Fibre optics FAQs: the advantages, bend radius explained and more

Fibre optic cabling

What are fibre optical cables and what are they used for?

Today, all it takes is a seventh of a second to carry telephone calls and emails around the world – and that’s thanks to fibre optic cabling. Sending light beams via thin strands of plastic or glass, fibre optics allows them to bounce continuously off the walls.

Designed for long-distance and high-performance telecommunications and data networking, fibre optic cables provide a much higher bandwidth than wired cables. Supporting the world’s cable TV, telephone systems and Internet usage, they’re a vital component in the smooth running of our day-to-day tasks, including searching Google and tuning into our favourite shows.

To help you better understand the unique application of fibre optic cabling, here are the answers to seven common questions:

1. How does fibre optic cabling work?

Since we’re all used to the idea of information travelling in a host of ways, the concept and application of fibre optic cabling shouldn’t seem too surprising, owing to ever-evolving advancements in technology.

As we know, when we chat to someone through a landline phone, a wire cable carries the sounds from our voice into a wall socket; another cable then takes it to the local telephone exchange – and a perfectly audible phone conversation is made possible.

Mobile phones work differently. By sending and receiving information via invisible radio waves, they allow us to enjoy a wireless conversation on a device we can easily fit in our outstretched palm.

What about fibre optics? They work in a different way. Sending information coded in a beam light down a glass or plastic pipe, the technology was initially developed back in the 1950s, for use in endoscopes. The benefit of fibre optic cables is that – owing to them being made up of many strands of thin data – a greater number of wires can be merged into a single cable. This allows for much more efficient cabling.

Transporting communication signals via pulses of light generated by small lasers more commonly known as light-emitting diodes (LEDs), fibre optic cables are a modern-day phenomenon. To the centre of each strand of fibre optic glass is the ‘core’, which is the pathway on which the light travels. Surrounded by ‘cladding’ – a layer of glass which reflects the light inward to ensure loss of signal doesn’t occur – the light is able to freely pass through the cable’s bends.

2. How is fibre-optic cabling assembled?

Put together in a similar way to regular electric cabling, the fibre optic counterpart comes with its own unique management requirements – and that’s due to the fact the optic fibre s carry light, as opposed to electricity.

Prior to investing in a fibre optic cable assembly, manufacturers should consider the unique application of the fibre optics system.

Alongside its intended application, manufacturers should also ascertain the amount of data to be transmitted, as well as the potential future growth of the organisation. Other considerations include the existing fibre optic cable assemblies in use, as well as the financial resources available.

3. Why should I install fibre optic cable?

There are many reasons for laying fibre optic cable, with key advantages as follows:

  • With a higher capacity, fibre optic cables can carry a much larger bandwidth than a copper cable which similar thickness.
  • Reducing the need for signal boosters, light can travel for much longer, too, via a fibre cable – and it won’t lose its strength.
  • Less susceptible to interference, fibre cable is a preferable option. This is due to the fact that a standard network cable requires special shielding, which works to protect it from electromagnetic interference. Glass and fibre, however, manage to avoid these issues, thanks to their unique physical properties.

4. How many different varieties of fibre optic cable exist?

Singlemode, multimode and plastic optical fibre (POF) are the three types of fibre optic cable available, with each offering slightly different benefits. Singlemode optical fibre offers increased bandwidth capacity and a fast transmission speed, alongside limited external interference. Plus, the single input mode allows SMF to limit light scattering. This can reduce light weight, as well as increase transmission data.

Multimode fibre, like singlemode, offers high bandwidth at high speeds but is limited to shorter distances than singlemode.

Finally, plastic optical fibre performs at its best when used alongside visible red status indicator light services. What’s more, it tends to be more cost-effective than glass fibre cables, which means it’s more suitable for applications which require a consistent flexing of the fibre.

Check out this video that shows what industries require fibre management and why:

5. What is bend radius?

Bend radius is how sharply a cable can safely bend without causing damage by creating micro cracks on the glass fibres. Bending a fibre cable excessively can also cause the optical signal to refract and escape through the cladding. By interfering with light transmission, attenuation increases and compromises the integrity of the data being transmitted. Every cable will have a minimum radius, but this will vary according to the type being used.

Bend insensitive fibre can be either singlemode or multimode and is designed for better performance in reduced cable bend radius applications. Examples include residential or office buildings, or any space where tight bends and flexibility are needed, such a data centre server cabinet. Bend insensitive fibre has a refractive index trench, or a ring index of refraction material. This reflects the lost light caused by the bend so that it comes back into the fibre’s core, minimising data loss.

6. How do I calculate bend radius?

  • The manufacturer should specify the minimum radius that your cable may safely be bent.
  • When the manufacturer has failed to do this, you can go by this general rule of thumb:

The optical minimum bend radius is equal to ten times the outer jacket diameter of that cable.

So if you’re dealing with a fibre cable that has a 2mm outer jacket, then 2mm x 10 = 20mm bend radius.

 

This video explains the various material used in fibre management solutions:

7. What are my options for fibre optic cable protection?

Ensuring the correct fibre optic cable bend radius is just one form of protection.

Our video explains why you should consider these solutions:

This table shows the various fibre management solutions and their benefits to your applications:

Suggestions

Why

Fibre splice protectors

Maintain your cable’s strength and environmental stability

Corner fibre guides

Help with reeling your cable and maintaining a bending radius through a 90° turn

Wire saddles

Secure your fibre optic cables while protecting them from damage

Fibre bend limiting tubing

Protects cables from crushing, kinking and microbending – also a self-managing solution to routing

Strain relief bushings

Fibre strain relief glands protect against damage caused by rough-edged holes

Fibre optic connector boots

Strain relief for micron fibres while also providing protection during routing through holes

 

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Download free CADs and request free samples, which are available for most of our solutions. It’s a great way to ensure you’ve chosen exactly what you need. If you’re not quite sure which product will work best for your application, our experts are always happy to advise you. Whatever your requirements, you can depend on fast despatch.

Request your free samples or download free CADs now.

Questions?

Email us at sales@essentracomponents.co.uk or speak to one of our experts for further information on the ideal solution for your application 0345 528 0474.