CentraCore Optical Ground Wire (OPGW)

Sept. 22, 2015
AFL CentraCore Optical Ground Wire (OPGW) is preferred for its compact size and ability to house up to 96 fibers in a diameter starting at only 12mm. Its small profile offers an exceptional solution to the diameter and weight concerns on many of today’s overloaded transmission towers where an existing shield wire needs to be replaced with an OPGW cable. With the fiber-bearing stainless steel tube securely protected in a hardened aluminum pipe then covered with a layer(s) of aluminum clad steel and/or alloy wires, this condensed design offers a more robust configuration than those options with only a bare stainless steel tube covered by wires. Optical Ground Wire (OPGW) is a dual functioning cable. It is designed to replace traditional static / shield / earth wires on overhead transmission lines with the added benefit of containing optical fibers which can be used for telecommunications purposes. OPGW must be capable of withstanding the mechanical stresses applied to overhead cables by environmental factors such as wind and ice. OPGW must also be capable of handling electrical faults on the transmission line by providing a path to ground without damaging the sensitive optical fibers inside the cable.AFL has been manufacturing Optical Ground Wire since 1985 and has supplied hundreds of thousands of kilometers of cable since our inception. CentraCore OPGW was developed by AFL as a “blend” of expertise from our other cable designs. It takes AFL’s stainless steel tube technology found in the HexaCore OPGW family and couples it with AFL’s aluminum pipe drawing capability used in the AlumaCore OPGW family. A fiber-bearing stainless steel tube is encased in a thick-walled aluminum pipe, providing the durability needed for installation and long-term performance while adding a conductive aluminum layer that boosts the fault current capacity of the otherwise small profile design. The fibers are grouped in bundles of 12 with color-coded threads denoting the different bundles. ;The standard color sequence (Blue, Orange, Green, Brown, etc.) is used for the individual fibers as well as for the threads identifying the bundles.Another positive feature of the CentraCore design is that the cable and hardware can remain consistent even though the fiber count may vary. The CentraCore family allows a user to modify the fiber count up to 96 without impacting the cable’s overall profile or diameter. Whether the need is for 48 fibers today and then 96 fibers tomorrow, by selecting a CentraCore option, a utility can ensure that their cable diameter and thus the associated attachment hardware will never change. As such, a utility can greatly reduce the amount of spare parts needed for various fiber count cables because all cables are the same size.