# Transformer vector group

Given the transformer connection of the primary and secondary winding, in example: Yd11, how do I connect the LV side so I get the correct phase-shift? I understand what clock vector groups represent, and I can draw the vector diagram, but I find it quite hard to connect the LV side to get the correct phase-shift. • what phase shift do you want? if Yd11 is your input and it is a star connection, you must know what your required output phase shift it. – JonRB Jan 13 '19 at 0:03
• I just want to know how to connect both Y and delta, so the phase shift between the primary and secondary voltage is 11 hours, or 330 degrees. – user186059 Jan 13 '19 at 0:09 simulate this circuit – Schematic created using CircuitLab

Figure 1. Phasor diagrams for the Y-Δ transformer.

The original diagram is badly drawn with inconsistent use of colour.

• Since the each primary and secondary pair share a leg of the transformer core the voltages in each winding have to be in phase. This is indicated on Figure 1a where the connected phasors represent the primaries.
• Figure 1c shows the result when the secondaries are connected in delta. simulate this circuit

Figure 2. (a) shows both the P-N and P-P phasors.

In Figure 2 we can see that if we were to analyse using the phase to phase (P-P) phasors that there is a phase shift between (a) and (c).

in example: Yd11, how do I connect the LV side so I get the correct phase-shift?

You just connect them up in Y and D and the phase shift will be automatic. I think you should look for a better text book than your image came from.