Insertion loss is the immediate power reduction that occurs whenever two fiber segments are joined through connectors or splices. This loss arises from several issues at the junction, including minor core misalignment, a small gap between end faces, or an imperfect surface finish. This phenomenon is influenced by a multitude of factors, including material absorption, bending effects, and. To be able to judge whether a fiber optic cable plant is good, one does a insertion loss test with a light source and power meter and compares that to an estimate of what is a reasonable loss for that cable plant. Loss is. Fiber optic networks are celebrated for their speed and reliability, but even the best systems can encounter problems. This guide will walk you through diagnosing and resolving common.