We know that fiber optic patch cables play a very important role in the connection between devices and equipment. When talking about fiber optic patch cables, we usually divide them into multimode fiber optic patch cables and singlemode fiber optic patch cables according to the modes of the cable. What is multimode fiber optic patch cable? How many types of multimode patch cables are there? And what is the difference between multimode and singlemode patch cables? What are the applications of multimode patch cables? This text will solve those questions one by one.
Multi-mode fiber patch cables are described by the diameters of their core and cladding. There are two different core sizes of multi-mode fiber patch cords: 50 microns and 62.5 microns. Both 62.5 microns and 50 microns patch cable feature the same glass cladding diameter of 125 microns. Thus, a 62.5/125µm multi-mode fiber patch cable has a 62.5µm core and a 125µm diameter cladding; and a 50/125µm multi-mode fiber patch cable has a 50µm core and a 125µm diameter cladding. The larger core of multi-mode fiber patch cords gathers more light and allows more signals to be transmitted, as shown below. Transmission of many modes of light down a multi-mode fiber patch cable simultaneously causes signals to weaken over time and therefore travel short distance.
Multimode fiber optic cables can be divided into OM1, OM2, OM3, and OM4 based on the types of multimode fiber. The letters “OM” stands for optical multimode. OM1 and OM2 belong to traditional multimode fiber patch cable, while OM3 and OM4 belong to the new generation fiber patch cable which provides sufficient bandwidth to support 10 Gigabit Ethernet up to 300 meters. The connector types include LC, FC, SC, ST, MU, E2000, MPO and so on. Different type of connector is available to different equipment and fiber optic cable.
By the materials of optic fiber cable jackets, multimode fiber patch cord can be divided into four different types, PVC, LSZH, plenum, and armored multimode patch cable. PVC is non-flame retardant, while the LSZH is flame retardant and low smoke zero halogen. Plenum is compartment or chamber to which one or more air ducts are connected and forms part of the air distribution system. Because plenum cables are routed through air circulation spaces, which contain very few fire barriers, they need to be coated in flame-retardant, low smoke materials. Armored fiber patch cable use rugged shell with aluminum armor and kevlar inside the jacket, and it is 10 times stronger than regular fiber patch cable.
Multimode and singlemode fiber optic patch cables are different mainly because they have different sizes of cores, which carry light to transmit data. Singlemode fiber optic patch cables have a core of 8 to 10 microns. Multimode fiber patch cable allows multiple beams of light passing through, while singlemode fiber cable allows a single beam of light passing through. As modal dispersion happens in multimode fiber cable, the transmission distance is relevantly nearer than singlemode fiber cables. Therefore, multimode fiber optic patch cable is generally used in relevantly recent regions network connections, while the singlemode fiber cable is often used in broader regions.
Multi-mode fiber patch cables are used to connect high speed and legacy networks like Gigabit Ethernet, Fast Ethernet and Ethernet. OM1 and OM2 cables are commonly used in premises applications supporting Ethernet rates of 10Mbps to 1Gbps, which are not suitable though for today’s higher-speed networks. OM3 and OM4 are best multimode options of today. For prevailing 10Gbps transmission speeds, OM3 is generally suitable for distance up to 300 meters, and OM4 is suitable for distance up to 550 meters.
Fiber optic patch cords are designed to interconnect or cross connect fiber networks within structured cabling systems. Typical fiber connector interfaces are SC, ST, and LC in either multimode or singlemode applications. Whether to choose a singlemode or multimode fiber patch cable, it all depends on applications that you need, transmission distance to be covered as well as the overall budget allowed.