Test Set

As light traverses a fiber, it decreases in power level. The decrease in power level, also called optical loss, is expressed in Decibels (dB). The most accurate way for fiber testers to measure the overall optical loss in a fiber is to inject a known level of light in one end and measure the level of light at the other end, using an OLTS. The difference between source and receive power levels is the loss. An optical loss test set is a hand-held field instrument used to perform specific tests for a fiber optic link or channel. These tests include measuring the length and optical loss, and checking the polarity of the installed fiber optic links.