MESSENGER CABLE -1 DESCRIPTION Furnish and install messenger cable (spanwire) with cable clamps , strandvise , machine bolts, eye bolts, 3 -bolt clamps, eye nuts, split- bolt connectors and all necessary h ardware. -2 MATERIAL Refer to Division 10. Item Section Grounding Electrodes 1091 -6 Messenger Cable 1098 -4 Pole Line Hardware 1098 -7 Wire 1091 -2 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. . -3 CONSTRUCTION METHODS Install g uy assemblies before installing messenger cable. Use 3/8 inch messenger cable for spans supporting vehicle signal heads and/or signs. Use 1/4 inch messenger cable for spans supporting only cables unless otherwise specified. For messenger cable crossing over railroad tracks, provide a minimum of 27 f eet of vertical clearance, unless otherwise specified. For permanent installations, install messenger cable in continuous lengths with no splices except where an insulator is required. With prior approval, existing messenger for temporary installations may be extended instead of installing new messenger cable. Tension messenger cable to eliminate appreciable sag and to match sag of surrounding utilities. Otherwise, allow 3 % to 4% sag of the span length between poles. For mid -run spans using wood poles, attach messenger cable to the pole with a 3 -bolt cable clamp with J -hook consisting of 5/8 inch diameter machine bolts, J -hooks, washers and square nuts to attach messenger cable to wood poles. Provide machine bolts that are 3 inches longer than the pole diameter. For mid -run spans using metal or other Department -approved poles, attach messenger cable to t he pole with a 3 -bolt clamp with J -hook secured to the metal pole via a pole band clamp. Refer to Metal Pole Standard Drawing Sheets in effect on the date of advertisement . When terminating spans at wood poles, connect messenger cable to a deadend strandvise attached to the pole via a 5/8 inch diameter shoulder eye bolt or 5/8 inch diameter shoulder angle bolt with 5/8 inch eye nut as shown in Roadway Standard Drawings . When terminating spans at metal or other Department -approved poles, connect messenger cable to a deadend strandvise attached to the pole via a pole attachment clamp. Refer to Metal Pole Standard Drawing Sheets as shown in the previous paragraph. Do not install more than one messenger cable and strandvise assembly to a single metal or othe r Department -approved pole attachment clamp. During installation, ensure that messenger cable is centered and directly aligned at the pole clamp’s attachment point such that the cable does not exert forces on the sides of the clamp’s attachment point. Maintain electrical continuity at all splices.
For messenger cable attached to joint use poles, install a new grounding system that complies with Article 1720 -3 for bonding messenger cable. If a pole ground e xists on the