What are the two displacements associated with a wye-delta connection?

In a wye-delta connection, the two displacements that are relevant pertain to the phase angles used in converting between the wye (Y) and delta (Δ) configurations of electrical circuits. For a three-phase system, the phase angle displacements are typically calculated based on the relationship between the two configurations.

The correct answer identifies the two specific angles, which correspond to the phase shifts given in a 120-degree system typical for three-phase circuits. When examining phase differences in this context, 30 degrees and 210 degrees are related to the shifts one would expect when transforming from a wye to a delta configuration, particularly focusing on the rotation of vectors in the complex plane. This is crucial in understanding how the voltages and currents related to each configuration are represented.

In contrast, the other options represent angles that are either unrelated or not consistent with the standard phase displacements needed in a wye-delta conversion, thereby making them incorrect in this context. Understanding these specific angles helps in analyzing and designing circuits effectively, particularly in rotating machinery and power systems.