Exam 29: Three Phase Transformers

A wye-delta transformer has a turns ratio of 2:1. It has a secondary line voltage of 480 V. The secondary is connected to a wye-connected three-phase resistive load of 50 Ω in each phase. What is the primary phase current?

A wye-connected secondary has a phase voltage of 277.14 V. What is the line voltage?

In an open delta with a center-tapped transformer, label the two ends of the center-tapped transformer as L₂ and L₃ and label the high leg as L₁. The current flow in the neutral (center tap) is equal to _____.

For installations that will have both three-phase and single phase loads on a three-phase transformer, the utility company often provides a(n) _____ three-phase transformer.

In three-phase transformer connections, the primary leads are labeled with the letter _____ and the secondary leads are labeled with the letter _____.