🔍 Key Concepts

• Turns ratio of a transformer and how it relates primary voltage to secondary voltage on a per-phase basis • Difference between line voltage and phase voltage in a three-phase wye versus delta connection • How the specific winding connections shown in figure "2" (primary and secondary) affect the relationship between applied 480 V and the voltage at A2-B2-C2

💭 Think About

• First, decide whether the 480 V given is a line-to-line voltage or a line-to-neutral voltage on the primary, and how that appears in a wye system. • Look at the figure and determine whether the secondary (A2-B2-C2) is connected in wye or delta. How does that choice change the relationship between phase voltage and line voltage? • After finding the secondary phase voltage using the 4:1 turns ratio, convert that phase voltage to the line-to-line voltage that actually appears between A2-B2-C2.

✅ Before You Answer

• Verify from the drawing whether the primary is wye-connected with a neutral point N1, and what that implies for primary phase voltage when the line voltage is 480 V. • Verify from the drawing whether the secondary A2-B2-C2 windings are connected in wye or delta. • Compute: primary phase voltage → divide by turns ratio (4:1) → secondary phase voltage → then convert to secondary line voltage and match it to one of the choices.