The common fiber optic loopback cable types are: SC, FC, LC and MT-RJ. Fiber optic loopbacks are with compact design, and they are compliant with fast Ethernet, fiber channel, ATM and Gigabit Ethernet. The fiber loopback modules can be with various jacket types and cable diameters, and they can be with different terminations and length. Sending a loopback test to network equipment, one at a time, is a technique for isolating a problem. Meet JIS5974 and bell core GR-326 standardįiber Loopback Patch Cord can provide a simple and effective means of testing, It is used to diagnose the problems of optical networking equipment. Zirconia sleeves or Phosphor bronze sleevesĪvailable without flanges or with flange for duplex, saving panel space Material Feature: PVC/LSZH/OFNR/OFNP/Plenum 2pcs Single Mode SC/UPC Fiber Optic Loopback Adapter Cable, Duplex SC Connectors Singlemode 9/125 Test Plug for Testing Applications. Insertion loss: SM: 1.2dB typical, 1.5dB max MM: 0.2dB typical, 0.7dB maxįiber Type: SM, MM, OM1, OM2, OM3, OM4, duplex, simplex The selection guide for some mostly used transceiver modules is summarized in the following tables.Connector Type: FC/SC/LC/ST/ MTRJ/ DIN/E2000 Which to Choose for a Specific Transceiver?Ĭonsidering the common features of the transceiver and the loopback, we should think about the connector type, polish type, and cable type when selecting a loopback for the transceiver. Its configuration varies since the fiber count is not always the same in different applications.

As for the MTP/MPO loopback, it is mainly used for testing parallel optics, such as 40G and 100G transceivers. The LC and SC loopbacks are made with simplex fiber cable and common connectors it’s not difficult to understand their configurations. In testing fiber optic transceiver modules, the most commonly used are LC, SC and MTP/MPO loopback cables. According to the optical connector type of the loopback, fiber loopback cables can be divided to LC, SC, FC, ST, MTP/MPO, E2000, etc. Based on the fiber type used, there is single-mode loopback and multimode loopback, available for different polishing types. This designing is more compact in size and stronger in use. Some vendors provide improved structure with a black enclosure to protect the optical cable. Generally, a fiber loopback is a simplex fiber optic cable terminated with two connectors on each end, forming a loop.

Before deciding which loopback cable to use, we should firstly know the structure and classification of fiber loopback cable.

Fiber loopback cable