Which of the following best describes a corner-grounded delta connection?

• A. One corner is connected to ground
• B. All corners are grounded
• C. No corners are grounded
• D. Ground is connected to the center of a winding

Answer: (A)

In a delta connection, the three windings form a closed triangle. A corner-grounded delta ties one corner of that triangle to earth, giving the system a single reference point. The corner connected to ground sits at earth potential (zero volts), while the other two corners float relative to ground but still carry the line voltages between themselves and to the grounded corner. This setup offers a defined ground reference without grounding all corners or the center of any winding, which are not characteristics of a corner-grounded delta.