Should You Be Worried About Bending A Fiber Cable?

by www.fiber-mart.com

Fiber wires lose light no matter what. They have a db/km loss rate, this is subject matter we have covered in my other blog on Split Ratio & Budget Light Loss.

 

But, did you know your bend radius could affect the db loss of a fiber cable?

 

There is a lot of engineering, research and development that goes into building fiber network hardware. Today I’m talking about passive fiber network TAPs and the bend radius of a fiber cable.

 

Typical Electronic Frequency in HZ = is 1/ wavelength. In Fiber the Frequency (f) equation is the speed of light in fiber (v) /wavelength (A). The average speed of light in a fiber is around *2.14 X 10 -8 m/seconds.

 

Note this will cary with different fiber but is an acceptable average.

Frequency A is a higher frequency than frequency B which has a longer wavelengths.

An interesting fact – the frequency of a signal (light or photon flow) stays the same in the air or in a fiber.

 

Bend Loss Factors

Bend loss occurs when the fiber cable bends is tighter than the cable’s maximum bend tolerance. Bending loss can also occur on a smaller scale from such factors as:

 

Sharp curves of the fiber core

Displacements of a few millimeters or less, caused by buffer or jacket imperfections

Poor installation practice

 

Microbending: losses are due to microscopic fiber deformations in the core-cladding interface caused by induced pressure on the glass.

 

Macrobending: losses are due to physical bends in the fiber that are large in relation to fiber diameter. 

 

The signal still can get through but loss is still an issue – light is power. Light distortion = power loss. This hurts your optical budge.

 

In other words, if you have your fibers wrapped too tightly inside your network tools – you could be losing a lot more db than you thought, affecting the distance the data can travel with integrity.

 

Second, if the bend is too great, there will be stress placed on the cladding that may cause micro cracks, allowing leakage over time, as well as excess stress on the connectors, also causing misalignment that can cause further drops in db.

 

Our passive fiber TAPs have been designed and factory tested (read ‘Born in the USA: The Story of Garland Network TAPs’) eliminating any tight bend radius issues. We did not want to have a small compact design that would require tight fiber bends, increasing the risk of db loss as well as sharp curves that can occur in the manufacturing and assembly process.

 

Remember, don’t bend any fiber cable too much, or you may be creating errors on your network.