What is the max pulling force of 3/4 pair cables?

• A. 100 newtons/22 pounds
• B. 90 newtons/20 pounds
• C. 110 newtons/25 pounds
• D. 120 newtons/27 pounds

Answer: (C)

When installing copper cables, you must limit the pulling force to protect the conductors and the jacket from damage. The maximum pulling force is a rating that reflects how much tensile stress the cable can safely endure during installation.

For a 3/4 pair cable, the commonly accepted maximum pulling force is about 110 newtons, which is roughly 25 pounds. This value accounts for the cable’s size and construction: it’s large enough to necessitate more force than smaller cables, but it must stay within a limit to avoid stretching or damaging the insulation, conductor terminations, or jacket as you pull through conduits or troughs. In practice, you aim to stay at or below this limit, using lubrication and proper technique to prevent exceeding it.

The other options represent values that are either below or above the typical safe threshold. Going under the limit risks not pulling the cable effectively, while exceeding it increases the chance of damage during installation. Therefore, 110 newtons (25 pounds) is the best choice.