever, it was raised from beneath the check and embossed the paper against the type.

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RANDOM QUOTES

  • The wealth of the nation
    by Earth Day, Gaylord Nelson

    "...The wealth of the nation is its air, water, soil, forests, minerals, rivers, lakes, oceans, scenic beauty, wildlife habitats and biodiversity that'as all there is. That'as the whole economy. That'as where all the economic activity and jobs come from. These biological systems are the sustaining wealth of the world...."
  • Rules for Happiness
    by Immanuel Kant

    "...Rules for Happiness: Something to do, Someone to love, Something to hope for...."

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  • 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. More vehicles
    about Stolen On New Year's

    More vehicles are stolen on New Year's Day than any other holiday throughout the year. (So does that mean thieves are having their last fling before changing their ways or are they trying for a big score to start the New Year?)

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