When using a set-screw type pulling head, the conductor should fill what percentage of the barrel connector's cross-section?

The correct response indicates that when using a set-screw type pulling head, the conductor should fill 40-60% of the barrel connector's cross-section. This percentage range is crucial for ensuring that the conductor fits securely within the connector, allowing the set screws to effectively grip the conductor without damaging it.

Filling this percentage also helps to create a balance between providing a reliable connection and avoiding unnecessary stress on the conductors. If the conductor fills too much of the barrel, it could lead to difficulty in inserting the conductor or cause mechanical stress during the pulling process. Conversely, if the conductor fills too little of the barrel, there may be inadequate contact with the set screws, resulting in a weak connection that could fail under load.

Additionally, this fitting range promotes a strong and effective electrical connection while accommodating thermal expansion and contraction of the conductor during operation. It is essential for maintaining the integrity and performance of electrical installations, particularly during pulling or installation processes where tension is applied.