Perle Systems CM-110-XXXXX - Manual (Page 16)

Perle 10/100 Media Converter Module – Installation Guide 16
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.