Wall ac signal?

Discussion in 'General Electronics Chat' started by EEDude, Nov 19, 2008.

  1. EEDude

    Thread Starter Active Member

    Nov 18, 2008
    If you were to splice the wires on an ac power cord and measure the + and - signals would they look the same, or shifted 180 degrees? Or something different?? thanks!
  2. SgtWookie


    Jul 17, 2007
    It depends upon the AC you're looking at!
    In the US, residential service is 120v/240v. There is L1, L2, and Neutral.
    L1 and L2 are the opposite ends of a center tapped transformer, and Neutral is the center tap.

    At the service panel, Neutral is tied to earth ground for safety.
    At a typical 120v outlet, you'll have L1 or L2 (Hot), Neutral and Ground.
    If you used Ground as a reference, you'd find very little difference between Neutral and Ground, and about 120v RMS between Hot and Ground. If you do find more than a few volts difference between neutral and ground, call an electrician.

    In a 240v outlet (say for a dryer or other 240v appliance) you might just have L1, L2 and Ground. L1 and L2 are of equal amplitude and opposite in phase (180° apart).