IEEE 1138:2009 pdf free download – IEEE Standard for Testing and Performance for Optical Ground Wire(OPGW) for Use on Electric Utility Power Lines
4.2 Design of fiber optic unit
The fiber optic unit shall be designed to house and protect the optical fibers from damage due to forcessuch as crushing, bending, twisting, tensile stress, and moisture. The fiber optic unit and the outer strandedmetallic conductors shall serve together as an integral unit to protect the optical fibers from degradation dueto vibration and galloping, wind and ice loadings,wide temperature variations, lightning and fault current,as well as environmental effects that may produce hydrogen.The fiber optic unit may include an aluminumtube, channeled aluminum rod, stainless steel tubing, or aluminum-coated stainless steel tubing; but is notlimited to these designs.
4.2.1 Metallic tube
The fiber optic unit may include a tube such as stainless steel or aluminum to house the fibers. The tubemay be fabricated as a seamless tube, seam welded, or a tube without a welded seam.
The fiber optic unit may include a stainless steel tube with an aluminum protective coating to house thefibers. The coating shall completely cover the tubes leaving no exposed areas of tubing that can makeelectrical contact either directly or indirectly through moisture, contamination, protrusions, etc., with thesurrounding stranded wires described in 4.1.
5.3 Optical—Field acceptance testing
Upon receipt of the oPGW cable from the supplier，it is recommended that the purchaser performacceptance tests in order to verify that the optical characteristics of the fiber meet the order requirementsand to determine if optical fibers have been damaged during shipment. The results of these tests and thesupplier’s certified quality control information, which is attached to each reel, shall be compared to thefiber requirements specified in the purchase order.
These tests may be performed by either of two methods. The first method is to use an optical time delayreflectometer(OTDR) and the second is to use a light source and a power meter.Access to only one end ofthe cable is required using the OTDR. Use of the OTDR method means it is not necessary to remove theprotective covering from one end. Both ends of the cable shall be accessible when using the light sourceand power meter method. It is necessary to remove at least a portion of the covering to use the light sourceand power meter.A 1 km length of fiber may be spliced between the OTDR and the cable to improveresolution near the cable end. However, it shall be noted when using an OTDR, breaks or damage within10 m of either end of the fiber from where the OTDR is connected may not be detectable. If a reel failsusing the single-end OTDR method, then before rejection of the reel, the fiber(s) in question shall be testedfrom the opposite end and the results for the fiber(s) averaged. Mechanical splices or a bare fiber adapterhave been used successfully to conduct these tests. If using a bare fiber adapter，there shall be noattenuation loss.