What does the need for supplemental braking ensure during a vertical pull of conductors?

The need for supplemental braking during a vertical pull of conductors is crucial for ensuring the safety and control of the conductor. When pulling conductors vertically, there is often a risk of the conductor gaining excessive speed or losing control due to the weight or inertia involved. Supplemental braking systems help manage this by providing additional resistance against the movement, allowing for smoother and safer handling of the conductor.

This safety measure is particularly important to prevent accidents or damage not only to the equipment but also to the people involved in the operation. By ensuring that the conductor can be controlled effectively throughout the pull, the supplemental braking contributes to a safer work environment and minimizes the risk of sudden movements that could lead to mishaps. This is why the correct answer emphasizes safety and control as the primary function of supplemental braking in this context.