Which device is used to prevent fatigue failure of lines experiencing prolonged vibration?

• A. ACSR wire
• B. New insulators
• C. Vibration dampers
• D. All of the above

Answer: (C)

When lines experience wind-driven vibration for long periods, the conductor undergoes many stress cycles. Fatigue failure happens not from a single overload but from those repeated tiny stresses accumulating over time. The device that directly addresses this is a vibration damper, which attaches to the line to absorb and dissipate the energy of the vibrating conductor. By reducing the amplitude of the vibration, the peak dynamic tension the line experiences is lessened, slowing or preventing fatigue damage over many cycles.

The other options don’t provide this energy-dissipation function. ACSR wire describes the conductor material, not a method to curb vibration-induced fatigue. New insulators are for electrical isolation and mechanical support, not dampening vibrations. Therefore, the device specifically designed to prevent fatigue failure from prolonged vibration is the vibration damper.