EuroWire January 2017

Technical article

6 References 1 IEC 60794-1-22 Optical fibre cables – Part 1-22: Generic specification – Basic optical cable test procedures – Environmental test methods 2 IEC 60794-5-10 Optical fibre cables – Part 5–10: Outdoor microduct optical fibre cables, microducts and protected microducts for installation by blowing Paper courtesy of the 64 th IWCS Technical Symposium, Atlanta, Georgia, USA, October 2015.

▲ ▲ Figure 5 : Water frozen around end caps

values at -40°C, at 1,310nm and 1,550nm wavelengths respectively. After the test, attenuation changes of all fibres are really small and no visual damage to the cable sheath has been found. ▲ ▲ Figure 6 : OTDR graphs of the fibre with the largest attenuation values at -40ºC during the end cap test 5 Conclusion When micro-duct cables are used in cold areas, the influence of freezing condition on optical fibre transmission should be taken into consideration. In order to study this subject, two experiments are designed to evaluate such influence. Based on the test results in this paper, it can be concluded that the effects of frozen water on micro-duct air-blown cables are insignificant. However, the long-term effect during the cable lifetime should be also considered and further investigated. Thus, protective measures to avoid the penetration of water into micro-ducts should not be ignored. n air-blown

Yunfang Ruan, Zhuang Xiong, Xiaoli Liu, Wenjing Ye

State Key Laboratory of Optical Fibre and Cable Manufacture Technology, Yangtze Optical Fibre and Cable Joint Stock Co Ltd, and Huawei Technologies Co Ltd Shenzhen, Guangdong, China

Wuhan, Hubei, China Tel : +86 27 67887520 Email : xiongzhuang@yofc.com

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January 2017