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Switch on a transformer but with no load connected

  1. Sep 24, 2009 #1
    If i switch on a transformer but with no load connected to the secondary path.Is the transformer will burn?
  2. jcsd
  3. Sep 24, 2009 #2


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    Re: Transformer

    No. If the voltage is the same as the transformer normally gets, it should run cooler than if it had a load on the secondary.

    A transformer without a load on the secondary is just an inductance. So, the current in this is determined by the supply voltage, the frequency and the inductance and resistance of the primary winding.

    Many appliances switch power in the secondary circuit so that the primary is always connected to the mains. This does waste some power (compared with turning off the primary) and it also leaves the primary vulnerable to mains voltage surges.
  4. Sep 27, 2009 #3
    Re: Transformer

    Yes, if it is a current transformer.
    NO, if it is a voltage transformer.
    Please inform me if you need more explanation.

    Creative thinking is enjoyable, Then think about your surrounding things and other thought products. http://electrical-riddles.com
  5. Sep 28, 2009 #4
    Re: Transformer

    If you are unfamiliar with transformers, I recommend that you do your learning and experimentation with low voltages, like 24V ac. Please do not work with 115V ac until you acquire sufficient education/experience. One mistake could be the last. I've been an EE for 32 yrs., and I never work on 115V ac alone in the lab. I always use one hand when handling hazardous voltages.

    Please heed my advice. The ac power mains are not to be taken lightly.

  6. Sep 28, 2009 #5

    I am trying to get help with rewiring an alternator for wind power generation is there any help here?
  7. Sep 28, 2009 #6
    Re: Transformer

    Here is a site that built an alternator for a wind turbine.
    http://www.fieldlines.com/story/2009/4/4/214533/4539 [Broken]
    Voltage transformers are for a specific frequency. The output frequency of a wind turbine alternator varies all over the place, so don't try to use a transformer. Automotive alternators have a wound rotor with radial field lines, and the stator coil is outside the rotor. The rotor has slip rings for regulating the current. Thw wind turbine alternators have permanent magnet rotors with an axial field, and cannot be regulated. I hope this helps.
    Bob S
    Last edited by a moderator: May 4, 2017
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