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

What kind of this transformers

  1. Jul 21, 2010 #1
    Hello friends

    What is the use of 1:1 transformer and are they using currently in hi-tech circuits.

  2. jcsd
  3. Jul 21, 2010 #2
    These transformers are called isolation transformers because they simply separate circuits. One of the main use of these kind of transformers are for galvanic isolation. You simply segragate two circuits and couple them by the magnetic flux in the transformer's core.

    I don't know if they are used in hi-tech circuits (what is hi-tech anyway? this term is very vague) but they are used in a lot of applications.
  4. Jul 21, 2010 #3


    User Avatar

    Staff: Mentor

    Sounds like a schoolwork question. What do you think the answer is?
  5. Jul 21, 2010 #4
    schoolwork question :smile:

    no, not schoolwork question, actually its confused me,that why we have to couple circuits
    with the help of Transformer,
  6. Jul 21, 2010 #5


    User Avatar

    Staff: Mentor

    What kind of circuits do you need to couple with the help of a 1:1 transformer? What frequency ranges?
  7. Jul 21, 2010 #6
    I don't follow the original question, but pulse transformers are often 1:1.
  8. Jul 23, 2010 #7


    User Avatar
    Science Advisor

    Well the most important reason is to electrically decouple the two circuits. Grounds cannot be passed through transformers so one with a 1:1 ratio will just isolate the two circuits. Take for example an electrical test workbench, isolation transformers are used to prevent inadvertent grounding for safety reasons while testing electrical devices.

  9. Jul 23, 2010 #8
    thanks a lot
  10. Jul 24, 2010 #9
    another application is to use 1:1 transformer (three phase) in Star-Delta or Delta-Star configuration. Delta-Star for eliminating zero sequence currents, like in distribution having single phase unbalanced loads. Star-Delta for deriving zero sequence voltages, specially in protection relay circuits.
  11. Jul 24, 2010 #10


    User Avatar
    Science Advisor
    Gold Member

    A 1:1 transformer will eliminate common-mode interference, such as hum etc.. They are (or were) commonly used in audio circuits for that reason, on either end of a long audio line which could have unwanted currents induced in it. The volts on the downstream secondary will have the same signal as the volts on the primary at the sending end - as long as the cable is a twisted pair with no effective area for the induction of volts from magnetic fields.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook