Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Power Line noise.

  1. Oct 15, 2011 #1
    Hello, So I have a question about electric power lines.

    Today I was under some large power lines and I noticed some ticking noises. I had never noticed this noise before and was curious

    I thought maybe the current flowing through the lines was too great, and the lines were arcing
    to each other. but that seems silly.

    Could anyone help me out? thanks!

    Note: they were the large lines that run through the large metal tower structure, not the ones along the road... If that changes anything.
  2. jcsd
  3. Oct 15, 2011 #2


    User Avatar
    Gold Member

    What causes the noise emitted from high-voltage power lines--is it static discharge, vibration from the 60-cycle field or something else entirely?

    Robert Dent, president of the IEEE Power Engineering Society, responds:

    "The audible noise emitted from high-voltage lines is caused by the discharge of energy that occurs when the electrical field strength on the conductor surface is greater than the 'breakdown strength' (the field intensity necessary to start a flow of electric current) of the air surrounding the conductor. This discharge is also responsible for radio noise, a visible glow of light near the conductor, an energy loss known as corona loss and other phenomena associated with high-voltage lines."

  4. Oct 15, 2011 #3
    Makes sense, thanks!
  5. Oct 15, 2011 #4

    I have another explaination, as well. On humid days, the buildup of moisture on the insulators can cause a momentary Bzzt noise as current is momentarily carried.

    I've noticed this most often at night as sea breazes blow in. It's a bit odd in that you never know quite when to expect it or from which direction.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook