What are the reasons for the failure of the communication optical cable line? The following are the four major reasons for analyzing the failure of communication optical cable lines. I hope to be helpful!
First: the impact of lightning
The armored parts of the optical cable are metal conductors. If there is a short circuit in the power line or a lightning strikes a metal part, a strong current will be generated, which will damage the optical cable line equipment, and may even cause serious casualties.
Two: Poor insulation of optical cable lines
If the insulation of the communication optical cable line is not good, the operating strength of the optical cable will be greatly reduced due to stress corrosion and static fatigue after the junction box is flooded or damp, and the optical cable will be broken in severe cases. .
Third: the influence of external forces
Line faults are usually caused by external forces. Since there are many communication optical cable lines laid in the field, the general burial standard is deep below the ground, so it is impossible to effectively avoid the damage of many external factors to the optical cable lines.
Four: Fault at the line joint
Faults are most likely to occur at line joints. This is because the optical fiber at the joint no longer has the ability to protect the original cable structure or the ability to protect has been significantly weakened. Therefore, the daily operation and protection work can only be carried out by the junction box. The probability of failure is greatly increased.
How to improve the accuracy of cable fault location?
With the support of national policies, a large number of optical cables have been laid and used, and their reliability and safety have attracted more and more attention. Relevant data show that about two-thirds of the main reasons for the interruption of optical fiber communication are caused by the failure of optical cable lines. In optical fiber communication, if the optical fiber is interrupted, we first consider the fault of the optical cable, and take certain positioning measures, first check the outside and then go to the transmission.
Let me share with you how to improve the accuracy of cable line fault location
Knowing how to use the instrument and mastering how to use the instrument is helpful for accurate measurement.
1. Set the parameters of OTDR
When using OTDR to test, the instrument parameters must be set first, the most important of which is to set the refractive index and test wavelength of the test fiber. Only by accurately setting the basic parameters of the test instrument can conditions be created for accurate testing.
2. Use the zoom function of the instrument
Using the zoom function of OTDR, the cursor can be accurately positioned on the corresponding inflection point, and the graph can be zoomed to 25 meters/div by using the zoom function key, so as to obtain more accurate test results, and the resolution is less than 1 meter.
3. Adjust the accurate test range file.
For different test range files, the distance resolution of OTDR test is different. When measuring fiber optic obstacle points, you should choose the test range file that is greater than the measured distance and the nearest test range file to make full use of the accuracy of the instrument itself for measurement.
Secondly, accurate and complete original documents should be established during the maintenance management process. These accurately completed optical cable line files are the basic basis for fault measurement and location. Therefore, in the process of maintenance and management, we should not be negligent, and we should establish true, credible and complete line information.
When monitoring the optical cable connection, record the cumulative length of the optical fiber from the test end to each connection point and the total attenuation value of the optical fiber in the connection section. At the same time, the model of the test instrument and the set value of the refractive index during the test are also registered. Accurately record all kinds of cable residues. Record in detail the winding lengths of optical cables at joint pits, special sections, S-shaped laying, room entry, etc., as well as the winding lengths of optical cables at splice boxes, junction boxes, ODF racks, etc., so as to deduct when the length of the fault point is converted.
In addition, the test conditions should be kept consistent during the measurement. During the obstacle test, the consistency of the test instrument model, operation method and instrument parameter setting should be ensured as much as possible to make the test results comparable.
