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  1. #1
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    What is the difference between AC and DC capacitors and how does AC capacitor work?

    What is the difference betewwn AC and DC capasitors and how does AC capasitor works?.
    Im asking this becuse till now i have look into capasitor as into "charge box" which can be charged with some DC power and this will result into high voltage and low power. So i dont understand what shoud AC capasitor meens. Can he deliver more AC power or what...

    Generaly, how does AC capasitor works ?

    •   Alt24th November 2006, 11:18

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    capasitors

    Quote Originally Posted by Beginner19
    What is the difference betewwn AC and DC capasitors and how does AC capasitor works?.
    Im asking this becuse till now i have look into capasitor as into "charge box" which can be charged with some DC power and this will result into high voltage and low power. So i dont understand what shoud AC capasitor meens. Can he deliver more AC power or what...

    Generaly, how does AC capasitor works ?
    Capacitor is capacitor, AC or DC does not matter. Only case when it matters is in case of electrolytic polarised capacitors. They DON'T work with AC.



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    ac capasitor

    i guess AC capcitor are high frequency capcitor....

    the major difference is polarity and frequecy of material.....


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    difference between ac dc capacitors

    Hi Tom,

    I guess AC capcitor are high frequency capcitor
    I agree and i was thinking about that. But if they are HF capasitors then they are producing greater AC power as "standard" capasitors or ?



    •   Alt24th November 2006, 13:47

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    capasitor

    I agree and i was thinking about that. But if they are HF capasitors then they are producing greater AC power as "standard" capasitors or ?
    To clarify, a capacitor doesn't produce any power in the sense that it is not a source like a battery. It simply stores energy.

    To get back to your question, I think what you may mean by AC/DC capacitors is that an AC capacitor is not polarized and can store energy in either direction. A DC capacitor is polarized and will only store energy when connected properly...otherwise it could blow up.

    A capacitors best performance will always be at a DC voltage (correct me if I'm wrong here). However, there are probably some capacitors out there that are designed to work better with high frequency components than a standard capacitor.

    If you want to see the performance characteristics of a capacitor, look into LaPlace Transforms. Its a relatively easy way to see how caps work as filters and how they respond to AC/DC signals.

    One more thing to consider, a


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    •   Alt24th November 2006, 16:02

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    function of capasitor

    AC capacitor is not polarized and can store energy in either direction.
    Yes, that's it I have made simple example and it's working perfect.

    One more thing regarding caps capasity.
    Do you know the hardware difference between 25microF and 50 or 100microF ?.
    Is the dialectric same or not...

    Am asking this becuse i want to make my own ( just as test ) and i dont have any clue how to expand capasity.



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    difference between ac & dc capacitor

    Hi
    Simply you can consider a capacitor is composed of 2 parallel plates when you connect the plates to a voltage source there will be electric between the 2 plates this electric field will bond electric charges on the plates ( those charges are delivered by the source) this what we call a capacitor so therte is a capacitance between any 2 objects whether small or large capacitance as for ac capacitor it accepts positive charges on any plate and so for negative charges ie if you have 2 plates forming a capacitopr , plate A and plate B you can find +ve charge on A or -ve charge it doesn t matter ,as for dc capacitor it has a polarity indicated on its terminals if you reverse the polarity it may leake or explode the mosat famous dc capactiors are electrolytic and tantalum.
    Regards



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    the differance between ac and dc capacitors

    Regarding physical differences between a 25 and 50 uF capacitor.....Capacitance is directly proportional to the Area of the parallel plates and inversely proportional to the Distance between them. The properties of the insulating material between the plates also comes into play, however, i doubt if the same manufacturer would use a different dielectric for each size cap...they likely just vary the area and distance...but i don't know for sure.

    As for building your own....I wouldn't recommend it. Caps are cheap enough and easy to obtain. A poor cap can be a great shock hazard or a horrible cap.



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    what might be the function of capasitor

    One more question regarding AC capasitor (20 microF).

    If i charge AC capasitor with 50V of direct current i can measure ( direct connected on multimeter ) 2mA of DC.

    1.) Is it possible that this kind of capasitor can "produce" AC current. I have writen "produce" becuse sometimes i can measure AC current but the capasitor is charged with DC current ??

    2.) what is the simples way to convert this DC capasitor voltage to AC voltage ?



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    how to connect capacitor to ac

    Beginner19,
    An AC capacitor is a non-polarized capacitor that is designed to operate with relatively high currents, such as in motor starting and motor run applications. There is no fundamantal difference between an AC capacitor and any other non-polarized capacitor. AC capacitors have low ESR (equivalent series resistance) to minimize internal heating due to I^2R losses in the capacitor. AC capacitors are typically designed with packages that efficiently dissipate internally generated heat.
    Regards,
    Kral



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    dc capasitor

    Capacitor can have different function.
    and mainly classified as polarized or non-polarized type.

    They are be used for AC or DC signal application.

    When capacitor are use to coupling AC signal
    between circuit stages,
    they are refered as coupling capacitor.
    Capacitor can also perform signal filtering function.
    Capacitor in DC signal, capacitor can be use to
    stablise or block DC signal.
    There are names for various type of function of capacitor.

    It is a matter of how you connect up the capacitor,
    for the function you want.

    www.siongboon.com



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