The use of fiber optic cable

1. how to choose cable?

The choice of optical cable in addition to according to the number of fiber cores and fiber types, but also according to the use of optical cable environment to choose the structure of the optical cable and outer sheath.

1) When outdoor optical cable is directly buried, loose armored optical cable should be selected. When overhead, you can choose a loose cable with two or more reinforcement black PE outer sheath.

2) the optical cable used in the building should be used in the selection of tight sleeve optical cable and pay attention to the characteristics of flame retardant, poison and smoke. Generally, flame retardant but smoky type (Plenum) or combustible non-toxic type (LSZH) can be selected in pipes or forced ventilation, and flame retardant, non-toxic and smokeless type (Riser) should be selected in exposed environments.

3) the vertical or horizontal cable in the building, can be used with the building in the general tight-sleeve cable, cable distribution or branch cable.

4) according to the network application and optical cable application parameters to select single mode and multi-mode optical cable, usually indoor and short distance applications to multi-mode optical cable, outdoor and long distance applications to single mode optical cable.

2. How to choose different applications of fixed connection and active connection in optical fiber connection?

The active connection of optical fibers is realized by optical fiber connectors. An active connection point in an optical link is a clear segmentation interface. In the choice of active connection and fixed connection, the advantages of fixed connection are lower cost, less optical loss, but less flexibility, while active connection is the opposite. When designing the network, it is necessary to flexibly choose the use of activities and fixed connections according to the whole link situation, to ensure both flexibility and stability, so as to give full play to the advantages of each. The active connection interface is an important interface for testing, maintenance and change. Compared with the fixed connection, the active connection is relatively easy to find the fault point in the link, which increases the convenience of replacing the faulty device, thus improving the system maintenance and reducing the maintenance cost.

3. The optical fiber is getting closer to the user terminal. What are the significance of "optical fiber to desktop" and what factors should be paid attention to when designing the system?

In the application of the horizontal subsystem, the "fiber to the table" and the copper cable are complementary and indispensable. Optical fiber has its unique advantages, such as long transmission distance, stable transmission, not affected by electromagnetic interference, high support bandwidth, and no electromagnetic leakage. These characteristics make optical fiber play an irreplaceable role of copper cable in some specific environments:

1) When the transmission distance of information points is greater than 100m, copper cable is selected. The need to add Repeaters or network equipment and weak current rooms increases the cost and risk of failure, which can be easily addressed using fiber optics.

2), in the specific working environment (such as factories, hospitals, air conditioning room, power room, etc.) there are a large number of electromagnetic interference sources, fiber can be free from electromagnetic interference, stable operation in these environments.

3) Optical fiber does not exist electromagnetic leakage, it is very difficult to detect the signal transmitted in the optical fiber. It is a good choice in places with high secrecy requirements (such as military, R&D, auditing, government, etc.).

4) In the environment with high demand for bandwidth, up to 1G or more, optical fiber is a good choice.

The application of optical fiber is gradually extending from the trunk or the computer room to the desktop and residential users, which means that more and more users who do not know the characteristics of optical fiber start to contact the optical fiber system. Therefore, when designing an optical fiber link system and selecting products, you should fully consider the current and future application requirements of the system. Use compatible systems and products, which are as easy to maintain and manage as possible, and adapt to changing field conditions and user installation requirements.

4. Can fc connector be directly connected to sc connector?

Yes, it's just a different way of connecting two different types of connectors.

If you need to connect them, you must choose a hybrid adapter, using fc/sc adapters to connect the fc and sc connectors at each end. this method requires that the connectors should be flat ground. If you must connect inclined angle (apc) connectors, the second method of damage prevention must be used.

The second approach is to use a hybrid patch cord and two connection adaptors. Hybrid jumpers use different fiber connector types at each end, and these connectors will go where you need them, so that you can connect to the system using a common adapter in the wiring panel, but with the added amount of a connector pair to the system attenuation budget.

5. The fixed connection of optical fiber includes mechanical fiber connection and hot melt connection. What are the selection principles of mechanical fiber connection and hot melt connection?

Mechanical fiber connection is commonly known as fiber cold connection, which refers to the fiber connection method of single-core or multi-core fiber permanent connection through simple connection tools and mechanical connection technology without the need of hot melt bonding machine. In general, when connecting optical fibers with small core number and scattered locations, it is advisable to use mechanical connection instead of hot fusion.

The mechanical fiber connection technology was often used in the early engineering practice such as line repair and small-scale application on special occasions. In recent years, with the large-scale deployment of fiber to the desktop and Fiber to the Home (FTTH), people have realized the significance of mechanical fiber connection as an important means of fiber connection.

For fiber-to-desktop and fiber-to-home applications with large number of users and dispersed locations, when the scale of users reaches a certain level, the construction complexity and the construction personnel and fusing machine cannot meet the requirements of user opening service time. The mechanical optical fiber connection provides the most cost-effective optical fiber connection solution for large-scale optical fiber deployment due to its simple operation, short personnel training period, and small equipment investment. For example, the mechanical fiber connection provides a convenient, practical, fast and high-performance fiber connection method for the design, construction and maintenance personnel in the high and narrow space of the corridor, insufficient lighting and inconvenient on-site power extraction.