Knowledge

Passing the transformation acceptance is only the starting point. Whether the maintenance team can independently locate link alarms determines the long-term effect. This article gives four daily actions of checking DDM optical power, segmented measurement, cleaning and spare parts management, which can be written directly into the inspection card.

The link acceptance is normal, but the attenuation increases after half a year of operation. The problem most likely lies in the laying process. This article explains the differences between armored and ordinary jumpers, the sections worthy of armoring, as well as bending radius and label management to reduce the cost of later inspections.

Dispatch calls are uninterruptible voice channels. This article summarizes the key points of capacity inventory, grounding processing and power backup in the transformation of telecom optical terminals, helping to ensure that the connection is not lost during the transformation and that each phone can be independently verified after the transformation.

Communication equipment in outdoor cabinets must face high and low temperatures, DC power fluctuations, and dust condensation at the same time. This article gives the key points for selection from three aspects: wide temperature range check, DC power supply system, cabinet protection and wiring, so as to avoid selecting equipment based on indoor habits.

The bandwidth of the telecontrol channel is not large, but bit errors and delays are directly related to the reliability of the remote control. This article sorts out the key points of fiber optic design from three points: interface form, delay and optical power budget, and routing redundancy, for transformation designers to check one by one during the drawing review stage.

Ground potential differences and strong electromagnetic environments are common causes of damage to communication ports in substations. This article explains the principle of optical isolation transformation from three aspects: the conduction path of fault current, the insulation characteristics of optical fibers, and the division of priority optical channels, for reference in program review.

Whether the tunnel's electromechanical links are chain-shaped, point-to-point, or ring-shaped depends on whether operation and maintenance can tolerate single-point interruptions and whether the fiber core is sufficient. This article compares the applicable boundaries of several topologies and provides a set of loss budget steps from luminous power to receiving margin to help select the right gear based on distance.

Variable information boards and vehicle detector control lines are laid along tunnels and openings, and are susceptible to interference from lightning strikes and fan contactors. This article talks about how to do surge protection, photoelectric isolation and single-ended grounding when reverse 485 glazing, to help operation and maintenance prevent bus garbled and port burnout from these two stubborn problems.

There are emergency telephones at every other section of the tunnel, and they share the same optical cable with cameras and detection data, but each occupy its own fiber core. This article talks about how the emergency telephone optical transceiver is used for splitting and carrying the video and data links, and what should be paid attention to in the power supply and dispatch side connection method to avoid the three types of services being crowded on the same core.

The journey from the outer box of the tunnel to the management office or substation is often several kilometers, and signals must be picked up and dropped at various points along the way. This article explains how to determine the number of cascade layers of optical transceivers, how to calculate loss and power budget, and the choice between centralized power supply and nearby power extraction, to help operators design long links stably at one time.