To Help Ensure Accurate RL Measurements, Use OTDR

To measure Return Loss, some means of isolating the connector part of the reflected signal is required: a mandrel wrap, index matching gel, or Optical Time Domain Reflectometer (OTDR).

1. A mandrel wrap is impossible to use with thick cables– Early instruments relied on using a mandrel wrap to choke off further reflections.This referencing works well enough for thin, single-fiber jumpers, but thicker multi-fiber cables cannot be mandrel wrapped tightly enough to be effective.
2. Gel is difficult with many connector types– Index matching gel works for simple cables, but it's difficult for complex connectors such as MTP/MPO male or Lemo.Plus, this method is messy and requires cleaning time.
3. Today, OTDR is the universally preferred method to measure Return Loss– Any sort of cable/connector can be accurately measured using an OTDR, provided the device under test is not too short (~0.5um).

READ THE BLOG:How to Accurately Measure IL/RL

Additional resources from the FOC team include:

• Category Resource
  • FOC Test Page
• View the Glossary,Acronyms,Military Specifications for Connectors
• Q&A Resource: email technical questions toAskFOC@www.spnnc.com

Have questions about this FOC Tip?

Contact FOC with questions at: (800) 473-4237 / 508-992-6464 or email:FiberOpticCenter@www.spnnc.comand we will respond ASAP.