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Converting amperage to voltage

  1. May 18, 2009 #1
    Does anyone know of a way to convert AC amperage to voltage? I need a way to do this so I can use normal electronical components instead of having to design my own.
     
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  3. May 18, 2009 #2

    Averagesupernova

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    By the title of this thread I can tell you need to learn a bit about electricity. Current flowing through a resistor develops a voltage across the resistor. One of the first things taught in electronics. Not sure what you mean by 'designing your own components'. Tell us what your project is please.
     
  4. May 18, 2009 #3
  5. May 18, 2009 #4
    Ohmage.

    Claude
     
  6. May 20, 2009 #5
    You could see a current to voltage converter op-amp design
     
  7. May 21, 2009 #6
    Also, a Hall effect current sensor could be used. Allegro has many of them.

    Claude
     
  8. Jun 3, 2009 #7
    I guess what I mean by designing my own components is that i could just buy what i need instead of hunting to the wastes of Egypt and back to find one that uses a amp based power source.

    I know that almost every type of component uses about the same volt and amp per componenet "class" but when going to a different "class" it only really affects voltage with minimal if any amp change. I also believe the reason for that is that amp level is the only range for best possible human safety.

    I'm not really worried about human safety because I plan on grounding all metal that can be touched (within reason).
     
  9. Jun 3, 2009 #8

    Averagesupernova

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    See my previous post.
     
  10. Jun 3, 2009 #9
    So am I not correct in assuming it's only harder not near impossible to find components that run off of higher amps then volts?
     
  11. Jun 3, 2009 #10

    vk6kro

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    You vanished a couple of weeks ago.

    While you are on line please explain what you are trying to do.


    Re: converting amperage to voltage
    So am I not correct in assuming it's only harder not near impossible to find components that run off of higher amps then volts?

    Do you mean low resistance circuitry? Or what?
    You can have low voltage circuits that use more current but we need to know exactly what you are talking about.
     
  12. Jun 3, 2009 #11
    Ok. I guess I've reached the point to where I have to give up a few details. I'm working on a generator. The problem is it provides higher amps and lower volts. I'm also planning on using this for mainly five different types of components, one being an electric motor. I'm not wanting to have the amp-volt converter be built into the generator so I can pull straight to the motor. I am willing to let the efficiency drop to the other components because they are not so performance important. Does that help?
     
  13. Jun 3, 2009 #12

    vk6kro

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    This is not a time to be secretive.

    You still haven't said what you are trying to do or what sort of generator it is. What is driving it?

    It is low voltage (but how low and is it AC or DC?) and it can deliver a lot of current (but how much current?).

    BUT what do you actually want to do with it? You want to run 5 different sorts of components off it, but what are they and what is their total function?

    You will just get a lot of irrelevant replies or no replies if you don't explain in detail what you are trying to do.
     
  14. Jun 4, 2009 #13
    I already stated that one component was an electric motor. the other 4 run off typical ac house power (110-220v). I'm not finished with the generator but it provides an unknown amount of AC current.(reson: im still in the designing stages. I havent been able to build it yet.)

    And I'm sorry that I'm being secretive but I've been hurt in the past by others stealing my ideas.
     
    Last edited: Jun 4, 2009
  15. Jun 4, 2009 #14

    berkeman

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    It would help if you learned a bit more about electricity. Then you could answer your own questions like this, or at least could ask the questions using standard terminology. Right now, we are having to guess and try to parse what you are asking, so the process is much more drawn out and painful than it needs to be.

    Your statement "it provides higher amps and lower volts" makes no sense. Higher and lower with respect to what? Do you mean it does not produce AC Mains voltages, and that's what you want to convert the output to? Is the output DC or AC? If AC, just use a transformer to step up the voltage to 110Vrms. If DC, use an inverter or a DC motor to AC generator converter.
     
  16. Jun 4, 2009 #15

    Averagesupernova

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    I smell a perpetual motion machine here. When someone new comes to this forum, has some plan for some machine that they do not want to reveal too much information on, and doesn't seem to have a firm grasp on electricity it usually ends up as an attempt at an overunity device. So tell us KelSolarr, whaddaya got?
     
