______ generators have only three wires, one for each phase. Whereas the ______ generator has four wires, one for each phase plus a neutral or ground wire.

• A. Delta / Wye
• B. Wye / Delta
• C. Star / Delta
• D. Delta / Delta

Answer: (A)

Three-phase windings can be connected in different ways, and that choice changes how many wires you bring out and whether a neutral is available. In a delta connection, the three windings form a closed loop with three external terminals, and there is no neutral brought out. That’s why a delta generator typically has three wires. In a wye (star) connection, the windings all meet at a common neutral point, so you have three phase outputs plus a neutral, giving four wires in total. The neutral provides a reference and return path for phase-to-neutral voltages, while the line-to-line voltages are related by the square root of three.

So the blanks are filled with delta for the first and wye for the second.