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The Last DC Power Grid Shut Down in NYC
cell-block-9 writes "Today the last section of the old Edison DC power grid will be shut down in Manhattan. 'The last snip of Con Ed's direct current system will take place at 10 East 40th Street, near the Mid-Manhattan Library. That building, like the thousands of other direct current users that have been transitioned over the last several years, now has a converter installed on the premises that can take alternating electricity from the Con Ed power grid and adapt it on premises.' I guess Tesla finally won the argument."
most people don't even know who Tesla was or that he pushed for the system that we now use to distribute electricity.
Okay, so if the building was running DC, what did the electronics and appliances inside plug into?
Laughter is the Spackle of the Soul.
do you have a superior system than capitalism in mind?
people are fond of pointing out democracy's many failures too
but the real overriding realization with democracy and capitalism is that however much you think they suck, and they do suck in many ways, they are still better than any other system we can think of and have tried
so please, criticize capitalism. but unless you can enunciate a superior alternative, your criticism means absolutely nothing
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Later elevators still used 600VDC but used a dynamotor
What you're hearing is not a dynamotor, but something called a Ward Leonard drive. It's a fixed-speed motor driving a generator, but its purpose is speed control. The field current of the generator, which is small, is adjusted to control the larger output of the generator. The variable output of the generator then drives the elevator motor. The Ward Leonard drive is thus a big power amplifier. Until power semiconductors got big enough, which wasn't really until the 1980s, this was the most effective way to smoothly speed-control large motors.
A dynamotor has a common field for the input and output sides, but a Ward Leonard drive does not.
Incidentally, the Wikipedia article in Ward Leonard drives is bogus. Here's a better reference.
all you did is enunciate standard real world checks and balances on the ideas
no one expects pure capitalism or pure democracy to ever be able to exist
i'm taking umbrage with radical fundamental departures from the core concepts: communism instead of capitalism, for example, or theocracy versus democracy
not capitalism, tweaked, or democracy, tweaked
the core ideas are always tweaked in one way or another to fit in the real world
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
actually no, that means 80+ years ago that was true but now a high voltage dc transmission system is in fact more efficient, uses less condutors, eliminates need for sychnonization between different systems. HVDC also preferred for undersea long distance transmission because of less capacitive losses.
DC is still far more of a pain to convert than AC at least if you want high efficiancy and high reliability. While HVDC is certainly more efficiant for very long or undersea transmission lines it would be extremely difficult to build a power distribution grid based on it.
note: i'm known as plugwash most places but i screwd up registering that here somehow in the past and now can't register
Capitalism isn't the problem; thievery is.
If you're point had been that Tesla would be the rich, fat cat and that would be bad, then your moral compass would be off but at least your logic would be sound.