1. Construction excavation
Construction site excavation, drainage ditch digging after rain, municipal greening projects, and the excavation of heating and natural gas pipelines are the main reasons for cutting the pipeline. Within 1 km of the end, the entry point, the pole penetration point, the inside of the pipeline, and the bend point must be checked to avoid other break points and stretch points.
The ability to reach the fault site as quickly as possible is crucial for ensuring the repair's longevity. Once the construction crew cuts and fills the fiber optic cable, repairing the fault becomes extremely difficult.
If surrounding pipe manholes are buried or the pipes are damaged, determine a temporary route and extend the fiber optic cable for emergency on-site repair as soon as possible. The situation on-site is complex; if it's impossible to determine which plan is quick and effective, multiple plans will be implemented simultaneously if sufficient personnel are available. The availability of excavation tools, such as shovels and picks, is also a key factor limiting the repair time. To prevent the creation of new points of failure, mechanical excavation should be avoided on-site as much as possible.
Once troubleshooting is complete, a marking stone must be placed over the cut to protect the fiber optic cable splice box. There is no temporary safe route relocation, and personnel must be assigned to mark the site.
2. The vehicle hangs
If the fault point is on the other side of the road, emergency repair personnel should place a warning sign after arriving at the scene, designate a special person to direct traffic, protect the personal safety of emergency repair personnel during the repair process, and avoid secondary disruption of the optical cable during the repair process.
When dealing with a fiber optic cable sagging fault, you should first perform a bidirectional test on the fiber optic cable at the fault point using an OTDR and check the crossover poles, junction boxes, shims, etc., within the range of 3 to 5 poles at both ends of the break point to see if there is any fiber optic cable damage. Check for other points of damage and then address them accordingly.
When the vehicle is suspended, a pole and ladder should be prepared to temporarily support the fiber optic cable at the crosswalk. After the repair is complete, the crosswalk should be raised, the height adjusted, and the sign attached.
3. Fire
Optical cable failures caused by fires generally do not result in simultaneous service interruptions, and core-by-core disruption is typical of fire-related failures. After emergency repair personnel arrive on site, they will first assess the situation, extinguish the fire, and protect the damaged optical cable. Identifying the optical cables is a key challenge in repairing these failures. Upon arriving at the fault site, do not rush to cut the fiber optic cable's core, especially not multiple cores simultaneously. When cutting, mark both ends of the fiber optic cable to facilitate repair and soldering without reconnecting the wrong fiber optic cable.
This type of fault ensures that all high-temperature damaged optical cable segments are cut before soldering, to avoid reworking the damaged optical cable after soldering begins.
4. Hits the power pole
The fiber optic cable was severed because a construction vehicle struck the power pole. Upon arrival at the scene, install warning signs, cordon off the safety area for the emergency repair, assign personnel to instruct pedestrians, and conduct bidirectional testing on the fiber optic cable during the emergency repair to check for other break points. Once the repair is complete, the damaged pole should be replaced as soon as possible and repainted with warning paint.
When repairing this type of fault, pay attention to the use of an OTDR to perform bidirectional testing and check the locations where the poles, junction box, and spare pass within the 3-5 pole range at both ends of the break point to see if there is any damage to the optical cable. There are no other points of damage, which are then addressed specifically.
5. Theft and vandalism
Criminals maliciously cut or damage the fiber optic cable, causing it to become blocked. After this type of failure occurs, bidirectional testing of the fiber optic cable should be performed upon arrival at the scene. Failures caused by theft usually occur in remote areas, and with multiple cut points, they are easier to locate. When repairing, remember to check for other break points in the surrounding area. Begin resoldering and reinstall the fiber optic cable in a single step to avoid encountering break points after the soldering is complete.
The focus of troubleshooting damage caused by human error is on easily accessible points in the optical cable routing. Because some damaged optical cables are only partially severed, it is difficult to locate the fault points quickly. Organize on-site personnel to cooperate with testing personnel in the equipment room to locate the power cable's position using the power cable itself. After determining the power cable's position before and after the fault point (ideally within 100 meters), immediately lay the optical cable to replace the cut. Regardless of whether the damage was caused by theft or vandalism, the incident should be reported to the police as soon as possible.
6. Dog bites, rat bites, bird pecks, gunshot wounds, etc.
This type of failure is a low-probability event, and strengthening daily inspections and protecting the optical cable can prevent such failures. In the initial stage of such failures, most are single-core failures. When service is least affected, the affected core is first bypassed to restore service, and then the fault point is located and identified. Due to the difficulty of locating the fault, the optical fiber cable is usually repaired by replacement or cutting.
7. The core naturally breaks down due to aging
Since optical fiber is made from glass and plastic fibers, it is relatively fragile. In theory, static fatigue will occur over time, and the optical fiber will gradually age, leading to breakage of the natural fiber core. In actual use, however, few optical cable segments have a lifespan exceeding 15 years, so the probability of natural fiber core aging is low. Factors contributing to this include external damage to the optical cable, non-standardized splice box encapsulation, unqualified fiber splice discs, and poor splice quality.
When it comes to failures, the core is mainly restored and then the optical cable is repaired by replacing (repairing) the cut.
8. Natural disasters
Under the premise of ensuring personal safety, emergency repairs will be completed in the shortest possible time. In the event of large-scale natural disasters, widespread mobile phone communication disruptions are highly likely. Emergency repair personnel must be equipped with walkie-talkies or multi-operator mobile phones to ensure seamless communication throughout the emergency repair process.
Post time: Nov-18-2022
