Fiber optic cable is the communication medium in wind farms between the substation, turbines and meteorological towers. It is generally a 24 strand fiber cable installed in a dedicated orange conduit in the same trench with power cables. In case the collector system consists of overhead lines, the the fiber cable can be either incorporated in the shield wire and OPGW cable is used or an overhead all dielectric self supporting (ADSS) cable is used.
Slice boxes are required on different locations of collector system to facilitate the installation, operation and maintenance of the system. On overhead systems Splice boxes would be required at the poles adjacent to the wind turbines. However, for the end of line wind turbines and met towers, the splice box can be eliminated. In this case the contractor shall leave enough fiber cable rolled -say 100 meters- at the pole to be installed in the underground trench to the wind turbine. After installation, the fiber ends at the patch panel at the base of the wind turbine or met tower.
Regarding ADSS in underground installation, clearance from power cable shall be taken into account. There are studies that suggest it is not suitable to run ADSS beside the power cables. A phenomena known as dry-band arching deteriorates the cable when it is subject to electrical fields as well as conductive contamination (water, dirt). Please refer to the below link.
The ADSS supplier can be contacted to verify the application, knowing it will be laid along side Collector system power cables. Note that this dilemma also applies to the ADSS coming into the station as well
