17-22 impedance from the loop system to the ground is at least 50 mega ohms. After successful
completion of megger test, test loop system resistance using an electronic ohmmeter to verify loop system resistance is less than 0.00885 ohms per foot. 1726 -4 MEASUREMENT AND PAYMENT Lead -in Cable (____) will be measured and paid as the actual linear feet of lead -in cable furnished, installed and accepted. Measurement will be made by calculating the difference in length markings located on outer jacket from start of run to end of run for each run. Terminate all cables before determining length of cable run. If markings are not visible, measurement will be point to point with no allowance for sag. Twenty -five feet will be allowed for vertical segments up or down poles. Payment will be made under: Pay Item Pay Unit Lead -in Cable ( ____ ) Linear Foot FIBER -OPTIC CABLE 1730 -1 DESCRIPTION Furnish and install single mode fiber -optic (SMFO) communications cable and drop cable assemblies, fiber -optic cable storage racks (snow shoes), communications cable identi fication markers, lashing wire and all necessary hardware. 1730 -2 MATERIAL Refer to Division 10. Item Section Cable Identification Markers 1098 -11(C) Fiber -Optic Cable 1098 -11 Lashing Wire and Hardware 1098 -7 Storage Racks 1098 -11(D) Furnish m aterial, equipment and hardware under this section that is pre-approved on the ITS and Signals QPL available on the Department’s website. 1730 -3 CONSTRUCTION METHODS
A.General Prior to installation p rovide cable manufacturer’s attenuation and Optical Time Domain Reflectometer (OTDR) testing data for each reel of cable upon request by the Engineer . Install SMFO communications cable, snow shoes, communications cable identification markers, lashing wire and all necessary hardware. Comply with manufacturer’s recommendations. Install communications cable on signal poles, utility poles, messenger cable and in conduits as required to bring the fiber -optic cable into and, if necessary, out of each splice enclosure. Take all precautions necessary to ensure cable is not damaged during storage, handling and installation. Do not violate minimum bending radius of 20 times the radius of cable diameter or manufacturer’s recommendation, whichever is greater. Do not step on cable nor run over cable with vehicles or equipment. Do not pull cable over or around obstructions or along the ground. Determine lengths of cable necessary to reach from termination -point to termination -point. Install cable in continuous lengths between approved splicing facilities. Additionally, provide a sufficient amount of slack cable to allow for an ad ditional 20 feet of cable to be
17-23 present after removal of outer sheath for termination. Measure slack cable by extending
cable straight out of cabinet door. Keep cable ends sealed at all times during installation to effectively prevent the ingress of moist ure. Use approved heat shrink cable end cap. Do not use tape to seal cable ends. Before installing cable, provide 1 electronic copy of cable manufacturer's recommended and maximum pulling tension. Do not exceed manufacturer’s recommended pulling tension . Use pulling grips containing a rotating swivel. Coil cable in a figure -8 configuration whenever cable is unreeled for subsequent pulling. Install fiber -optic cable in separate 2 inch risers with heat shrink tubing or conduits. Do not share risers or c onduits containing fiber -optic cable with other type cable.
B.Aerial Installation Double lash fiber -optic cable to messenger cable with one 360° spiral per foot. Use pole attachment hardware and roller guides with safety clips to install aerial run cable. Maintain tension during the pulling process for aerial run cable by using an approved mechanical clutch (dynamometer) device. Do not allow cable to contact the ground or other obstructions between poles during installation. Do not use a motorized vehicle t o generate cable pulling forces. Use a cable suspension clamp when attaching cable tangent to a pole. Select and place cable blocks and corner blocks so as not to exceed the cable’s minimum bending radius. Do not pull cable across J -hooks. Store 100 f eet of each fiber -optic cable on all cable runs that are continuous without splices as shown on the plans . Obtain approval for spare cable storage locations. Store spare fiber - optic cable on fiber -optic cable storage racks (snow shoes). Locate spare cable storage in the middle of spans between termination points. Do not store spare fiber -optic cable over the roadway or driveways. Install one communications cable identification marker within 36 inches of pole attachment points and at locations where more than one cable originates or terminates.
C.Underground Installation Install fiber -optic cable underground in conduit using cable pulling lubricants recommended by the fiber -optic cable manufacturer. Obtain approval of cable pulling lubricant and method of pull ing before installing underground fiber -optic cable. Use a dynamometer (clutch device) so as not to exceed maximum allowable pulling tension if cable is pulled by mechanical means. Do not use a motorized vehicle to generate cable pulling forces. Keep tens ion on cable reel and pulling line at start of each pull. Do not release tension if pulling operation is halted. Restart pulling operation by gradually increasing tension until cable is in motion. For pulling cable through manholes, junction boxes and vaults, feed cable by manually rotating the reel. Do not pull cable through intermediate junction boxes, handhol es or openings in conduit unless otherwise approved by the Engineer . Install communications cable identification markers on each communications cable entering a junction box.
D.Installation of Drop Cable Assembly Determine length of drop cable needed, including slack, to reach from termination point to
Source: North Carolina Standard Specifications for Roads and Structures, 2024 Edition. Pages 820–821 of 857.