4 Dyn11 Transformer nameplate, what does 4 stand for?? 2

[mschrepfer]

4 Dyn11 Transformer nameplate, what does 4 stand for??

 

[prc]

In old British Standards for transformers,various connections were tabulated in tables.eg 0 connections were in table 1, 11'o clock connections in table 4 etc.So when connection was mentioned, the table number also used to come with it.

 

[jack6238]

The transformer connections were listed by group numbers and these number referred to the phase displacements. These were:
Group 1(1)-zero degrees, clock hour number 0.
Group 11(2)- 180 degrees displacement, clock hour number 6.
Group 111(3)- minus 30 degrees disp., clock hour 1.
Group 1V(4)- plus 30 degrees, clock hour 11.

Here's an excellent resource.
J&P Transformer Book-A Practical Technology of the Power Transformer,Butterworth,numerous editions~$150.