Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

transformer triping circuit breaker

Options
  • 20-12-2008 11:50am
    #1
    jacaalis
    Closed Accounts Posts: 1 ✭


    when I plug in a 3.3kva transformer into some sockets it trips the circuit breaker - it works fine once the breaker is reset - what causes the trip?


Comments

  • Options
    #2
    KTRIC
    Closed Accounts Posts: 9,463 ✭✭✭KTRIC


    That Optimus Prime is up to his old tricks again :rolleyes:


  • Options
    #3
    RoundyMooney
    Closed Accounts Posts: 10,910 ✭✭✭✭RoundyMooney


    Inrush current most likely.

    Does it trip the relevant circuit MCB, or the ELCB (which is twice the width of the others FYI).


  • Options
    #4
    fishdog
    Closed Accounts Posts: 1,113 ✭✭✭fishdog


    This is normal, nothing to worry about. Large inductive loads such as a transformer will often do this. Here is a software simulation of an inductive load running for just over 1.8 seconds. The trace shows the current through the circuit. Notice how the current surges to about a peak of about 2 amps and then drops down and peaks to only 1 amp after about 1.5 seconds.

    This simulation is at 230 volts RMS and a frequency of 50Hz (similar to mains voltage)

    currentsurgeid3.png
    w800.png


  • Options
    #5
    davelerave
    Closed Accounts Posts: 1,712 ✭✭✭davelerave


    if you connect a load to the 110 side before you plug in the trafo it can prevent this happening.not a problem with industrial sockets just the domestic 'b' types


  • Options
    #6
    bertie1
    Banned (with Prison Access) Posts: 509 ✭✭✭bertie1


    jacaalis wrote: »
    when I plug in a 3.3kva transformer into some sockets it trips the circuit breaker - it works fine once the breaker is reset - what causes the trip?

    The breaker in a domestic installation is B rated , the load of the transformer is a C rated load. Nothing wrong only the domestic mcb is not suitable for the load being plugged in .


  • Advertisement
Advertisement