How tight should the ADSS fiber optic cable be tightened

ADSS fiber optic cables should be tightened to achieve the planned sag without exceeding the cable's rated tension, typically not exceeding 600 lbF (2700 N) during installation.

Maximum Pulling Tension

During installation, the maximum pulling tension should not exceed 600 lbF (2700 N) to prevent damage to the delicate optical fibers inside the cable. This limit may vary depending on the cable manufacturer and installation method, so always refer to the cable specification sheet for the exact allowed tension. Using a controlled paying-off method and tensioners ensures the cable is pulled steadily without sudden jerks that could overstress the fibers.

Span Tension and Sag

After the cable is pulled, it is placed in the pole hardware under span tension, which is calculated to achieve a 1% installation sag. This sag ensures the cable can safely accommodate wind, ice loads, and temperature changes without overstressing the fibers. The span tension is typically lower than the maximum pulling tension and is adjusted for each span based on pole height, span length, and environmental conditions.

Installation Precautions

Avoid excessive tension, crushing, or bending beyond the minimum bend radius specified by the manufacturer. Use proper suspension and dead-end clamps to distribute tension and allow slight movement for thermal expansion and wind-induced vibration. Prevent friction, abrasion, or contact with sharp edges during installation to protect the cable sheath and fibers.

Temporary or permanent guys should be installed at tension points to avoid unbalanced loads on support poles.

Summary

The ADS

S cable should be tightened just enough to achieve the planned sag while staying below the maximum rated tension. Over-tightening can break fibers or damage the sheath, while under-tightening can cause excessive sag and unsafe clearance. Always follow the manufacturer's specifications and calculate span tension based on environmental loads and span length to ensure long-term reliability.