A main limitation of a passive DWDM or CWDM multiplexer system is its inability to provide system alarms, diagnostics and active monitoring of fiber signals.
Remote and local signal monitoring fiber ports can be added or ordered with many multiplexers. These ports are available on the receive and transmit network fibers providing a ~1% tap (-20dB down) signal. You would need to attach an appropriate optical spectrum analyzer or DWDM/CWDM power meter to see each channel power. Remote access DWDM/CWDM power meters are also available for this purpose.
If your current DWDM/CWDM mux does not have a monitor port an external one can be easily added. They add about 1.5 dB insertion loss into the fiber span.
Products
We now have available remote and local access DWDM and CWDM power meters that can be connected to passive DWDM/CWDM multiplexer monitor ports to view and monitor individual channel powers. We also carry external monitor ports that can be added to any DWDM or CWDM system. Please contact me if you are interested, 1.888.250.1562×4.
To learn more about this topic and other fiber optic network topics, refer to my following books (publisher McGraw-Hill):
“Planning Fiber Optic Networks”, ISBN 0-07-1499199 available from Amazon.com. Table of contents can be seen here: http://www.TelecomEngineering.com/products/resources/planningfibernetworks.htm.
Services
Telecom Engineering services include engineering, design, installation, testing, repair, 24x7 support and monitoring of fiber optic, wireless/WiFi and copper networks!