〉〉New Products

Ultra-High Fiber Count Optical Fiber Cable Compatible
With European CPR
1.

Optical fiber

INTRODUCTION

With the recent increase in data traffic, networks are
becoming larger and larger in capacity through the development of optical fiber cable networks and data centers.
This product has been developed mainly for use aroundand inside data centers, and has an ultra-high fiber countstructure achieved by using intermittently bonded ribbon
fibers (Rollable ribbon), and also has features such as
high flame resistance and low smoke generation thatcomply with the European Construction ProductsRegulation (CPR). In addition, it has high mechanicalproperties and environmental resistance equivalent or
superior to conventional products, making it an effective
solution for both indoor and outdoor applications regardless of the environment in which it is used.

2.

Bonding portion

Flat state when removed from the cable core

FEATURES OF ROLLABLE RIBBONSIn order to realize an ultra-high fiber count structure that
accommodates more optical fibers in a cable, this product uses rollable ribbons as shown in Figure 1. Unlike theconventional ribbon fiber structure in which adjacent optical fibers are continuously fixed with adhesive resin, therollable ribbons are intermittently bonded to each other,allowing the shape of the ribbon fibers to be easily
deformed and the ultra-high fiber count structure to beachieved by storing them densely inside the cable. On
the other hand, when removed from the cable, it has thesame flat structure as conventional ribbon fibers, soworkability, such as multi-fiber batch fusion splicing, etc.
is equivalent to that of the conventional ribbon fibers.

Deformed state in the cable
Figure 13.

Structure and features of the rollable ribbon.

ULTRA-HIGH FIBER COUNT OPTICALFIBER CABLE COMPATIBLE WITH THE
EUROPEAN CPR

Figure 2 shows the structure of the 3456 fiber cable as an
example of this product. 12 rollable ribbon fibers consisting of 12 optical fibers are bundled together to form a 144fiber unit, and 24 of these 144 fiber units are placed in thecenter of the cable. The surrounding area is covered witha protection tape to ensure various cable characteristics,

Flame retardant sheathProtection tapeTension member
Optical ﬁber
Rip cord

Figure 2An example of the 3456 fiber cable.

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Ultra-High Fiber Count Optical Fiber Cable Compatible With European CPR

and a flame-retardant outer sheath with tension members
and rip cords arranged within the cross section areapplied.
Table 1 shows the characteristics of the 3456 fibercable. Various combustion characteristics in accordancewith the European CPR show a high flame resistance anda low smoke generation and when used indoors, even if afire should occur, the effects of the cable member combustion can be minimized.
Table 1Example of the cable performances (3456 fiber cable).

Characteristics and evaluation conditions

Evaluation results

Cable diameter

Approx. 25 mm

Cable weight

Approx. 580 g/m

CPR certified grade

Cca/s1b/a1/d0

Measured @1310 nm< 0.40 dB/km

Measured @1550 nm< 0.30 dB/km

Repeated bending

10 times the radius ofcable outer diameter< 0.10 dB/km

Compressive strength

2200 N/100 mm< 0.15 dB/km

Attenuation

Impact resistance

1.0 kgf, 1 m< 0.15 dB/km

Temperature cycling–30 - +70℃

< 0.15 dB/km

4.

CONCLUSION

This product has an ultra-high fiber count structure thatuses the rollable ribbon fiber technology. It has features
such as high flame resistance and low smoke generationthat comply with the European CPR, while at the sametime possesses mechanical properties and environmental
resistance equivalent or superior to those of conventional
products. These features allow the product to be usedboth indoors and outdoors, and it is expected to contribute to the construction of safer and more efficient opticalfiber networks, especially when applied around andinside data centers.
For more information, please contact:
Engineering Department,
Optical Fibers & Cables Division
TEL: +81-3-6281-8566
FAX: +81-3-6281-8639
Contact Form:
https://www.furukawa.co.jp/srm/form/index.php?id=enfttx• CPR certified grades are Cca: flammability, s1b: smoke emission,
a1: acidity of produced gas, d0: combusting droplets, respectively.
• Each mechanical property and temperature property are evaluated ata measurement wavelength of 1550 nm.

While possessing such a high flame resistance, thecable has mechanical and environmental resistance characteristics equivalent or superior to those of conventional
cable for outside use only, making it possible to use thecable for both indoor and outdoor use. This feature eliminates the need to install separate outdoor and indoor
cables, as has been the case in the past, and enables anefficient network construction with reduced cable installation and connection works by directly pulling cables fromoutside to inside the data center or directly connecting
multiple buildings on the data center campus.

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79