Red Seal Electrician Practice
Wiring and componentsQuestion 813 of 1506

How are the long overhead power line conductors usually built and supported?

  1. Bare metal, hung from towers on insulators
  2. Paper-insulated copper hung from wooden crossarms with no insulators
  3. Enamelled wire clamped directly to the steel towers
  4. Rubber-covered wire pulled inside steel pipe full of nitrogen
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Correct answer: Bare metal, hung from towers on insulators

Overhead line conductors are bare, so the insulating supports at the towers keep them isolated from the structure.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 12.3: Conductor Ampacity

Practice wiring and components

Questions last reviewed: 18 October 2026