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!

Homework Help: Tapping in power systems

  1. Jul 29, 2015 #1
    1. The problem statement, all variables and given/known data
    What is meant by the term tapping in power system , I studied in my textbook that generally from feeders no tapping is taken to the consumers , therefore current loading of feeder remains the same along its length. I was not getting what is being referred here ..?

    2. Relevant equations

    3. The attempt at a solution
    I am familiar with the tapping we use in case of transformer which is the varying the number of turns , which further changes the voltage ratio.. Is this the same sense tapping in power supply system is being used??
    Last edited by a moderator: Aug 4, 2015
  2. jcsd
  3. Jul 29, 2015 #2
    Unless there is a definition I am not aware of, tapping is exactly what you describe.

    Primary substation transformers (generally) have on-load tap changers via a diverter and a large number of taps. There are many methods to automatically control the tap when you have two or more transformers in parallel - master/slaves; TAPP ; circulating current etc...

    Secondary substation transformers and pole-mounted transformers have off load tap changers and just a few taps (usually about 5) which are set when the transformer is installed. Off load is a bit of a misnmoer, becasue the transformer has not only to be off load but isolated.
  4. Jul 30, 2015 #3


    User Avatar

    Staff: Mentor

    Based on what you provide here, I would conclude that tapping refers to connecting a couple of wires to take power to the premises of each consumer along the route. Where consumers take current from a power line, there will be a drop in remaining current as you progress away from the power station. It's saying that feeders don't have consumers tapping on along the route; feeders carry power between networks, and it is the local network that is responsibe for distributing that power to consumers.
  5. Jul 30, 2015 #4
    In 20 years in the power industry (UK) I have never heard that defintion of tapping

    what you describe is called a CONNECTION.
  6. Jul 31, 2015 #5


    User Avatar

    Staff: Mentor

    Perhaps ranju could indicate which country his textbook was written for?
  7. Jul 31, 2015 #6
    that would be helpful!

    You may very well be right, I've just never heard a (consumer) connection called a tap before
  8. Jul 31, 2015 #7


    User Avatar
    Science Advisor
    Gold Member

    One origin of the term tapping in comes from the time when telegraph signals were carried long distance with a single wire and earth return . After making a connection at a remote location operator 'tapped in' a Morse code sequence to tell the master operators that the connection was live . Phrase later came to be used more generally to denote making ad hoc connections to any system .

    Same root as phone tapping .
  9. Jul 31, 2015 #8
    thats fine

    but utility companies don't make ad hoc connections; and tapping has a defined meaning: the operation of a tap changer.

    If, in a power systems context, tapping is being used to mean anything other than the operation of a tap changer; then that is very shoddy indeed.
  10. Aug 4, 2015 #9
    Well.. Its written in India..
  11. Aug 5, 2015 #10
    well, I googled

    india power system tapping

    and it came up lots of articles about stealing power....

    maybe the OP needs to ask someone who works in India?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted