1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Why don't I get shocks on neutral wire?

  1. Dec 11, 2012 #1
    Why don't I get shocks on neutral wire???

    In my textbook the AC current is defined to be one which changes its direction periodically.
    So according to the text both the wires of the AC supply should give you shock, but I felt the real shock when I observed that the neutral wiring didn't shook me!!!

    So what is different in household wiring????
     
  2. jcsd
  3. Dec 11, 2012 #2

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    Re: Why don't I get shocks on neutral wire???

    The neutral wire is called neutral because it is, well, neutral. The other one has AC, this gives AC between the two cables.
     
  4. Dec 11, 2012 #3

    rcgldr

    User Avatar
    Homework Helper

    Re: Why don't I get shocks on neutral wire???

    Link to diagram of household wiring (USA style):

    hsehld.htm

    At my home, depending on location, I measure up to 1/2 volt difference between "neutral" and "ground", due to issues like impedance. The US National Electrical Code translates into a max of 3.6 volts between neutral and ground for 120 volt outlet, and 6.6 volts for 240 volt outlet.

    Going back to that diagram in hsehld.htm, at my area, that transformer has a single phase 6900 volt line and ground on the input side of the transformer, and a 240 volt transformer with grounded center tap (for 120 volt) output.

    "Stray voltage" can be an issue for locations like dairy farms. Wiki article:

    http://en.wikipedia.org/wiki/Stray_voltage
     
    Last edited: Dec 11, 2012
  5. Dec 11, 2012 #4

    Nugatory

    User Avatar

    Staff: Mentor

    Re: Why don't I get shocks on neutral wire???

    Why the higher limit between neutral and ground for a household 240v circuit than 120v? The 240v circuit is two 120v circuits on opposite phases, so shouldn't be able to pull anything further away from ground than a 120v circuit? Just wondering... I'm away from my copy of the code right now.
     
  6. Dec 11, 2012 #5

    davenn

    User Avatar
    Science Advisor
    Gold Member

    Re: Why don't I get shocks on neutral wire???

    In Australia, New Zealand and maybe a few other countries
    the neutral line is grounded at the household fuse/meter panel

    Dave
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Why don't I get shocks on neutral wire?
  1. I don't get it (Replies: 9)

Loading...