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    LEADED GASOLINE
    December 9, 1921 - Dayton, Ohio, U.S.A.

    Tetraethyl lead was first given a laboratory test as an anti-knock additive to gasoline fuel. The knock in the one-cylinder laboratory engine was utterly silenced. Even at a strength of only 2-3g grams per gallon (1000 to 1 dilution), it had a remarkable ability to quiet the relentless knocking. This invention of Thomas Midgley, Jr., of the General Motors Research Laboratories, located in Dayton, Ohio, was first put on public sale as ethyl gasoline in the same city on 2 Feb 1923. This invention of leaded gasoline came after seven years of testing at least 33,000 compounds. Previously, on hard acceleration, an engine sometimes made knocking, popping or crackling sounds, which sapped power and could damage the engine.

    MYSTERIOUS LIGHTS IN SKY OVER NORWAY
    December 9, 2009 - Norway

    The Norwegian Metrological Institute has received hundreds of calls from confused observers, but so far has been unable to identify the origin of the skylights that have been seen. Some experts have speculated that the phenomenon might have been caused by a Russian rocket launch, although the Russian embassy has insisted such claims are completely unfounded. Neither meteorologists, astronomers, or the armed forces have offered a solution to the matter. The light was captured by amateur photographer while he was on his way to work at a salmon factory. 'The light appeared for two or three minutes. I could not believe my eyes, and got the shivers and was quite shaken by it,' he said. Another observor, who saw the light phenomena from Sortland in northern Norway, added: 'A large ring appeared, and then spread out, sending a green beam down to earth.'

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