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    DEBATE OVER USE OF THERAPEUTIC CLONING OF EMBRYOS
    August 12, 2004 - USA

    The continued debate over the use of therapeutic cloning for stem cell research continues to gather pace both in America and other countries of the world . Many believe that the research will lead to medical breakthroughs in Multiple Sclerosis, Parkinson's and Alzheimer's disease. Many believe that the research raises serious questions of 'ethics' and embryos have rights to life which is a gift from God not from a scientist in a lab.

    IBM PC
    August 12, 1981 - United States

    IBM introduced the PC personal computer for $1,600 base price. It shortly eliminated most other machines suitable for home or small business such as those with the S-100 bus, running on CP/M or their own operating system. The PC was developed in less than a year at IBM's Boca Raton Florida facility by using existing off-the-shelf components. The IBM-PC established the dominance of the Microsoft operating system. The IBM PC hardware design also became the industry standard for PC compatibles, with the ISA bus. Its Intel 8080 processor speed was 4.77 MHz, and it used from 16K up to 640K of memory. Data storage choices included 5.25" floppy drives, cassette tape, and later hard disks.

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    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 :
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  • November 30, 2014Date Added :
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