When replacing the old copper cables of the monitoring system with optical fibers, a common misunderstanding is to rush to remove the old cables as soon as the new cables are connected. The safe sequence is to establish the backbone first, then partition the cutover points, and observe the old and new cables in parallel for a period of time before decommissioning the old cables. Do not pursue all-in-one replacement in the whole process.

First the trunk and then the branches

In the first stage, only the backbone link from the computer room to the aggregation point will be built: optical cable laying, termination, and testing will be completed before moving points to avoid backbone failure and empty terminals. The access end is divided according to point density: a small point with a single camera can be equipped with one optical and one electrical transceiver; the old analog site with 8 coaxial channels needs to be replaced with8-channel video + 1-channel reverse 485 data video optical transceiver, the PTZ control line comes back together with the main signal, no need to pull another control line. For stock points with only 100 Mbit capacity, you can first lead the optical fiber to the pole, and use100M single mode single fiber one optical one electrical fiber optic transceiverKeep the original camera connection method unchanged, and the transformation is divided into two steps.

Cutover will be done in batches based on the area, and the retention period will start from two weeks.

• One area is a cutover batch, and no more than ten points can be cut in a single night. The rollback drill must be completed within the window;
• After the new link goes online, the old copper cable will be kept in parallel for two weeks, covering day and night and at least one rainfall before re-evaluating the decommissioning;
• During the retention period, the light receiving power and picture status at both ends are compared every day, and points with a deterioration trend are rolled back and redone.

Before dismantling the old cable, two ledgers must be established

Dismantling old cables is the easiest step to disassemble: each cable on the old cable corresponds to a point and which connector box it falls on. You need to register clearly at one time. Record the fiber core number and port number of the new link on another table. Check the two tables point by point before you are allowed to start. On the day when the disassembly is completed, mark the removal status on the routing map. If you are not sure about the order, you can call EB-LINK 0755-83179002 to check the commonly used substitution combinations and batch divisions.