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Hot and live wires

  1. Apr 26, 2013 #1
    does ac current always flows from hot to neutral wire.if so where is the end of the neutral wire?
  2. jcsd
  3. Apr 26, 2013 #2


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    AC current (alternating current) flows back and forth typically 60 times per second...or 60 hz (in USA).

    It can flow back and forth to the neutral if it is wired that way....or it can flow line to line, or hot to hot so to speak.

    I assume you are referring to a 240/120 house panel? If so, the neutral is center tapped at the secondary of the transformer to the house cutting the voltage in half. Line to line is 240....line to neutral is 120volt.

    If you are reffering to something else, please be more specific in your question.
  4. Apr 26, 2013 #3
    The "hot " leads refer to being able to deliver the power, the neutral is - at some point, connected to ground, and is LESS hazardous and on its own not used to provide the power, and as PSP reported it is AC - the current flows back and forth.

    The end of the neutral is in two places - just to confuse you - it is connected to a winding on the transformer supplying the power and to ground.
  5. Apr 27, 2013 #4


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    Both conductors are involved in the transfer of Power. You can't say the Neutral is any less of a contributor than the Live conductor. (No current is supposed to flow through the Earth / Ground). It just so happens that the Potential Difference between Neutral and Earth is (near) zero but it's of no consequence in the power situation.
  6. Apr 27, 2013 #5


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    And just to make it "in your face clear" on a 240 volt single phase system:

    Hot to hot.....240 volts
    Hot to neutral....120 volts
    Hot to ground...120 volts
    Neutral to ground.....nada....zero volts.

    The neutral and ground are tied together in your main house panel.....and the neutral and ground are tied together in the secondary of its transformer. The grounds are both "earthed" as well at the main panel and transformer secondary.
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