what is the difference between a potentiometer and a variable resistor?

Discussion in 'General Electronics Chat' started by mahela007, Sep 13, 2008.

  1. mahela007

    Thread Starter Active Member

    Jul 25, 2008
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    what the difference between a potentiometer and a variable resistor ?
     
  2. hgmjr

    Moderator

    Jan 28, 2005
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    A variable resistor is made up of a potentiometer wired with the center leg tied to one or the other end of the pot. This permits it to act like a variable resistor.

    hgmjr
     
  3. SgtWookie

    Expert

    Jul 17, 2007
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    Here's a schematic to illustrate hgmjr's assertation.

    When wired as a potentiometer, the wiper (usually the middle connection) acts as a tap. In the circuit on the left, Vout could be a voltage anywhere between +V and -V, depending upon the setting of the pot.
     
    PackratKing likes this.
  4. hgmjr

    Moderator

    Jan 28, 2005
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    Another term used in place of variable-resistor is "rheostat" as mentioned by sgtwookie.

    hgmjr
     
  5. mik3

    Senior Member

    Feb 4, 2008
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    A variable resistor is a two terminal component which you can vary its resistance by rotating an axis or by sliding a conduct along its axis (big one, usually used in labs for experiments).

    A pot is a three terminal component which you can use as a variable resistor (as SgtWookie said) and to obtain a variable voltage on one of its pins by rotating its axis by your fingers (panel mounted pots, you can use them frequently) or by a screwdriver (trimmers, usually used on PCB's to adjust something for a few times because they fail if you use them frequently).
     
  6. bertus

    Administrator

    Apr 5, 2008
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