Perle Systems C-110-XXXXX, CM-110-XXXXX manual Method

Method 2:

The fiber connection can also be verified by configuring the remote Media Converter for loopback mode. The LKF LEDs on both Media Converters should be lit. Data should pass through the local converter, over the fiber connection to the remote Media Converter. At the remote Media Converter, the data will be looped back and passed through the fiber, once again, to pass through the local converter to the copper link.

Note: If troubleshooting a CM-110, setting the Auto-Config jumper (J6) to SW will ensure the DIP switches are being read.

16 Perle 10/100 Media Converter Module – Installation Guide