What if the optical fiber is accidentally broken during operation? This is common in the daily operation of weak current projects. Recently, some friends have asked this question.

If the optical fiber is broken, the two optical fiber lines should be connected together, which requires an optical fiber fusion machine. Because the optical fiber is made of quartz, it cannot be directly tied like a wire. At this time, it must use professional equipment worth thousands to tens of thousands of yuan to perform hot connection, but not all friends have optical fiber fusion machines.

One、 Cold connection of optical fiber

Is there any other way? Then you can only use the cold connection method!

The optical fiber is usually connected by three wires, but the real optical fiber is the one sandwiched in the middle. The main function of both sides is to protect the optical fiber in the middle. Because the optical fiber is very fragile and easy to break, it needs to be protected by a "bodyguard".

Sometimes, there may be two or three optical fibers in the middle, so we only need to use the blue one and break the other one.

Two、 Optical fiber cold joint steps

At present, the optical fiber enters the home with rubber cable, and the end is cold connector. The so-called cold joint is to peel the optical fiber, cut it, align it with the cold joint and fix it. The cold joint is more convenient, and no welding machine is needed.

The cold connection of optical fiber into the home mainly includes five steps: stripping, cleaning, cutting, cold connection and testing.

1. Stripping

Unscrew the cold sub tailpipe, and then put the optical fiber into the tailpipe

Peel off the PVC layer with a stripper, and cut the reinforcing rib at the same time.

Then use the smallest hole diameter of the fiber stripper to remove the coating

2. Cleaning

Clean the bare fiber with non-woven cloth dipped with absolute alcohol

3. Cut

Cut the optical fiber clamp together with the optical fiber on the clamp base of the optical fiber cutter

4. Cold connect the optical fiber into the cold connector body

5. Testing

Test the conduction state with an optical fiber test pen

6. The cold connection of optical fiber seems simple, but it is also a technical activity. There are also many precautions in the installation process:

A. During the whole installation process of connector, each link shall be clean

B. Ensure the quality of optical fiber cutting end face on site

C. The key to successful termination is the close fitting of the two ends of on-site optical fiber and embedded optical fiber

D. The length of the optical fiber cut on site should be accurate. The length of the optical fiber on site is not enough to contact the short optical fiber pre ground in the factory, which will lead to a gap between the end faces and increase the termination loss.

E. The length of the optical fiber cut on site shall be accurate, the fiber shall be threaded in place, the optical fiber shall be bent reasonably, and the two ends shall be provided with a tightening force to ensure end face contact. At the same time, the optical fiber shall not be too long, which may cause excessive end face pressure and damage to the optical fiber end face.

Three、 Difference between cold splicing and hot melting of optical fiber

1、 Hot-melt

The optical fiber fusion splicer and optical fiber cutter shall be used to connect the two optical fibers without other auxiliary materials. The advantages are stable quality, small connection loss (about 0.05 to 0.08db), and the disadvantages are high equipment cost, limited power storage capacity of equipment, and restrictions on field operations. In a word, the welding quality is good and the decay is low, but the operation is troublesome and requires a welding machine.

2、 Cold junction

It does not need too many equipment, but the optical fiber cutter can be used, but each contact needs a quick connector. The advantage is easy to operate, suitable for field operation, and the disadvantage is that the loss is relatively large. "About 0.2 to 0.5dB cold connector at each point", there is no choice in business and technical services, followed by the use of matching fluid in the cold connector. Due to less use and short time, aging problems need time to test.

In summary:

1. The cost of single cold welding is much higher than that of hot melting.

2. It is convenient to carry cold welding tools, while hot melting requires carrying a hot melting machine. Very inconvenient.

3. The loss of optical fiber after hot melting is low, and the loss of cold spliced optical fiber is relatively high.