Fiber optic patch cords mainly include several types of fibers, such as OM1, OM2, OM3, OM4 multimode fibers and OS2 single-mode fibers, and the connector types also include SC, ST, FC, LC, MTRJ and E2000, etc. There is no fixed selection for these in practical applications, and it needs to be selected according to the actual interface situation of your engineering project equipment. How to choose the right fiber optic patch cord for your network? Just follow these steps:
Different connectors are used for different devices, and commonly used fiber optic patch cords include MPO, SC, FC, LC, and ST interfaces
MPO type fiber optic patch cord: Used for connecting 40G, 100G optical modules and high-density data centers;
LC type fiber optic patch cord: Used for connecting SFP optical modules, it adopts a modular slot, which is generally used on routers;
SC type fiber optic patch cord: Connect GBIC optical modules, its shell is rectangular, and the fastening method is plug-in door lock, which does not require rotation. It is generally used more on routers and switches;
FC type fiber optic patch cord: The external reinforcement method adopts a metal jacket, and the fastening method is a screw buckle, which is generally used more on the wiring rack;
ST type fiber optic patch cord: The shell is round, and the fastening method is a screw buckle, which is generally used more on the wiring rack.
Different grinding methods determine the quality of fiber optic transmission, and the colors of PC/UPC are blue, while APC is green.
PC is a micro-spherical grinding and polishing, and the plug surface is polished into a slight spherical shape. The fiber core is located at the highest point of the curve, which can effectively reduce the air gap between fiber components and make the two fiber end faces achieve physical contact.
The UPC connector end surface is not completely flat, but has a slight arc to achieve more accurate docking. UPC optimizes the end face polishing and surface smoothness on the basis of PC, and the end face looks more like a dome.
The fiber optic end face is usually polished into an 8° inclined plane. The 8° inclined plane makes the fiber optic end face tighter, and reflects light through its inclined angle to the cladding instead of returning directly to the light source, which provides better connection performance.
The typical insertion loss of PC, UPC, and APC connectors is less than 0.3dB. UPC/PC has a smaller air gap, making it easier to achieve low insertion loss. The return loss of PC is -45dB, the return loss of UPC is generally around 50dB (or even higher), and the industry standard return loss of APC is -60dB.
Fiber optic patch cords usually use PVC and LSZH materials.
PVC material is flammable and produces toxic gases, and is not suitable for indoor applications, but it is inexpensive.
LSZH (Low Smoke Zero Halogen) material has good environmental protection and flame retardant properties, but it is relatively expensive.
When selecting fiber optic patch cords, besides considering the actual length used, the reliability of the material should be also considered. Moreover, it is more important to pay attention to the transmission rate and loss of fiber optic. In the use of fiber optic patch cords, the plug core end face should be protected to prevent collisions. Remember to put on dust caps in a timely manner after disassembly. Do not look directly at the fiber optic end face when laser signals are transmitted.