What are the ways to distinguish the quality of optical cables?

1. Outer sheath:

1. The outer sheath of the indoor optical cable is generally made of polyvinyl chloride (PVC) or flame retardant polyethylene or polyurethane (LSZH) material. The outer skin is smooth, bright, flexible and easy to peel. Inferior optical cables have poor surface finish, and are easy to stick with tight sleeves and aramid fibers.

2. The outer sheath of the outdoor optical cable should be made of high-quality black polyethylene (HDPE, MDPE). After the cable is formed, the outer sheath should be flat, bright, uniform in thickness and free of bubbles. The outer sheath of the inferior optical cable is mostly produced with recycled materials. The skin of the inferior optical cable is rough, because there are many impurities (lime powder) in the raw material, which shows that there are many tiny pits in the outer sheath of the optical cable. Whitening, the outer skin will crack and seep after the optical cable is laid for a period of time.

2. Optical fiber:

Regular optical cable manufacturers will use the A-level cores of major manufacturers. Low-cost and low-quality optical cables usually use C-class, D-class optical fibers and smuggled optical fibers of unknown origin. These optical fibers are often damp and discolored due to complex sources and long delivery times, and multi-mode optical fibers are often mixed with single-mode optical fibers. However, the general small factory lacks the necessary testing equipment and cannot judge the quality of the optical fiber. These fibers cannot be distinguished by the naked eye. The common problems encountered in construction are: narrow bandwidth and short transmission distance; uneven thickness, which cannot be connected with pigtails; lack of flexibility of optical fibers, and it is very easy to break the column when the fiber is coiled.

3. Strengthen the steel wire:

The steel wire of the outdoor optical cable of the regular manufacturer is phosphating, and the surface is gray. This kind of steel wire does not increase the hydrogen loss after cabling, does not rust, and has high strength. Inferior optical cables are mostly replaced with thin iron or aluminum wires. The identification method is that the appearance is white, and it can be bent at will when pinched in the hand. The optical cable produced with such steel wire will generate additional hydrogen loss in the future, and at the same time, the two ends of the connecting optical fiber box will rust and break for a long time.

How to distinguish between good and bad optical cables?

Fourth, armored steel belt:

Formal production enterprises use double-sided brushed rust-proof and plastic-coated longitudinally-wrapped steel strips. Inferior optical cables are made of ordinary iron sheets, and usually only one side has been treated with rust prevention.

5. Optical fiber sleeve:

The loose tube wrapping the optical fiber in the optical cable should be made of PBT material. The tube of this material has high strength, no deformation, and anti-aging. Inferior optical cable sleeves are usually produced with PVC materials. The outer diameter of such sleeves is very thin and soft, and can be flattened when squeezed by hand. It is no different from drinking straws and cannot protect optical fibers well.

Six, fiber paste:

The fiber paste in the outdoor optical cable can prevent the optical fiber from silver streak, hydrogen loss, and even breakage caused by moisture. There is very little fiber paste used in inferior optical cables, and some air bubbles can be observed with the naked eye. Or use inferior fiber paste, which seriously shortens the service life of the fiber optic cable.

7. Aramid:

Also known as Kevlar, it is a high-strength chemical fiber, which is currently most used in the military industry. Military helmets and bulletproof vests are produced with this material. At present, the aramid fiber above the market is mainly the American DuPont brand. Both indoor optical cables and power overhead optical cables (ADSS) use aramid yarns as reinforcements. Due to the high cost of aramid fiber (2,000 million yuan/ton), inferior indoor optical cables are generally made very thin in outer diameter, which can save costs by reducing a few strands of aramid. This kind of optical cable is easy to be broken when passing through the tube. .

Eight, cable paste:

The fiber paste in the outdoor fiber optic cable is attached to the outside of the fiber optic sleeve to protect the fiber optic cable from moisture. The high-quality cable paste is evenly mixed, and there will be no separation after long-term use. In the inferior fiber optic cable, the cable paste will volatilize, or the filling will not affect the moisture barrier performance of the fiber optic cable.