1. Fiber Optics FIBER OPTIC CABLE CONSTRUCTION

2. Fiber Optics • We’ve already looked at the difference between SM and MM fiber and the core, cladding and buffer differences between them. • That is the preliminary composition of fiber. • The construction process adds strength members such as aramid yarn (Kevlar) and cable jacketing.

3. Fiber Optics • In some cases a fiber glass rod is added in the center of the cable assembly to maintain the proper bend radius. • If fiber is installed outdoors a metal sheath is added along with two layers of rigid jacketing and has a gel like material for moisture resistance.

4. Fiber Optics • All of these different construction types fall under one of three categories:

5. Fiber Optics • TIGHT BUFFERED: • These cables consist of several 900um fiber strands surrounded by strength members and bundled in a single jacket. • In some cases it is 900um fiber surrounded by aramid yarn and a jacket, i.e. simplex fiber

6. Fiber Optics • Some examples are: • Simplex 2. Zip cord/ patch cords • Distribution 4. Breakout • Distribution type fiber is the typical type of cable installed in today's backbones.

7. Fiber Optics • Tight buffered fiber used in the field DISTRIBUTION FIBER BREAK OUT FIBER PATCH CORDS TWO SIMPLEX CABLES

8. Fiber Optics • Currently fiber installs are done with MC type distribution fiber for todays backbones. • MC is a interlocking metal clad that surrounds the distribution style fiber, like the cables electricians use to wire commercial building lights.

9. Fiber Optics • This MC style cable is color coded to indicate the three types of fiber we install. • ORANGE = MM 62.5/125 • BLUE = OM3 50/125 • YELLOW = SM 8.3/125

10. Fiber Optics • By using this MC type we do not have to install conduit or inner-duct to protect the fiber backbone,therefore it is a labor saving solution, which is why it is so popular. • The challenge is removing the interlocking armor from the cable jacketing, this is done with a roto split tool.

11. Fiber Optics • LOOSE TUBE CABLES: • Loose tube cables consist of color coded tubes that contain either 6 or 12 strands. • All the tubes are surrounded by a strength member (aramid yarn), as well as a fiberglass bend radius rod and additional PVC cords to maintain the concentricity of the cable.

12. Fiber Optics • Loose tube fiber

13. Fiber Optics • All of this is then coated by a heavy duty outside jacketing. • Loose tube cables are typically used for OSP applications. • They also can have both MM and SM types of fiber in one cable assembly, remember that SM has a smaller buffer, that being the case the MM strands will also have the same size buffer.

14. Fiber Optics • Loose tube cables also contain a water proofing gel and may also contain icky-pic. • This gel requires hydrasol to clean and prep the cable for termination it is similar to citrus type cleaners.

15. Fiber Optics • RIBBON CABLE: • Ribbon cable is just as it sounds. Multiple strands of fiber are bonded together to form a flat ribbon. These ribbons can then be stacked to form multiple layers. • This type of fiber allows for very high counts that utilizes a small space. • Transatlantic / Transpacific applications

16. Fiber Optics • Ribbon fiber

17. Fiber Optics • Hybrid fiber is any fiber optic cable that has both SM and MM fibers, SM is always the first in the count. • For example if you are installing a 96 strand fiber the cable jacket will have the following information on it; SM 24/MM 72. • When terminating this cable the first 24 strands are single mode and the rest is multimode fiber.

18. Fiber Optics • Here is an example of a hybrid composite tight buffered fiber optic cable with the product description;

19. Fiber Optics • Fiber optic cables can be further classified as defined in NEC article 770.9 Types; • Nonconductive: These cables contain no metallic members and no other electrically conductive materials. • Conductive: These cables contain non current carrying conductive members such as metallic strength members, metallic vapor barriers, and metallic armor or sheath.

20. Fiber Optics • Composite: These cables contain optical fibers and current carrying electrical conductors, and shall be permitted to contain non current carrying conductive members such as metallic strength members and metallic vapor barriers. • In the code these cable designations are; • OFN (optical fiber non-conductive) • OFC (optical fiber conductive)

21. Fiber Optics • Composite fiber is OFC (optical fiber conductive).