Blog

Fusion vs. Mechanical Splicing
Unfortunately, damage to fiber optic connectors is common in FTTA installations. If a fiber connector is damaged, either a whole new cable can be pulled or the damaged connector can be replaced.

Fusion splicing is one method for attaching a pre-terminated fiber connector with a fiber stub (called a pigtail) to the broken fiber cable. The fusion process involves melting the glass at the fusion point so that a seamless joint is created. This joint is structurally weak and must be reinforced with a splice sleeve.

Fusion splicing is not recommended for tower repairs because the required equipment is expensive and requires a power source, making tower-top repairs difficult. Moreover, the tower hand must be trained in fusion splicing techniques.

A field-mount solution with an internal mechanical splice offers an alternative method for repairing a broken fiber connector. Field-mount connectors with a mechanical (as opposed to a fuse-on) splice are well-suited for FTTA repairs. They can be installed quickly and easily using an inexpensive hand tool, and tower hands can learn to use them with minimal training. Field-mount connectors carry a proven track record of success. More than 10 million of them are installed today in harsh and demanding applications around the world.

Testing
Some installation companies include fiber testing as part of the site build documentation. A general knowledge of the types of measurements and the test instruments used is also helpful for verifying a successful field termination for repair.

Two important fiber measurements are insertion loss and return loss. Both are measured in decibels (dB). Insertion loss measures how much light signal is lost as it travels through the fiber optic cable from end to end. Return loss measures how much light is reflected due to impairments (microbends, macrobends, damaged or improperly installed connectors, etc.) in the fiber.

An optical source and power meter measures insertion loss, and an optical time domain reflectometer (OTDR) locates sources of return loss. These instruments are available from TARLUZ and other test equipment suppliers.