Recent content by denni89627

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    Need help converting ac to dc

    What you're looking for is a rectifier. Remember that the Vdc out of the rectifier will be a function of the ac input. It's usually easier to transform the ac going into the rectifier to a value that will give you the desired dc output than to convert the output dc into another value.
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    Three Phase Power Concerns

    Averagesupernova is 100% correct, my mistake. If you draw out 3 sin waves 120 degrees apart you will see that they would maintain a stable rotation in a motor with poles 120 degrees apart as well. connecting 3 phases to a node would be Wye operation, you would be well served to study Delta...
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    Timer switch questions

    Allen Bradley makes excellent timer relays that you can do this with. They have many functions and even an adjustable dial with adjustable time units so you can set the timer anywhere from under a second to a couple of days. They are bulletproof. I have retro fitted many of them into use for...
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    Three Phase Power Concerns

    Of course 3 phase is important, basically every large motor in any building is a 3 phase motor. Elevators, HVAC, etc. If you have a good foundation on AC, all you need to know is the phases lead/lag each other by 90 degrees. Are you asking how a 3 phase motor works? Motors are the main reason...
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    Two Phase Power For Contactor Coil?

    Is the thing running? I don't see how. AB contactors are good, but if you're coil is 120v you're going to ruin it if you try to operate it with 208v. (For the record AB has contactors with 208v coils, so maybe that's what you have. It should be printed on the side of the contactor) As for wiring...
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    Questions regarding something in Feynman's lectures.

    Interestingly this is why we abandoned the original Edison DC grid for the more efficient and easier to propagate Tesla AC system. To achieve similar results a DC system would need gigantic conductors and copper is expensive. Tesla = Genius
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    3d glasses.

    I'm thinking you could have more depth gradients than the two you would see on what you describe.
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    Need help for my project

    Same thing with a Peltier. Think of it as a solid state sterling engine if you want, it will only generate voltage if there is a temperature differential between the top and bottom sinks. I did a similar project making an Ipod charger that used a candle on one side of a Peltier and a CPU heat...
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    House Power Out of Phase?

    I use phase protection relay's all the time in my line of work. (Elevator mechanic). Everybody is correct that your manual would be better written if it said "in proper phase relation" rather than "in phase". If my elevator motors lose a phase they begin to sound like a sci-fi movie UFO sound...
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    Self exiting dynamo question

    Sounds like you're re-inventing the transformer. :smile:
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    Power issues with power drill physics help needed please

    The inrush current on a motor is huge compared to up to speed current draw. This is why large motors are started with a wye-delta setup (or soft starters mostly now). It is also why your lights dim when you first turn on a hair dryer or vacuum cleaner. I would bet short circuit amperage is very...
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    Wave freq vs freq of its oscillating source

    I could see why a beginners book would say that, but you have to realize this is not accounting for frictional/heat losses which you would always have in the real world. A non perfect wave transmitting medium (everything) would not act as expected. Imagine laying a floor speaker on its back and...
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    Is It Possible To Shape An Electric/Plasma Arc?

    I don't think your speaker would sound too hot in an argon tube.
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    3 phase rectifier with cap filter w/overheating wire.

    Are you saying you want to run this rectifier at less than 300 amps or that you want your circuit to handle the high amp output? To lower your amperage you could modify your SCR driver. (You could use the SCR's to rectify less of the AC waveform). Otherwise it seems you simply undersized your...
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    ARRRH I'm gonna explode. This is my pet hate!

    What a joke... So many people will eat this up too. Way to go Michiu Kaku.... (I think that was his voice, right?)