State Grid Xuzhou Power Supply Company: Installation of Height Limitation Facilities to Prevent External Damage to Transmission Lines

XUZHOU, China, Aug. 26, 2025 /PRNewswire/ -- Recently, Mr. Sun Weizhi, a transmission line operation and maintenance staff member from State Grid Jiangsu Xuzhou Power Supply Company, visited a rural road intersected by the 110-kilovolt Yaoshan Line (Section 5#–6#). Under the supervision of the local traffic management department, he directed the installation of removable height limit racks to prevent over-height vehicles from entering and potentially damaging the transmission infrastructure.

With the ongoing acceleration of urbanization, infrastructure and factory construction projects in various towns and townships across Xuzhou have increased by more than 30% annually. This growth has led to a corresponding rise in incidents involving accidental collisions with transmission lines and damage to roadbeds caused by over-height or overweight vehicles and construction machinery. These issues have increasingly drawn public and administrative attention.

In response, State Grid Xuzhou Power Supply Company, in collaboration with the local traffic management department, has implemented flexible installation strategies for height limit racks. This initiative establishes a three-dimensional protection system integrating "physical barriers, warning notifications, and collaborative management." The system not only enhances the safety and reliability of transmission line operations but also protects the public's traffic rights and interests.

Considering the large number and widespread distribution of temporary construction projects, removable height limit racks are primarily used to facilitate rapid deployment and dismantling across different regions. For routes serving specific enterprises or industrial buildings, fixed-type height limit racks are preferred. For example, on the road leading to a hazardous waste disposal facility, which is crossed by the 110-kilovolt Yaolong 914 Line, frequent passage of ultra-heavy vehicles posed significant safety risks. After the installation of fixed height limit racks, risks such as accidental line contact, roadbed damage, and pedestrian injuries have been effectively mitigated.

Regarding the height specifications for the racks, after consultation with the traffic management department, the company established clear standards based on the lowest point of the transmission line above the rack beam. These standards specify a minimum clearance of 7.5 meters for 110 kV lines, 8 meters for 220 kV lines, and 10 meters for 500 kV lines, ensuring compliance with required safety distances between the conductors and the height limit structures.

In addition, for certain critical areas, the company has equipped the height limit racks with audio-visual alarm systems. When vehicles approach, these systems automatically trigger a warning: "Strictly Enforced Height Limit of 7.5 Meters on This Section." Simultaneously, the system sends alerts to the monitoring center, forming a dual safeguard mechanism of "on-site interception + remote monitoring." This approach significantly reduces the likelihood of line collisions, line breakages, and tower collapses.

SOURCE State Grid Xuzhou Power Supply Company