Live working on ACSS conductors

Since 2006, RTE has been installing Aluminium Conductor Steel Supported (ACSS) type low-sag cables on the network. These steel-core conductors are covered by annealed trapezoidal-shaped aluminium wires, giving them superior power ampacity compared to conventional round wires conductors. Thanks to a lower coefficient of thermal expansion they can carry greater currents. However, if the conductor reaches higher temperatures, the outer layer of the conductor is subject to ductile behaviour. Consequently, the trap wires are more sensitive to surface and structural damage and there is a need to control the temperature of the conductor when the operator carries out maintenance work in contact with the conductor.