On a lightning arrestor, one end is connected to a phase and the other end to:

• A. Neutral
• B. Battery
• C. ground source
• D. Another phase

Answer: (C)

A lightning arrestor provides a path to earth for transient overvoltages. One end sits on the living phase conductor, and the other end attaches to the grounding system (earth). When a surge occurs, the arrestor conducts and shunts the excess voltage directly to ground, keeping the protected equipment at a safe level. Connecting to neutral isn’t the intended path for surges intended to be dumped into the earth, and tying to a battery or to another phase would create unwanted currents or short circuits. Grounding gives a reliable, low-impedance route for the surge to dissipate.