Answer: The primary difference lies in their composition. OPGW (Optical Ground Wire) is a hybrid cable that serves a dual purpose: it acts as a traditional ground wire for lightning protection and also contains optical fibers for communication. Its core is metallic, typically made of aluminum-clad steel or aluminum, which provides high mechanical strength and electrical conductivity.

In contrast, ADSS (All-Dielectric Self-Supporting) cable is entirely non-metallic, or "all-dielectric." It uses high-strength aramid yarns or glass-reinforced plastic (GRP) as strength members. This composition makes it non-conductive, lightweight, and completely immune to electromagnetic interference, but it cannot function as a ground wire.