First, using the OPM, check the input power level of the splitter. These are known as passive optical splitters, and they perform the function of splitting the light signal without using any power. Splitters are essential when you want one fiber line from a central office (like an ISP's headend or data center) to serve multiple homes or businesses. Insertion loss testing of the optical splitter is very important to ensure compliance to the optical parameters of the manufactured. Fiber optic splitters distribute optical power from one input fiber to multiple output fibers through either fused biconical taper (FBT) coupling or planar lightwave circuit (PLC) waveguide structures. Connector Inspection & Cleaning 6. Remediation &. This guide will equip you with a systematic approach to diagnosing and resolving the most common optical link performance issues. Before diving into troubleshooting, you must know.