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  1. k0412d

    Power Transformer Specifications

    One can also refer to "IEC 60076-1 Annex A (normative):Information required with enquiry and order" Giving normal and special information to give for an order.
  2. k0412d

    which IEC standard used for electrical clearance

    The only one I can think of is 60071-1 (Annex A) which provides "Clearances in air to assure a specified impulse withstand voltage installation" Hope it can help. Regards. k0412d.
  3. k0412d

    IEC Thermal Current and busbar withstand

    Hi lume7006, The design of the busbar comes, mainly, down to both mechanical and electrical. Both of them need, among others data, short circuit current info. Here below are the definitions of the terms you're refering from 60909 : Ith (thermal equivalent short-circuit current) the r.m.s...
  4. k0412d

    Electrostatic Ground Shield

    Ok, thanks for the explanation, Ok, considering that transient overvoltage are mostly capacitive it makes sense. One last question before I draw a equivalent scheme to fully grasp the concept. So electromagnetic induced differential overvoltage is negligeable because it is shunt by the...
  5. k0412d

    Electrostatic Ground Shield

    Hi all, My question is a bit wide, and I apologize for that. Often, Electrostatic ground shield are used in Rectifier transformer, I manage to get the following explanation from : Electric power transformer engineering / edited by James H. Harlow. // ISBN 0-8493-1704-5 Ok for the second...
  6. k0412d

    Definition: Switch / disconnect

    Hello, As Scotty said, I would go for the International Electrotechnical Vocabulary (IEV) IEC 60050 Here below is the link for the online version of the IEV (aka Electropedia) : http://www.electropedia.org/ k0412d.
  7. k0412d

    Transformer impedance IEC estandard

    Call me a liar ? :p 60076-5 gives recognized minimal values (not mandated),and states : 'Commonly recognized minimum values for the short-circuit impedance of transformers at the rated current (principal tapping) are given in Table 1. If lower values are required, the ability of the...
  8. k0412d

    Transformer impedance IEC estandard

    Little correction, replace : IEC 60076-5 (Recognized minimum values of short-circuit impedance for transformers with two separate windings) By : IEC 60076-5 (Power transformers – Part 5: Ability to withstand short circuit / Table 1 : Recognized minimum values of short-circuit impedance for...
  9. k0412d

    Transformer impedance IEC estandard

    IEC 60076-5 (Recognized minimum values of short-circuit impedance for transformers with two separate windings) For rated power from 25 to 630kVA, Minimum short-circuit impedance : 4%
  10. k0412d

    Dry Type Transformer Type

    Thanks for the feedback.
  11. k0412d

    Dry Type Transformer Type

    Hello all, I've been studying lately dry type transformer and I realized it was a little more complex than I thought After searching in a book 4 types of dry transformers exist: Cast coil : The winding is reinforced or placed in a mold and cast in a resin under vacuum pressure. Lower sound...
  12. k0412d

    Winding Temperature indicator on Transformer

    Thank you very much for the info, Just to be sure that I'm getting it right, direct measurment is done by optic means to ensure dielectric insulation (Sensor/T° controller device)? And in dry type trfs, pt100 is embedded in neutral end when earthed or regardless of that? THanks
  13. k0412d

    Winding Temperature indicator on Transformer

    Hello all, My question is as said in the Title about Temperature indicator on transformers, for both dry and liquid immersed transformers. Just to be sure that I'm not missing any key point about the measurement here is my understanding for both types, please correct me if anything's wrong...
  14. k0412d

    Explosion vent vs Pressure relief device

    thank you for your responses.
  15. k0412d

    Explosion vent vs Pressure relief device

    Ok you right, For the first 'how about' : it's true I forgot to tell that it was about transformer, sorry. For the 2nd 'how about' : I agree that terminology differs from place, standards manufacturer ect... But it does mean that there is no answer, just that it is not that simple. In that...
  16. k0412d

    Explosion vent vs Pressure relief device

    Hello all, I remember reading a book where was made explicit the definition of the explosion vent and Pressure relief device. From what I remember one would stay open once been activated one the other would close. Since I fail to get the hand on that book I wondered whether I remembered right...
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