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Following are he minimum information and Data which to be shown on a transformer nameplate.The standards require the following information and data for transformers rated above 500 kVA
(Suppose 1000kVA = 1MVA.
• Name of manufacturer
• Serial number
• year of manufacture
• Number of phases
• kVA or MVA rating
• Frequency
• Voltage ratings.
• Tap voltages.
• Connection diagram.
• Cooling class
• Rated temperature in °C
• Polarity (for Single Phase Transformers)
• Phasor or vector diagram (For Polyphase or Three Phase Transformers)
• % impedance.
• Approximate mass or weight of the transformer
• Type of insulating liquid.
• Conductor material of each winding.
• Oil volume (of each transformer Container/Compartment)
• Instruction for Installation and Operation

Name Plate Rating Of a Transformer
The Data on the Nameplate of transformers contains of kilo-Watts rating, Voltage Rating,Frequency, Number of Phases, Temperature, Type of Cooling, % Impedance and Reactance,  Name of Manufacture,Year of Manufacture etc.
A Typica Nameplate of a Transformer as follow.

S.No.   Description of Data to be given                         Ra-marks for example
[1]                 [2]                                                                     [3]=================================================================
1.    Manufacturer’s Name:                                             ABB/206788
2.    Manufacture’s Serial Number                                 224106
3.    Kind of Transformer                                                 Power Transformer
4.    236839Relevent Standard Year                             I.S/P.S/B.S/ IEC /DIS/JIS NEMA
5.    Year of Manufacture                                                 2013
6.    Number of Phase                                                     3
7.    Rated Power                                                           1000kVA  = 1MVA
8.    Rated Frequency:                                                    50Hz
9.    Rated Voltages:                                                       HV  33 kV,  LV 11 kV,
10.    Rated Currents                                                      HV______,LV_______.
11.    Vector Group Symbol                                            __________________
12    % Impedance Voltage
         ( At Raed Current)                                                  __________________
13.    % Reactance Voltage  in  % :                               __________________
14.    Types of Cooling                                                   ONAM
15    .Total Weight                                                            __________Kg
      ..Mass or insulating Oil                                             __________Kg
     ..Transportation Weight                                             __________Kg
     ..Untanking Weight                                                     __________Kg
16.    Insulating liquid ( if Not Oil) Types:                       ______________
17.    Quantity of Oil ( Liters):                                         __________
18.    Details about Tap-Changer                                  __________
19.    Rated  insulation Level:                                        __________
      ..Power-Frequency withstand Voltage                   kV(rms)
20.    Other                                                                      …………………….

Also shown in below image.

Below is a 100kVA (Three-Phase) Transformer nameplate. 
Click image to enlarge. 

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  1. This comment has been removed by a blog administrator.

  2. Hi,<br />Very good blog post I love your site keep up the great posts.

  3. I agree! thanks for this information.

  4. Hi, On some plates we can see Y/delta ikons with triangle. Would you explain me, pls, what is that dash-line inside of triangle sign for?<br />Thanks<br />

  5. DDS-84-2007 ?<br />What is that notation?<br />Is that a standard in which transformer built or some type of manufacturing number or date in which the transformer is built?

  6. thanks, can we find efficiency and iron losses in name plate?

  7. where is insulation level ?

  8. <a href="; rel="nofollow">Electrical transformer manufacturers</a> provides different content notation on name plate. This blog provides standard name plate notification of the transformer thanks for sharing imaging information about name plate. <br /> <br />

  9. how we get Transformers tolerance

  10. Zeeshan Sohail

    40 MVA transformer also called 20 26 ( May be Size or some else, i don’t know ) Can anyone told me that what is 20 26? i mentioned a cell no in the comment for text messaging or What’s app .. +92-306-6287879

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