Optical fibre has become the most advanced technology for high-speed data transmission, enabling ultra-fast and stable internet connections. However, there is a recurring myth that fibre optic cables are extremely fragile and can break just by bending them.
But how true is this, and is fibre optic fibre really so delicate that a simple bend could damage it? In this article, we will explore how fibre optics work, what happens when they bend and how we can prevent damage to your installation.
1. How do fibre optic cables work?
Before answering the main question, it is important to understand how fibre optics work. Unlike traditional copper cables, which transmit electrical signals, fibre optic cables use light to send data through glass or plastic filaments.
Each fibre optic cable is composed of several layers:
- Core: The centre of the cable, made of glass or plastic, through which the light travels.
- Cladding: Surrounds the core and helps keep light inside through a process called total internal reflection.
- Protective sheath: This is an outer layer that protects the cable against mechanical damage, moisture and dirt.
Thanks to this structure, fibre optics can transmit data at high speed and with less interference compared to copper cables.
2. Why can bending a fibre optic cable be a problem?
Although fibre optic cables have a certain flexibility, they cannot be bent every which way without consequences. Here’s why:
2.1. Signal loss due to radius of curvature
Every fibre optic cable has a safe bend limit, called the ” bend radius “. When a cable is bent beyond this point, light travelling inside the core can be deflected and escape, causing signal loss or attenuation.
In general, manufacturers indicate the minimum bend radius to be respected in order to avoid problems. In most cases, this radius is 10 times the cable diameter.
2.2. Possible core breakage
The fibre optic core is extremely thin and fragile. If bent too much, the glass or plastic inside the cable can break, causing complete signal disruption. This does not happen with a slight bend, but if the cable is repeatedly forced or bent sharply, the damage can be irreversible.
2.3. Invisible microfractures
Even if the cable continues to function after being bent, micro-fractures may develop in the core that are not immediately detected. Over time, these small cracks can expand and affect the quality of data transmission, causing speed drops or intermittent disconnections.
3. Are modern fibre optic cables more resistant?
As technology has advanced, so have the materials used in the manufacture of fibre optic cables. There are now cables designed to be more flexible and robust, such as Kevlar-reinforced fibre optic cables or bend-insensitive fibre (BIF) cables.
Estos cables pueden soportar dobleces más pronunciados sin pérdida de señal significativa. Sin embargo, incluso con estas mejoras, siempre es recomendable seguir buenas prácticas de instalación y evitar dobleces excesivos para garantizar un rendimiento óptimo.
4. How to prevent fibre optic cables from being damaged by kinking
If you have a fibre optic cable at home or in your company, here are some recommendations to avoid problems related to kinking:
4.1. Respect the minimum radius of curvature
Always check the cable specifications and make sure not to bend the cable beyond the recommended bend radius. As a general rule, avoid sharp bends and try to maintain a smooth bend.
4.2. Use cable guides and cable management
To prevent cables from being bent incorrectly, you can use cable organisers or guides designed specifically for fibre optic cables. This helps to keep the installation tidy and free of unnecessary strain.
4.3. Avoid stepping on or crushing cables
If the fibre optic cable runs along the floor or behind furniture, make sure it is not in a position where it can be stepped on or crushed, as this could damage it over time.
4.4. Do not coil cables incorrectly
If you need to coil a fibre optic cable, do so with a wide loop and no sharp bends. Avoid knotting or twisting, as this may affect its integrity.
4.5. Use fibre optic cables with reinforcement
If you need a more rugged cable, opt for reinforced fibre optic cables or bend-insensitive technology, which offer greater flexibility without affecting signal quality.
5. What to do if a fibre optic cable has been damaged by a kink?
If you suspect that your fibre optic cable has been damaged due to excessive bending, here are some actions you can take:
- Check the connection: If you experience a slowdown or frequent disconnections, check if the cable has been bent or pinched at any point.
- Try another cable: If you have access to another fibre optic cable, try temporarily replacing it to see if the problem is solved.
- Consult a technician: If the problem persists, it is best to contact a specialised technician to assess the condition of the cable and, if necessary, replace it.
6. Conclusion:Myth or reality?
The idea that fibre optic cables break with a simple bend is not entirely a myth, but neither is it an absolute exaggeration. Fibre optic cables have a safe bend limit that, if exceeded, can cause signal loss, micro-fractures or even total core breakage.
However, modern fibre optic cables have improved in strength and flexibility, allowing for safer handling as long as best installation practices are followed. If you have fibre optics at home or in your business, avoid extreme bending of cables and follow the recommendations to ensure a stable, high-speed connection.
