EuroWire March 2023

Technical Article

IPA is not a good choice for cleaning modern fibre end faces. It is highly flammable and has a slower evaporation rate compared to the modern fluids engineered specifically for cleaning fibre optic connectors. IPA is also is hygroscopic and will attract contaminated water molecules from the atmosphere, re-depositing them onto the fibre end face. The water molecules in IPA will also slow the drying process, as it takes longer to evaporate from the end face. This not only affects cleaning time, but also adds to the probability that dust will migrate to the fibre. It is important to use high-quality, fast-drying, static-dissipative optical-grade cleaning fluid. Because it has been specifically engineered to clean fibre, it will not leave a residue on the end face or absorb moisture and contamination from the air. Its added benefit of being fast-drying means that the risk of contamination will be reduced and the installer can save time, as they do not need to wait for the fluid to dry. When using the cleaning fluid, do not oversaturate the wipe or cleaning tool. Too much fluid on the fibre increases the likelihood of re-contamination as it absorbs impurities from the air. It is important to choose a cleaning fluid in a package that delivers the cleaning fluid in metered doses. This will control the amount being used and ensure the surfaces are not too wet, allowing them to dry quickly after cleaning. Optical-grade wipes If using wipes to clean fibre, be sure to choose an optical-grade cleaning wipe. Paper wipes are inadequate as they rip and shred easily, leaving behind debris. They also generate high static charges, drawing in dust and making their use counterproductive. High-grade fabric wipes, engineered for cleaning fibre connectors and splices, are highly absorbent to effectively remove the contamination without generating lint. They are also designed to be soft enough not to scratch the end face. It is important to ensure the wipes are in sealed packages to keep them pure and clean prior to use and only opened when ready to wipe. When cleaning fibre, always inspect the termini on both ends of a connector pair first to visually identify the level of contamination. Then, using the wet/dry cleaning method, dispense the optical grade cleaning fluid onto a section of the cleaning wipe. Wipe the connector end face starting at the damp area and moving in one direction towards the dry area of the cleaning wipe. This removes the contamination and dissipates electro-static charges. It is important to use the wipe only once, to stop the risk of cross contaminating the network. Contamination from used wipes often re-deposits particulate or oils back onto the connector. This results in more time on the job or a costly call back. Sticks and click-to-clean tools The tools used to keep a fibre network clean can also be the cause of contamination. A good example is foam-tipped cleaning sticks.

Fibre optic networks are rapidly expanding into rural areas

These can leave lint and foam particles behind, making end faces even dirtier. A fabric-tipped cleaning stick designed specifically to match the configuration and size of the end face is a better alternative for optimal cleaning. Fibre cleaning sticks easily clean highly contaminated end faces when used with static-dissipating cleaning fluid and are perfect for cleaning connectors mounted in hard-to-clean alignment sleeves. Cleaning sticks effectively make contact with the structure of the end face, cleaning its entirety without disassembling the connector or adapter. As the stick cleans the surface, contaminants cannot migrate into the signal path. The cleaning fluid used with the stick also effectively creates a dissipative path to remove any static charge and threat of dust contamination prior to mating the connector. When using the stick, it is important to only rotate in one direction and only use one stick per end face to avoid cross contamination. Six rotations in one direction is enough to remove most contamination. Click-to-clean tools are best for end-face connectors with light to medium levels of contamination or for high-volumes of connectors like those found in data centres. They are quick and convenient to use and clean connectors with variable geometries. It is important to use high-quality click-to-clean tools correctly. A static charge can come from clicking a mechanical cleaning tool too many times in quick succession. This results in static charge building up with no place to dissipate, resulting in dust particulate sticking to the end face.

A new touch-less end-face cleaner is making its way to market specifically designed for FTTH, FTTA and data centre applications

Wear debris gets trapped inside the protective dust plugs that cover new cable end faces after manufacture

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March 2023