How to perform Optical Fiber fusion and testing?

How to perform Optical Fiber fusion and testing?

1. Optical Fiber Connection

(1) optical fiber connection. The principle of optical fiber connection should be followed: when the number of cores is equal, it must be connected to the corresponding colored optical fiber in the tube. If the number of cores is different, the number of cores is large first, and then the number of cores is small.

(2) optical fiber connection methods include splicing, active connection, and mechanical connection. Generally, the welding method is used in the project. Using this fusion method, the contact loss is small, the reflection loss is large, and the reliability is high.

(3) optical fiber connection process and steps:

① Enable or remove the optical cable and fix it in the connection box. Do not hurt the bundle tube. Take the length of about 1 MB for stripping. use toilet paper to wipe the oil paste clean and put the optical cable into the connecting box. When fixing the steel wire, compress the cables and do not loosen them. Otherwise, the fiber core may be broken by rolling the optical cable.

② Split the optical fiber through the heat shrinkable tube. Separate the optical fiber cables of different beams and colors and pass through the heat-shrinkable tube. The optical fiber that is stripped from the coating layer is very fragile. The heat-shrinkable tube can protect the optical fiber fusion connector.

③ Open the power supply of the Furukawa S176 melting machine, use 42 preset programs for welding, and remove dust from the melting machine in time after use and use, especially the jigs, dust and optical fiber fragments in mirrors and vswitches are not found. CATV adopts conventional single-mode optical fiber and dispersion-displacement single-mode optical fiber, and the working wavelength is 1310nm and 1550nm. Therefore, the appropriate fusion program should be selected based on the optical fiber used by the system and the working wavelength before splicing. If there are no special cases, the automatic weld program is generally used.

④ Create an optical fiber end face. The quality of optical fiber end faces will directly affect the connection quality. Therefore, a qualified end face must be prepared before splicing. The coating layer is peeled off with a special wire-stripping clamp, and then wiped several times on the bare fiber with alcohol-stained Cleaning Cotton. The intensity should be moderate, and then the optical fiber is cut with a precision optical fiber cutter to 0.25 (outer coating) optical fiber, cut length is 8mm-16mm, for 0.9mm (outer coating) optical fiber, cut length is only 16mm. After cutting, carefully place the optical fiber into the V-shaped Trough of the melting machine, close the wind shield, and press the discharge key of the melting machine to automatically complete the welding, which takes only 11 seconds.

6. Remove the optical fiber and use the heating furnace to heat the shrinking tube. Open the wind shield, remove the optical fiber from the melting machine, and then place the heat shrinkable tube in the center of bare fiber, and place it in the heating furnace for heating. The heater can use 20mm miniature heat shrinkable sleeve tubes and 40mm and 60mm general heat shrinkable sleeve tubes, 20mm heat shrinkable Tubes take 40 seconds, 60mm heat shrinkable Tubes are 85 seconds.

7. Fixed Disk fibers. Attach the attached Optical Fiber disk to the optical fiber receiving board. The larger the radius of the disc ring, the larger the radians, and the smaller the loss of the entire line. Therefore, we must keep a certain radius to avoid unnecessary losses when the laser is transmitted in the core.

The secret is sealed and suspended. The field connection box must be sealed to prevent water entry. After the melt box enters the water, the optical fiber and optical fiber fusion points may be soaked in water for a long time.

2. Optical Fiber Testing

After the optical fiber is set up, the test is performed after the fusion is completed. The main instruments used are the OTDR tester or the optical power meter, with the Canadian EXFO FTB-100B portable Chinese Color touch screen OTDR Tester (dynamic range of 32/31, 37.5/35, 40/38, 45/43 db), can be tested, optical fiber breakpoint position; full loss of the optical fiber link; distribution of loss along the length of the optical fiber; connection loss of the optical fiber connection point.

In order to test the accuracy, the pulse size and width of the OTDR tester should be appropriately selected and set according to the index of refractive index n given by the manufacturer. When determining the fault point, if the optical cable length is unknown in advance, you can first put it in the automatic OTDR, find the general location of the fault point, and then put it in the advanced OTDR. Select a smaller pulse size and width, but it must correspond to the optical fiber length. The blind area is reduced until it is coincident with the coordinate line. The smaller the pulse width, the more precise the pulse is. Of course, when the pulse is too small, the curve shows the noise, to be right. Then, we add a fiber tray to prevent blind spots in the near area from being detected. When determining a breakpoint, if the breakpoint is not in the next box, the next box will be opened and the OTDR tester will be connected to test the accurate distance between the fault point and the test point. The fault point can be easily located using the meter mark on the optical cable. When the meter mark is used to find the fault, there is another twist Rate Problem in the pair layer optical cable, that is, the length of the optical cable is not equal to the length of the optical fiber, the length of the optical fiber is about 1.005 times the length of the optical fiber. The above method can be used to successfully exclude multiple breakpoints and high loss points.