Cables, such as telecommunication cables and electrical power distribution cables, are ubiquitous and used for distributing electrical power and all manner of data across vast networks. The majority of cables are electrically conductive cables (typically copper), although the use of optical fiber cables is growing rapidly in telecommunication systems as larger and larger amounts of data are transmitted. As cables are routed across power or data networks, it is necessary to periodically open the cable and splice or tap into the cable so that power or data may be distributed to other cables or “branches” of the network. The cable branches may be further distributed until the network reaches individual homes, businesses, offices, and so on. The cables of the distributed lines are often referred to as drop lines, branch lines, or distribution lines.
At each point where the cable is opened, it is necessary to provide some type of enclosure to protect the cable. Commonly, the enclosure has one or more entry ports through which cables enter the enclosure. Depending upon the number of entry ports in the enclosure, the sizes of the entry ports, the number of cables entering the enclosure, and the sizes of the cables, the number of cables passing through the each entry port will vary. Often, especially with smaller diameter cables as are typically used in distributed lines, multiple cables are bundled for placement into a single larger entry port. This is particularly common where multiple smaller cables are routed from a single point to multiple locations, such as individual homes, buildings, offices, etc.
At each entry port, no matter the number of cables passing therethrough, it is often desirable or necessary to provide a seal around the cables to prevent the ingress of moisture, dust, insects, and the like into the enclosure. Current methods of providing a seal around the cables typically involve bundling cables with mastic material or rubber tape. Such sealing methods are replete with disadvantages. The quality of the resulting seal is highly dependent upon the skill of the installer, and is therefore typically inconsistent from one installer to another installer. Further, as the number of cables increases, it becomes more and more difficult to form a reliable seal. The use of mastic or rubber tape to form a seal also presents difficulties when it is desired to re-enter the enclosure, so as to add or remove cables in the entry port. Specifically, the old sealing materials must be removed without damaging the cables, and a new seal must be constructed. The removal and reconstruction of the seal requires the use of additional time and materials, and therefore adds to the cost of maintaining or expanding the network.
To address the above-described disadvantages of mastic or rubber tape seals, there have been attempts to use pre-formed grommets to expand the capacity of entry ports in an enclosure. Typically, the grommets are sized to fit within an enclosure entry port, and have a predetermined number of holes for accepting smaller diameter cables. The cables are threaded through the holes in the grommet, and the grommet is in turn secured within the entry port. Such grommets have the disadvantage that the cables must have a free end to thread through the grommet openings. However, in many applications a free cable end is not available because the cable has already been connected, spliced or terminated. In such situations, to avoid disconnecting, re-splicing or re-terminating the cable, the installer typically cuts through the body of the grommet into the opening, using a utility knife or the like; such that the cable can be inserted lengthwise into the opening. Successfully cutting into the grommet in this manner is very dependent upon the skill of installer, and becomes increasingly difficult as the number of cables increases and as the size of the grommet and cables decreases. Further, the grommet is left with several cuts extending directly from the openings to the outer surface of the grommet. The cuts degrade the reliability of the grommet, and are a potential pathway for the ingress of moisture into the enclosure.
A need exists for a seal that enables an installer to consistently and reliably bundle multiple cables for placement into a single entry port of an enclosure, independent of the skill level of the installer. Furthermore, a need exists for a seal that can be easily and quickly installed, and that can be easily re-entered and re-used. Still further, a need exists for a such a seal that can also be installed on an existing cable, without disconnecting, re-splicing or re-terminating the cable.