Fiber optic fusion splicing in the network project is a very important link to reduce fusion loss is every project construction personnel need to consider, the following methods can be in the project to avoid the occurrence of failure and reduce fiber fusion loss.
1. Consistent fiber brand
A line as far as possible using the same batch of high-quality brand-name bare fiber for the same batch of optical fiber, its mode field diameter is basically the same, the fiber in a point of disconnection, between the two ends of the mode field diameter can be considered the same, and thus in this disconnection point fusion can make the mode field diameter of the fiber fusion loss to a minimum. So require the cable manufacturer with the same batch of bare fiber, according to the requirements of the cable length continuous production, in each tray on the sequential numbering and clear A, B end, no jump number. Laying fiber optic cable shall be placed according to the number along the determined routing order, and to ensure that the B end of the previous tray of fiber optic cable to be connected to the A end of the next tray of fiber optic cable, so as to ensure that the splice can be fused at the disconnection point, and to minimize the fusion loss value.
2. Multiple construction, to prevent folding and twisting
Fiber optic cable erection in accordance with the requirements of the cable laying construction, cable is strictly prohibited to play a small circle and fold, distortion, long-distance fiber optic need more than one person at the same time, and equipped with 6 to 8 walkie-talkies, in addition to "front walk, cable on the shoulder" method of cable release, can effectively prevent the occurrence of back buckle. Traction force does not exceed 80% of the cable allowed, the maximum instantaneous traction force does not exceed 100%, the traction force should be added to the reinforcement of the cable. Laying fiber optic cable should be strictly in accordance with the requirements of fiber optic cable construction, so as to minimize the chances of fiber optic cable construction damage, to avoid damage to the fiber core caused by increased fusion loss.
3. Standard fusion splicing
Select experienced and well-trained fiber optic splicers for splicing, but the level of splicers directly affects the size of the splicing loss. Splicing personnel should be in strict accordance with the fiber optic fusion process flow chart for splicing, and the fusion process should be fused while testing the splicing loss of the fusion point with OTDR. Does not meet the requirements should be re-fused, the fusion loss value of the larger points, the number of repeated fusion to 3 to 4 times is appropriate, multiple fiber fusion loss are larger, you can cut a section of the cable to reopen the cable fusion.
4. fusion splicing environment
Splicing fiber optic cable should be in a clean environment is strictly prohibited in the dusty and humid environment in the open air, cable splicing parts and tools, materials should be kept clean, do not let the fiber connector moisture, ready to cut the fiber must be clean, no dirt. After cutting the fiber must not be exposed to the air for too long, especially in a dusty and humid environment.
5. Fusion splicing process
Choose a high precision fiber end cutter to prepare the fiber end face, the fiber end face is good or bad directly affects the size of the fusion loss, cutting the fiber should be a flat mirror, no burrs, no defects. Fiber end face axis inclination should be less than 1 degree, high precision fiber end face cutter not only improve the success rate of fiber cutting, but also can improve the quality of fiber end face. This is particularly important for OTDR test not fusion point (i.e. OTDR test blind spot) and fiber maintenance and repair.
6. The standard use of fusion splicer
Fusion splicer should be used correctly, the function of the fusion splicer is to fuse two fibers together, so the correct use of fusion splicer is also an important measure to reduce fiber splicing loss. According to the fiber type correctly and reasonably set the fusion parameters, pre-discharge current, time and main discharge current, main discharge time, etc., and in use and after the use of timely removal of dust in the fusion splicer, especially the clamps, each mirror and v-slot dust and fiber debris removal.
Each time before use should make the fusion splicer in the fusion environment for at least fifteen minutes, especially in the place of placement and use of environmental differences (such as winter indoor and outdoor), according to the prevailing air pressure, temperature, humidity and other environmental conditions, reset the fusion splicer discharge voltage and discharge position, as well as the v-slot driver reset and other adjustments.
