Frequently Asked Fiber Optic Cable Questions
Q. Are all fiber optic cable jackets permeable to water and water vapor?
A. Yes. Every cable outer jacket material and everything that is not hermetically sealed can, in fact, pass extremely small amounts of water molecules. Optical Cable Corporation's tight-buffered, tightbound fiber optic cable design confronts this potential problem head-on by protecting each individual fiber with a non-porous 900 micron buffer coating made from hard elastomers or high-performance PVC materials. This design effectively minimizes the presence of water molecules at the fiber's glass surface and eliminates potential embrittlement of the fiber in wet environments. Optical Cable Corporation's fiber optic cables are designed to be water tolerant and can function even if water molecules are present under the cable outer jacket.
For over 20 years, Optical Cable Corporation has led the industry developing and producing tight-buffered, tightbound fiber optic cables. These cables have been in use in many adverse, indoor/outdoor environments around the world with no failures reported due to damage from water or freezing water.
Q. What is a Core-Locked™ fiber optic cable and why is it important?
A. Some of Optical Cable Corporation's fiber optic cables feature a Core-Locked™ outer jacket that is pressure extruded over the interior cable structure. This jacket allows the cable to act as one mechanical unit and simplifies its installation because the pulling device (for example, Kellems® grips) is attached directly to the cable outer jacket.
The pulling forces on the cable outer jacket are directly transferred to the cable strength members with no slippage. In severe bends, the Core-Locked™ cable outer jacket keeps the cable elements in place, which retains the round shape of the cable, provides localized bend limits, and avoids wrinkling of the cable outer jacket. These effects combine to greatly enhance the survival of the cable if it is pulled over a sharp edge. This construction greatly resists tearing and prevents subsequent damage to the cable.
Optical Cable Corporation's B-Series and BX-Series Breakout Cables and G-Series and GX-Series Subgrouping Cables are manufactured with a Core-Locked™ pressure extruded outer jacket that fills the interstitial areas of the cable, which further reduces the voids under the cable outer jacket where moisture could otherwise accumulate. The tight Core-Locked™ outer jacket limits the volume of water to the point that expansion forces upon freezing are negligible and can cause no fiber or cable degradation.
Q. Are Optical Cable Corporation's Core-Locked™ fiber optic cable outer jackets difficult to remove for terminating?
A. No. All of Optical Cable Corporation's fiber optic cables are manufactured with an aramid yarn ripcord that easily opens up the cable outer jacket for removal of the interior elements. Some installers prefer to use an adjustable depth cable outer jacket removal tool instead of the internal ripcord on larger diameter cables or a coax-type stripping tool for smaller diameter cables. Of course, the installer should practice and set the proper depth of the tool on the end of the cable prior to entering the fiber optic cable mid-span. A local Optical Cable Corporation representative will be happy to demonstrate how this is done.
Q. Do Optical Cable Corporation's tight-buffered, tightbound Core-Locked™ fiber optic cables contain excess fiber lengths in them to facilitate tight radius bends and give high tensile strength?
A. Yes. Optical Cable Corporation's fiber optic cables are all helically stranded to insure no inner fibers are compressed or any outer fibers are strained. Optical Cable Corporation's fiber optic cables have approximately the same amount of excess fiber length as does a telephone-style loose-tube gel-filled fiber optic cable. Regarding tensile strength, Optical Cable Corporation's fiber optic cables generally have a two-to-one advantage in strength-to-weight ratio over a loose-tube gel-filled cable of an equal fiber count.
Q. What does it mean to have three-way protection in Optical Cable Corporation's Core-Locked™ fiber optic cables compared to loose-tube gel-filled fiber optic cables?
A. Optical Cable Corporation's fiber optic cables do not rely on an application of gel, made from petroleum or other chemicals, to protect the optical fibers under the cableouter jacket. Instead, Optical Cable Corporation applies a 900 micron buffer coating over each individual optical fiber for added strength and to prevent moisture intrusion. Individual subcable jackets are added as another layer of protection for the fiber. The ruggedized riser-rated PVC cable outer jacket gives a third layer of protection from water molecules, and makes the cable fungus-resistant and UV-resistant.
Loose-tube gel-filled fiber optic cable designs are based on historical copper cable designs developed when utility companies needed to find ways of extending the life of their copper cables, many with pulp insulation. Optical Cable Corporation was never in the business of manufacturing copper cables for the utility market. Instead, Optical Cable Corporation has always specialized in manufacturing the highest quality tight-buffered, tightbound fiber optic cables in the industry. Its technology is directly derived from military tactical cable development programs, which conclusively demonstrated that correctly designed tight-buffered fiber optic cables, using the proper materials, need no gel and are the only design suitable for survival in a military tactical field environment.
Q. At what temperature can Optical Cable Corporation's indoor/outdoor riser-rated fiber optic cables be used?
A. All of Optical Cable Corporation's B-Series and BX-Series Breakout Cables, D-Series and DX-Series Distribution Cables, and G-Series and GX-Series Subgrouping Cables have an operating temperature of -40°C to +85°C with minimal shift in attenuation when tested in accordance with TIA-455-3A and TIA-455-71.
Q. Why do Optical Cable Corporation's fiber optic cables cost less to install than loose-tube gel-filled fiber optic cables?
A. The cables cost less to install because of Optical Cable Corporation's tight-buffered, tightbound cable construction. The installer merely removes the cable's outer jacket and the subcable jackets to expose the 900 micron buffer coated optical fiber. After the buffer is stripped from the optical fiber, it can be directly terminated without any additional preparation. No breakout kits, no epoxy gel blocks, no messy gel removal, and no furcation tubes are required. Depending on the fiber optic cable type, connector type, and level of craftsmanship, an Optical Cable Corporation fiber optic cable can be 30% to 50% less expensive to terminate per connector than loose-tube gel-filled cables. This will typically yield a lower overall installed cost for a fiber optic cable installation. The higher the fiber count and shorter the link length, the greater the cost savings from using Optical Cable Corporation's fiber optic cables.
Q. Are there regulatory agencies with the mission of defining standards of network construction and which strive to ensure the safety of the consumer?
A. Yes. The two organizations established to provide regulatory functions are the National Electrical Code (NEC) and the Underwriters Laboratory (UL).
Optical Cable Corporation's riser-rated fiber optic cables are UL listed in accordance with NEC sections 770-51 (b) and 770-53 (b). Optical Cable Corporation's plenum-rated fiber optic cables are UL listed in accordance with NEC sections 770-51 (a) and 770-53(a).
Q. Are Optical Cable Corporation's fiber optic cables tested to specified standards of performance established by Bell Company Research (Bellcore) which is now Telcordia?
A. Yes. Bellcore was established and charged with the mission of providing research and development and establishing minimum standards for the Bell Telephone Company's infrastructure. It is specifically the research arm of the public telephone system in the United States. Bellcore has been changed to Telcordia™ Technologies. Telcordia™ does not establish the test procedures for these standards. The test procedures are provided by the TIA/EIA, specifically in the TIA/EIA 455 series of tests.
Optical Cable Corporation's fiber optic cables are tested to meet all of the applicable generic requirements outlined in GR-409-CORE for intra-building fiber optic cables. Optical Cable Corporation also offers an optional cable construction using polymer-coated aramid strength members that allow its cables to easily meet all applicable functional requirements of GR-20-CORE.