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Technology - SHKE Cables Solution for Indoor

 

SHKE Cables Solution for Indoor

Introduction

FTTH networks require many different kinds of cables, because such networks cover indoor and outdoor sections, but also the transition in between. To fulfil these requirements outdoor, indoor-outdoor as well as indoor cable designs are necessary.
Another fact to be taken into consideration is that a huge variety of installation methods are in practical use, too. Commonly applied technologies are (micro-) duct and direct buried installation,aerial installation, but also on-wall, inside and outside  the buildings.In dependence of the local environment of the network the bestsuited installation methods are selected. Regarding this need cable designs should be suitable for as many as possible  installation technologies.
To address general requirements of fire protection  set by law orcustomers a HFFR jacket is mandatory. The best suited the HFFR grade is chosen according to the local requirements and fire test specifications to ensure the requested fire protection level.

SHKE cables  especially suited for indoor , where their capability to withstand bends with exceptional low radius without increase in attenuation is highly appreciated and offers superior advantages compared to standard SM fibers, since installation routes of indoor cables frequently pass areas where small bends occur, like around edges and corners. As an additional advantage the possible small bend radius allows reduced size connection equipment, like quite small splice closures and termination boxes.

Cable Design

For FTTH networks as described above no cable design is dedicated or preferred, neither for subscriber drop nor for indoor cables.Different approaches are suitable like central, loose or tight buffer tube constructions. Optional cable elements are tapes or yarns which may carry waterswellable materials in case a  dry design is desired. Possible other cable elements are strength members or copper conductors. The design is finally completed with a fire prevention sheath.

FTTH Drop Cable

The structure is 1-12 colored fibers combined with two FRP(or steel wires),which can protect the fiber inside by providing sufficint tensile strength and goodresistance to lateral crushing.Applications for indoor horizontal , vertiacal cabling ,indoor cable cabling under carpet and along corner.



Dry Tight Design

Dry tight designs with one or two fibers are dedicated to subscriber indoor branching. Therefore, such cables are mainly installed on-wall by stapling or gluing.The single fiber cable is a 2.8 mm diameter construction, the cable with two fibers a 4.2 mm diameter construction. Both are based on 900 um tight buffered fibers. In such a design the fiber is decoupled from the 900 mm buffer tube. This tight construction guarantees easy end-access of the optical fibers over one meter in less thana minute.



Riser Cable

When there is a need to get many fibers to several  distribution points or separate flats in different floors of a building, a riser design is chosen for the vertical installation. This cable has really low weight and size, something very important for a riser application. However, its main advantage in this case is the ability to segregate one or more bundles of fibers per flat, just by opening small windows of approximately 5 cm in length in the outer jacket.This could also allow termination of several fibers in a distribution box of a floor.The riser cable carries a maximum of 144 optical fibers with several small semi-tight buffer  tubes made of asoft material. These modules are loosely placed into the cable center, surrounded by some aramid yarns as strength elements.



Duplex Zipcord Cable

Basically, the zipcord cable consists of 2 patchcords of 2.8mm outer diameter each. Each one is made of 900µm tight buffered tube surrounded by aramid yarns and a LSZH/PVC jacket. The zipcord is splittable into the two single fiber patchcords.



Conclusions

Different types of FTTH subscriber drop, indoor and riser cables were successfully developed. They are approved by many customers for different applications. In parallel to the cables some customers approved bend optimized fibers to benefit from their superior low bending radii.The presented cables are suitable for all applications of FTTH subscriber drop, indoor and riser cables. The range of designs includes completely dry cables as well as designs with tight and tight buffer tubes and copper conductors.The presented cables offer a general range of FTTH cables,covering subscriber drop cables, indoor, indoor/outdoor applications as well as riser cables.