Can Multi-mode Fiber Patch Cords work in a Single-mode installation?

Multi-mode has a larger core than the Single-mode, 50 to 100 microns. Its light is much more bulky and because of this, light-waves are dispersed in numerous ways through the cable. This won’t be a problem for short distances, however in distances greater than 1 kilometer this can cause a light distortion at the far end resulting in incomplete data transmission.

What if you have to connect Multi-mode and Single-mode? Even though, installing a Multi-mode on a Single-mode transceiver is possible, it is highly advisable to use compatible equipment. When trying to mix up the installation it’s highly advisable to pay attention to the device’s specifications which can be found in the device’s datasheet.

When trying to install a Multi- mode Fiber on a Single- mode installation the main thing to keep in mind is to use a Mode Conditioning Patch Cable. This cable is designed and developed to provide a convenient method to connect a Multi- mode Fiber cables with 1000BASE-LX optical modules. Mode Conditioning cables provide the option to calibrate the Multi- mode Fibers with the Single- mode single core modules. They are built in the form of a duplex patch cords so there is no need of any additional components. The need for this kind of a patch cord is the default nature of the 1000BASE-LX modules to launch light of 1310nm down a single optical fiber. If Mode Conditioning Patch Cables are not used, and instead a normal Multi- mode Fiber is used with a Single- mode Transceiver module, the Single- mode Transceiver module will launch the light directly in the center of the cable, causing multiple light signals to be generated thus confusing the receiving module. A Mode Conditioning Patch Cable eliminates this issue allowing the Single- mode launch to be offset away from the center of the multimode fiber. This solution provides a launch similar to typical LED launches. While installing a Multi- mode Fiber onto a Single- mode module is possible, the other way around is not possible due to the bigger light wave of the Multi-mode modules, typically 62.5 microns, which is fired into a 9 microns fiber. This will result in at least 85% of light loss.