  17. Jun 6, 2009 #16
    Well I guess someone around here has common sense. As for what do I have, and learning about electronics, read my blog.

    https://www.physicsforums.com/blog.php?b=1012 [Broken]

    Again I appologize to anyone who can't or won't help me because of this. I "have a grasp" on electroinics, it's just varying on what part of it. And I do keep up on current or new technologies (like those trying to use graphine for near atom-transistors to use in computers that should speed them up by x10). I grasp theories and theoretical equations really well. I believe thats part of my problem with this. And other basic questions I have.

    And maybe I should try refrazing my initial question. I have AC "generator" providing very high amperage. How do I get it limited or stabilized so I can use home powered electronics off of this generator?

    I use "generator" because I do already know that you cannot "create" energy, just change the form. Like wind powered generators goes from wind energy and converts it to electrical energy.
     
    Last edited by a moderator: May 4, 2017
  18. Jun 6, 2009 #17
    I also have a side question. Am I correct in remembering that Amperage is the frequency (lenght) of the wave and Voltage is the size (height) of the wave?
     
  19. Jun 6, 2009 #18

    berkeman

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    So your generator produces power at a low AC voltage, but can supply lots of current. Fine. Is the output voltage reasonably constant? If so, then a transformer can be used to step the voltage up to AC Mains levels.

    If the output of your generator is not a constant AC voltage, then it will take a more complicated circuit. Probably the most efficient would be to full-wave rectify the low AC output voltage, and follow that with an AC inverter circuit.

    You need to be careful working with AC Mains voltages (110Vrms in the US), because of the shock and fire hazards. Please learn a lot more about electrical safety before messing with AC Mains voltges. Please also be aware that you cannot run off of street power and local power at the same time (generally). You should google "cogeneration of electricity" for more info, and check with your local electric utility company to find out what their policies are for cogeneration.


    EDIT -- BTW, what frequency is the AC output of your generator? Is is constant? If it is anything other than a constant 60Hz (or 50Hz, whatever your local utility uses and what your house appliances are expecting), then you will need to go with the rectification and inverter power conversion.
     
  20. Jun 6, 2009 #19

    Redbelly98

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    If the voltage is too low to power normal household electronics, a simple step-up transformer is what you need. I'm assuming the frequency is reasonably close to mains frequency -- if not, then that is a problem.

    Have you actually built this device, or is it in the design phase?
     
  21. Jun 6, 2009 #20

    vk6kro

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    I also have a side question. Am I correct in remembering that Amperage is the frequency (lenght) of the wave and Voltage is the size (height) of the wave?

    Voltage is the height of the AC signal. If you were looking at a sinewave, you might measure the difference in "height" between the top and the bottom of the sinewave. This is called the "peak to peak voltage".

    Frequency is the number of sinewaves that happen each second.

    Amperage is NOT the same as frequency. It is an old term that refers to current capability.
    Current is a flow of electrons that flow when a voltage is placed across a resistor. The unit of current is the AMP.

    So, a few examples.
    Keys on a piano correspond to higher frequencies as you move to the right of the keyboard. That is they produce more oscillations each second.

    A flashlight bulb would get a voltage of 3 volts and it would draw a current of about 0.3 amps if it had two batteries in it.
    A headlamp bulb in a car would get 12 volts supplied to it and it might draw 6 amps of current. In these cases the frequency would be zero because the voltage is constant DC.

    Did you know you can send Personal Mail on this Forum if you want to keep something more secret? Just click on a nickname (like VK6KRO) and look for the private message part.

    Nobody can design something for you unless you can tell them what voltage you have, how much current it can deliver into a suitable load and what voltage you want and what load it has to supply.
    If you have been confusing amperage with frequency, maybe you know the frequency of your generator?
     
  22. Jun 7, 2009 #21

    Redbelly98

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    Somehow I missed this earlier. To be honest, I think many in this forum are tempted to stop responding after reading this question.

