Hy everyone,
please, help with reference regarding the new codes for transformers such as DD and DY and so on.
Those codes show the major configuration, phase-shift and grounding on Transformers.
Thanks, NNG.
New codes? They look just like the ones that have been around for years. You examples were incomplete incidentally - there would normally be a number which indicates the phase shift between primary and secondary. The HV side is normally indicated by a capital letter, and the LV side is indicated by lower case.
For example Dyn11 indicates HV delta, LV star with the neutral terminal brought out, and a 30 degree phase shift.
Buy yourself the "J&P Transformer Book", which contains all sorts of useful information on transformers including vector groups.
There was also a discussion somewhere on Eng-Tips about this topic not so long since. Try out the search function.
Thank you, ScottyUK.
Your reference book is a good help!
The standard abbreviation seems easy for their users in UK but for others as in US it is a puzzle.
Sincerely, NNG
Please start a new threat when you are asking questions that are not related to the original question.
Discrimination is in short a method to ensure that the breaker nearest to a fault opens first. It can use either time or overcurrent, or a combination of both to achieve correct co-ordination.