Which term describes the high-voltage conductor that should be avoided for control circuits in a high-leg delta?

Which term describes the high-voltage conductor that should be avoided for control circuits in a high-leg delta?

• A. Wild leg
• B. Neutral leg
• C. Ground leg
• D. Phase leg

Answer: (A)

In a high-leg delta, one winding is center-tapped to provide a neutral for 120/240 V service. The conductor that is connected to the far end of that center-tapped winding is the wild leg. It shows about 208 V to neutral, unlike the other two legs, which are 120 V to neutral. Because control circuits and standard 120 V devices are designed for 120 V between hot and neutral, the wild leg would overvolt these circuits and cause damage. Therefore, the wild leg is the one to avoid for control circuits in this system. The neutral is the center-tap, used with the two non-wild legs for 120 V loads, while the ground is a separate protective path.

In a high-leg delta, one winding is center-tapped to provide a neutral for 120/240 V service. The conductor that is connected to the far end of that center-tapped winding is the wild leg. It shows about 208 V to neutral, unlike the other two legs, which are 120 V to neutral. Because control circuits and standard 120 V devices are designed for 120 V between hot and neutral, the wild leg would overvolt these circuits and cause damage. Therefore, the wild leg is the one to avoid for control circuits in this system. The neutral is the center-tap, used with the two non-wild legs for 120 V loads, while the ground is a separate protective path.