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I would like to know the mechanism of LCR bridge

  1. Sep 29, 2005 #1
    Who can tell me the theory about the LCR bridge to measure capacitance?
  2. jcsd
  3. Sep 29, 2005 #2


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    Staff: Mentor

    Google to the rescue: lcr bridge measure capacitance

    http://chem.ch.huji.ac.il/~eugeniik/instruments/test/bridges.html [Broken]
    Last edited by a moderator: May 2, 2017
  4. Sep 29, 2005 #3

    The ac bridges work just like the wheatstone bridge except you have to balance the impedance, which is dependent upon the frequency. By taking a ratio of impedances, you can calculate the capacitance or inductance as required.

    The ac bridges are pretty much obsolete in modern test equipment. Today's LCR meters work by introducing a small sinusoidal voltage to a network (capacitor, inductor, resistor or combinations), and measuring the current that flows into the circuit. By the ohm's law, the impedance can be calculated Z = V/I, from which capacitance or inducance can be deduced.
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