    Whatever it is you are doing, all electronics pretty much starts with an understanding of what current and voltage are. They are the two most basic concepts in electronics, everything else is predicated on an understanding of what they are. In particular, your ability to design a generator requires that you understand them.

    With that, I will recommend that you get a book on electronic circuits, read the opening chapters, and come back here with questions.

    The "gold standard" is Horowitz and Hill's The Art Of Electronics, which may run around $100.00. If you don't want to spend that much, you could browse around at a bookstore for something cheaper.

    Good luck.

    EDIT / p.s.
    To put it simply: current (what you call amperage) is the flow of charge in a circuit. Voltage can be thought of as the force that moves charge through a circuit ... though strictly speaking it is an energy potential per unit charge, and not a force.
     
  23. Jun 7, 2009 #22
    So far. Only two (maybe three but we'll see on that.) of you have actually listened to me. And I will answer some of these questions but I do believe I have gotten many answers. And yes. I do believe many will stop responding. If anyone actually read my blog, those still reading already know that I am expecting that. I only want help from those that are willing to help. I don't have money to just go drop it on books to educate myself and my side question was because thats how I was taught in my electronics class or so I remember. I apologize, when I wrote my blog I was distracted and I forgot to mention that.

    As for the technical questions. yes it is still in design phase. More because I need to figure out what the motor(s) are going to use. The motors are the only things not running on home based power. I can very easily change the frequency of the generator. So I guess I have my theories/calculations backwards. All of which has been answered by the one of the only people actually listening or understanding me. Meaning I only have one question left that I have already asked that has not been answered. Should I not be hare? Am I not somewhere where anyone will help me? Thats the only reason I joined was because this looked to be a place where people help other people with their problems.
     
  24. Jun 7, 2009 #23

    Averagesupernova

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    Look KelSolarr, I don't know how to tactfully put this, but I'll try. The reason that you won't get an answer from here that you are looking for isn't because you won't tell us what you are doing. It is because quite simply you don't understand electricity. Getting frequency and current confused is like confusing the color of a pail and the amount of water it will hold. They are both properties of the pail but neither one really has anything to do with the other. It is VERY understandable that anyone without any education concerning electricity wouldn't know current from frequency. There is nothing wrong with that. But in this case, you come in here claiming that you are prepared to make your own components but prefer not to, which implies you do know something about electricity and then confuse current and frequency. NO ONE will take you seriously anymore.
    -
    Now I will try to answer the question that is in the title of this thread in the only way I see that the question makes sense in the first place: There is no way to convert amperage to voltage and vice-versa. However, if you have a voltage source that is lower than you want but able to supply way more current than you need, as others have pointed out you would use a transformer to step the voltage up at the expense of reducing available current. Ignoring inefficiencies of the transformer, if you use a transformer that is stepping up the voltage by a factor of 10 you will reduce the available current by a factor of ten. In other words, watts in = watts out. No gain here, only loss due to the inefficiency of the transformer.
    -
    I'm sure this won't help you with your project but I'm hoping that it does show you that you cannot make shortcuts and carelessly skip all the book learning. Don't have the money to buy books? Ever hear of a library?
     
  25. Jun 7, 2009 #24

    Redbelly98

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    I just discovered that the Horowitz and Hill book is online, i.e. free. "Skip ahead" to page 1 at this link:
    http://books.google.com/books?id=bk...a=X&oi=book_result&ct=result&resnum=9#PPP1,M1


    Sorry if we sound unduly harsh. But the impression is that where you need help, where your problem is, is with understanding the basic principles first. Electronics can be dangerous to work with, and you seem to be talking about dangerously high currents and voltages.

    I know you have your reasons for keeping specifics out of the discussion, but that has made it difficult and time consuming to discover that what you need is probably a step-up transformer -- again (and I cannot stress this enough) after you have learned and understand the basic principles.
     
  26. Jun 7, 2009 #25
    And I take it that none of you are willing to help me learn the basics? If that is the case then I shall give my thanks and bow out peacefully.
     
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