Pro/Forums - View Single Post - its the OCH ipkonfig Review all over again...

nexxo · 08-26-2002, 05:12 AM

uhh, Redleader,

The way I understand it the AC vs DC debate came about in 1900 when Tesla and Edison were proposing different systems to provide power for the World Fair... AC was chosen because it could offer more power, presumably.

Their argument went something like this (see http://www.nextekpower.com/acrobat/ACDC2.pdf):

Nicola Tesla; "Alternating Current will allow the transmission of electrical power to any point on the planet, either through wires or through the air, as I have demonstrated."

Thomas Edison; "Transmission of AC over long distances requires lethally high voltages, and should be outlawed. To allow Tesla and Westinghouse to proceed with their proposals is to risk untold deaths by electricide."

Tesla; "How will DC power a 1,000 horsepower electric motor as well as a single light bulb? With AC, the largest as well as the smallest load may be driven from the same line."

Edison; "The most efficient and proper electrical supply for every type of device from the light bulb to the phonograph is Direct Current at low voltage."

Tesla; "A few large AC generating plants, such as my hydroelectric station at Niagara Falls, are all you need: from these, power can be distributed easily wherever it is required."

Edison; "Small DC generating plants, as many as are required, should be built according to local needs, after the model of my power station in New York City."

AC - Alternating current could be carried over long distances via a relatively small line given an extremely high transmission voltage of 50,000 volts or above. The high voltage could then be transformed down to lower levels for residential, office and industrial use.

DC - While higher in quality and more efficient than alternating current, DC power could not be transformed or transmitted over distances via small cables without suffering significant losses through resistance.

The Result - AC power became the standard of all public utilities, overshadowing issues of safety and efficiency and forcing manufacturers to produce appliances and motors compatible with the national grid.

I'm not too sure AC makes better motors. DC generally motors don't last too long under continuous load because they have brushes, which wear out. Magnetic drive motors do not, of course, but require enough juice to generate a magnetic field strong enough to make the motor spin. High voltage (110V or 240V) does the trick nicely, hence all these mains powered aquarium pumps. Low voltage (12V to 24V) motors bypass the problem by requiring more amps. This is somewhat harder to deliver, and less efficient, but luckily a PSU will do this easily.

08-26-2002, 05:12 AM	#38
nexxo Cooling Savant Join Date: Jul 2002 Location: Brimingham, UK Posts: 385	uhh, Redleader, The way I understand it the AC vs DC debate came about in 1900 when Tesla and Edison were proposing different systems to provide power for the World Fair... AC was chosen because it could offer more power, presumably. Their argument went something like this (see http://www.nextekpower.com/acrobat/ACDC2.pdf): Nicola Tesla; "Alternating Current will allow the transmission of electrical power to any point on the planet, either through wires or through the air, as I have demonstrated." Thomas Edison; "Transmission of AC over long distances requires lethally high voltages, and should be outlawed. To allow Tesla and Westinghouse to proceed with their proposals is to risk untold deaths by electricide." Tesla; "How will DC power a 1,000 horsepower electric motor as well as a single light bulb? With AC, the largest as well as the smallest load may be driven from the same line." Edison; "The most efficient and proper electrical supply for every type of device from the light bulb to the phonograph is Direct Current at low voltage." Tesla; "A few large AC generating plants, such as my hydroelectric station at Niagara Falls, are all you need: from these, power can be distributed easily wherever it is required." Edison; "Small DC generating plants, as many as are required, should be built according to local needs, after the model of my power station in New York City." AC - Alternating current could be carried over long distances via a relatively small line given an extremely high transmission voltage of 50,000 volts or above. The high voltage could then be transformed down to lower levels for residential, office and industrial use. DC - While higher in quality and more efficient than alternating current, DC power could not be transformed or transmitted over distances via small cables without suffering significant losses through resistance. The Result - AC power became the standard of all public utilities, overshadowing issues of safety and efficiency and forcing manufacturers to produce appliances and motors compatible with the national grid. I'm not too sure AC makes better motors. DC generally motors don't last too long under continuous load because they have brushes, which wear out. Magnetic drive motors do not, of course, but require enough juice to generate a magnetic field strong enough to make the motor spin. High voltage (110V or 240V) does the trick nicely, hence all these mains powered aquarium pumps. Low voltage (12V to 24V) motors bypass the problem by requiring more amps. This is somewhat harder to deliver, and less efficient, but luckily a PSU will do this easily. __________________ "There is a thin line between magic and madness"