Issue link: https://www.e-digitaleditions.com/i/1192126
January/February/March 2020 I 39 1 2 1 4 2 3 1 2 9 10 3 4 11 12 6 5 8 7 1 6 2 3 4 5 7 2 Tube 4 Tube 7 Tube 12 Tube Date Issued: 03/18 Revision: 15 19 9 10 11 12 13 14 1 17 24 20 21 22 15 16 23 2 3 18 4 5 6 7 8 1 2 3 4 5 6 7 8 9 12 13 14 15 16 17 18 19 10 11 19 Tube 24 Tube FIGURE 4: Tube cable 2-to-24 configurations. Some customers leave tubes empty for future expansions and upgrades. Tube cables generally range from 2-to-24-tube cable options as shown in Figure 4. Tube distribution units (TDUs) are installed at strategic locations to connect the tube cable and can also be the point of transition to another branching location. At the TDU transition point, there are many applications that can be deployed, such as making nondisruptive moves, adds, and changes (MACs), distribut- ing from larger count tube cable to smaller counts and also transitioning through environments of differing cable jacket ratings, such as an out- side plant to riser or plenum. This transition is done by coupling tubes FIGURE 5: Tube cables are joined in the TDU using push-fit connectors. Splices, the most common site of network failure, are virtually eliminated allowing point-to-point connectivity in the network. FIGURE 6: The blowing equipment setup. together and allows for a continuous point-to-point and end-to-end fiber bundle blow without any fusion splicing, thereby eliminat- ing potential points of network failure (Figure 5). Once the complete (approximately 4,300 meters), and 48 and 72-strand up to 10,500 feet (approximately 3,200 meters). Once the tube cable is in place, the fiber bundles are then blown into the tubes using only two installers. The process of blowing the fiber is done using special blowing equipment and safe nitrogen gas or compressed air (Figure 6). infrastructure pathway is installed with the tube cable, a pressure test must be performed to ensure the integrity of the tubes as well as an obstruction test assuring that there is no possible obstruction. Single- mode (OS2) 2, 4, 6 and 12-strand can be ordered in lengths up to 39,000 feet (approximately 12,000 meters), 24-strand up to 14,500 feet