Transformer Taps

[JBD]

I am getting a transformer from China, and the nameplate shows taps of: 1, 2, 3, 4, and 5. I am familiar with US transformer nameplates that have taps like: C, D, E, F, and G and are shown with their relative positions on the windings. Comparing the nameplate voltages I know that the US nominal connection is E-G(or 1-4), but the equivalent Chinese connection is 2-5(or F-C).

I know that the physical location of the taps is dependent upon the construction of the coils and the type of jumper used to make the connections. But, are there any standards for tap configurations with 2-1/2% taps 2AN and 2BN or they unique to each type of transformer construction?

 

[dpc]

You really have to rely on the transformer nameplate information. I would never trust that a transformer was built to some standard when adjusting voltage taps.

 

[itsmoked]

And you might want to still check! I have seen several transformers that had mislabeled leads.. Some with disastrous results.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[isquaredr]

taps 1-5 are standard in the uk for distribution type transformers with tap 1=-5%, 2=-2.5%, 3=nominal, 4=+2.5%, 5=+5%. dpc is correct to say check the nameplate as I have seen older transformers with tap 1=+5% were +5 refers to HV winding not voltage.