Unfortunately, fiber optic connectors have a terrible immune system and are highly susceptible to contamination or dirt. Getting into the habit of cleaning optical cables is a good way to ensure optimum system performances. Therefore, it is important to choose the right tools for cleaning and to know how to use them. This guide gives a brief overview of the general methods and safety precautions when cleaning fiber optic connectors but please be sure to follow the specific product manuals beforehand.
How do fiber optics become dirty?
Fiber optic connectors can become contaminated very easily, usually as a result of everyday activities. The main culprits are dust particles and oils. Fingertips can smudge oil onto fiber components and this can then catch dust against the fiber, resulting in scuffs to both the optic and the fiber connector. Merely inserting or removing a fiber can cause static that attracts dust particles and can lead to contamination. Even fiber caps can gather oil and dust and contaminate the fiber.
Why clean fiber optic connectors?
It is always important to maintain your equipment. Fiber optic connectors that become contaminated with dirt can reduce performance, cause link failure and ultimately be costly, so it is good to know that it is avoidable. Clean fiber optic components are essential for quality connections. Ultimately, a properly cleaned fiber optic cable can reduce contamination of the optical interface. For that reason, you should always clean connectors before mating, even when they are new.
Tools you will need
It’s important to use the right tools for cleaning and to know when is best to use them. At AudioVideoElectrical.com, we stock cleaning kits for fiber optics from many well-known brands, such as Chemtronics, Sticklers and CAIG Labs. Some are dry and some use cleaning solutions but all are good solutions when the directions are properly adhered to. For instance, Sticklers recommend using a residue-free and fast-drying solution such as in the video below. You could also use lint-free pads and isopropyl alcohol to wet-clean the connectors. You should clean and dry the end of the ferrule just before insertion. If you do plan to use a wet-cleaning tool, ensure that you use a dry lint-free pad, properly dry the connector off and examine it to be certain that it is clean. You can also use filtered compressed air or canned compressed air. For fibre optic connectors, there are two main kinds of cleaning instrument:
Reel cleaner for LC/SC type fibers
Reel cleaners have a refillable lint-free reel of cloth which moves after each cleaning session, meaning that there is always a clean surface. There are a multitude of reel cleaners that have each been designed to clean specific connectors, such as the one contained in the CAIG Labs K-FO79 Fiber Optic Cleaning Kit.
MPO/MTP connector cleaner
The MTP/MPO tool comes with a barrel on the end with the dual purpose of cleaning connectors and endpoints. Similar to the reel cleaner, it contains a refillable tape that can be used on both the fiber and the port. One such tool is the Senko SCK-SS-MPO Smart Cleaner. Optical cleaning kits such as the Camplex Neutrik OpticalCON and LC Fiber Optic Connector Cleaning Kit are also useful solutions when it comes to contaminated fibers. Be sure to follow the specific instructions for the cleaning kit you use.
Things you should always do
Be sure that laser sources are switched off before inspecting fiber connectors
Inspect the connectors before cleaning
Keep a cap on unplugged fiber connectors
Store unused protective caps in a sealed container to protect against dust and contamination
Use a pair of powder-free surgical gloves while handling fiber optic cables, as this can ensure cleanliness
What not to do
Never look into the end of an optical interface if the device is operational as laser radiation is harmful to and can potentially damage the human eye.
Don’t let the end of the fiber optic cable make contact with any surface, including your fingers.
Don’t bend the fiber cable, as this may result in internal breaks, leading to instability or diminished performance. Do not tip the can of CDA while blowing. Liquid may be released contaminating the surface of the fiber.
Never use alcohol or wet cleaning without a way to ensure that it does not leave residue on the endface. It can cause damage to the equipment.
Never use unfiltered handheld magnifiers or focusing optics to inspect fiber connectors.
Never reuse any tissue, swab or cleaning cassette reel.
Never use cotton swabs or cloth it will leave threads behind.
Never touch the clean area of a tissue, swab, or cleaning fabric.
Never touch any portion of a tissue or swab where alcohol was applied.
For a more comprehensive guide on the cleaning method for various fibre optic connectors, Cisco have created a useful manual.
To conclude, when done correctly, cleaning your fiber optic connectors is an easy and effective way of prolonging your equipment and ensuring optimum output. Now, go make sure that yours are sparkling clean!