Short fiber optic premises cabling networks are generally tested in three ways, connector inspection/cleaning with a microscope, insertion loss testing with a light source and power meter or optical loss test set, and polarity data, meaning that the routing of fibers . Short fiber optic premises cabling networks are generally tested in three ways, connector inspection/cleaning with a microscope, insertion loss testing with a light source and power meter or optical loss test set, and polarity data, meaning that the routing of fibers . 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. The estimate, called a "loss budget" is calculated using typical component losses for. The optical fiber fusion splicing technology mainly uses a fiber fusion machine to connect optical fibers and optical fibers or optical fibers and pigtails, and fuse the bare fibers and optical fiber pigtails in the optical cable together into a whole, while the pigtail has a separate optical fiber. If the pigtail is sufficiently long, 10 meters or so, VIAVI SolutionsTM Optical Time Domain Reflectometers (OTDRs) with pulses as short as 1 foot can perform these measurements. Depending upon their particular specifications and the actual distances involved, some instruments may or may not use. Fiber loss can be also called fiber optic attenuation or attenuation loss, which measures the amount of light loss between input and output. Factors causing fiber loss are various, such as intrinsic material absorption, bending, connector loss, etc. The losses are typically categorized. In the test report for a fiber cable, you may often see some data related to fiber insertion loss (IL) and return loss (RL), but do you know what insertion loss and return loss actually mean? How do the values of IL and RL impact the quality of the fiber cable? Are higher values better, or lower.