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  1. #1
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    circuit to mesure ac voltage

    Hello everyone,


    I am doing this circuit.Click image for larger version. 

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    Here is the result I got,Click image for larger version. 

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    However, in reality I could not get this signal.i don't know why
    PS: I got the AC voltage by circuit a voltage divider.

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  2. #2
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    Re: circuit to mesure ac voltage

    So show us the exact "reality" circuit you used.
    What AC and DC voltage sources do you have?
    Zapper
    Curmudgeon Elektroniker



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  3. #3
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    Re: circuit to mesure ac voltage

    Superposition theorem
    The superposition theorem for electrical circuits states that for a linear system the response in any branch of a bilateral linear circuit having more than one independent source equals the algebraic sum of the responses caused by each independent source acting alone, where all the other independent sources are replaced by their internal impedances.
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  4. #4
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    Re: circuit to mesure ac voltage

    ac =1.5 V

    dc =1.5 V
    here is the schema in complis that I wanted to achieve
    Click image for larger version. 

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    however at the beginning I wanted to buy the op amp.

    i tested the circuit with out amp op i jsute tested the input but i don't find what i need find



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    Re: circuit to mesure ac voltage

    Hi,

    Please focus on the "non working curcuit".
    It makes no sense to show the "working" circuit, but complaining another circuit.
    --> photo, exact schematic, exact components and wiring

    And please give unambigous informations.
    ac =1.5 V
    In technical discussions we mainly use the RMS value.
    In opposite to this in mathematical discussion one often uses the "amplitude value"

    With sine value:
    1V RMS = 1.414Vp (peak) = 1.414V ampltude = 2.828Vpp (peak-to-peak)
    = 1.414V × sin(wt)

    Btw: the simplest solution I see is just a capacitor and a resistor:
    AC --- C --- (output) --- R --- 1.5VDC.

    But there are several ways, with and without Opamp, with and without capacitor...
    You first have to decide your requirements / specifications.

    Generally: if the real results differ a lot from the expected results, then - most probably - you are doing something wrong.

    Klaus
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  6. #6
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    Re: circuit to mesure ac voltage

    Coupling capacitor or transformer required for mixing AC signal + DC

    for exampleClick image for larger version. 

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  7. #7
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    Re: circuit to mesure ac voltage

    thanks for the informations so if i understood you i must use a capacitor with the ac input


    1 members found this post helpful.

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