The loss of a splice is shown by the lower trace of the fiber after it and the amount of that drop is the loss of the splice. Hint: A loss without reflectance can also be caused by stress on the cable, for example a kink in the cable or a fiber pinched in a splice . The Optical Time Domain Reflectometer (OTDR) is useful for testing the integrity of fiber optic cables. It can verify splice loss, measure length and find faults. Later, comparisons can be made. OTDR settings are a balance between dynamic range, acquisition time, spatial resolution and accuracy. To minimize testing time, compromises must be made on accuracy (detecting low loss. Splicing is required to create a continuous path for light transmission from one fiber to another. 1. Whether you're commissioning a new installation or diagnosing mysterious signal loss, an Optical Time Domain Reflectometer (OTDR) gives you a precise, visual map of every splice, bend, and break across the entire fiber run.