Tip of the Week – 24 Feb 2011

Tip of the Week: The most common problem I encounter when debugging a fiber network is high fiber link loss due to dirty or damaged fiber connections. Fiber connection methods currently being used are mechanical connector, fusion splice, and mechanical splice. The most problematic one is the mechanical connector.  It uses an adapter (also known as a barrow) to connected two male fiber connectors together.  Three common and good quality single mode fiber connector types are LC, SC, FC.  They have a specified maximum insertion loss (IL) of less than 0.5 dB and often less than 0.25 dB, if they are clean.  A dirty fiber connection can increase the IL dramatically and impair communications.  It also can increase reflected optical power (ORL) back into the laser source which can cause laser instability (high BER) and in severe cases damage the laser.  Cleaning fiber connectors properly is an important task to be completed before all connector matings. Stay away from the ST connector type for single mode fiber, it is designed to be used only with multi-mode fiber.  Also, the Biconic connector is a very old connector type and is terrible.  It should be replaced if you still have it in your network. If you do not need to use a fiber connector, then it is best to fusion splice the two fiber ends together for best reliability and lowest IL.  Fusion splice IL is typically less than 0.1 dB and often is lower than 0.05 dB. Mechanical splice connections are sometimes used for temporary quick fiber connections or emergency fiber restoration, if the fusion splice crew cannot get to the location quickly.  They are small, easy to use, relatively inexpensive, and do not require expensive termination equipment.  They can easily be included in a restoration kit along with a fiber clever and stripping tools.
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Contact us for more details and pricing.  To view our products and services, surf to http://www.TelecomEngineering.com/products.htm To learn more about this topic and other fiber optic network topics, refer to my following books (publisher McGraw-Hill): Did you miss last week’s Tip?  If so feel free to peruse this month’s archived Tips at https://www.telecomengineering.com/About_us/Tip_of_week/tipofweek.htm Contacts: For information about our products and pricing contact us at toll free 1-888-250-1562 . If you have any questions regarding this tip or other fiber networking concerns, please feel free to email me at BChomycz@TelecomEngineering.com. To unsubscribe from this email newsletter Click Here or reply to this email and in subject line place “Unsubscribe”. To add a new subscription to this email newsletter Click Here or reply to this email and in subject line place “Subscribe”. Bob Chomycz, P.Eng. President Telecom Engineering Toll Free:  1.888.250.1562   www.TelecomEngineering.com The contents of this email is protected by copyright law and is intended for the private use of the designated individual named above. Unauthorized distribution and/or publishing of this content is prohibited. The information in this email is intended as a general guideline only and is not to be used in actual network engineering design.  Please contact us for proper design values for your network.