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Guide To Fiber Optic Splice Closure

Fiber optic splice closure is usually used with outdoor fiber optic cables, provides space for the outdoor fiber optic cables to be spliced together. The fiber optic splice closures and the fiber trays inside will protect the spliced fiber and the joint parts of the outdoor fiber cables. Generally the fiber optic splice closures are dome type and horizontal types, and Horizontal Fiber optic Splice Closure is used more often.

Structure Of Fiber Splice Closures
The fiber splice closures are made from special industrial grade, high tension plastic with a reliable moisture barrier. They are also optimized to resist aging of the material due to factors in the natural environment such as ultraviolet light.

There are two main types of closures, fiber optic and fiber optic terminal. A closure is hardware used to restore integrity of fiber cables entering the enclosure. The terminal is a hardened external connector that allows the addition of one or more fiber cables to the enclosure. These two categories can be configured as butt closures and in-line closures. The butt closure allows cables to enter from one end, while the in-line allows entry from both ends. Both the butt closures and in-line closures can be one of the following types:

Fiber Optic Splice Closures Key Features:

The box add aging-resistant in imported high tensile construction plastic out-faster is made up of stainless steel;
Overlap structure in splicing tray easy to install;
Suitable for ordinary fiber and ribbon fiber;
Perfect leak proofness and fine function;
Perfect and reliable sealing operations;
Fiber-bending radium guaranteed more than 40mm;
Full accessories for convenient operations;
Fiber optic splice closure can be used repeatedly;
High reliability;
For aerial, and direct buried applications.

Fiber Optic Splice Closure Types

For outside plant splice closure, there are two major types: horizontal type and vertical type.

1) Horizontal type

Horizontal type splice closures look like flat or cylindrical case. They provide space and protection for optical cable splicing and joint. They can be mounted aerial, buried, or for underground applications. Horizontal types are used more often than vertical type (dome type) closures.

Most horizontal fiber closure can accommodate hundreds of fiber connections. They are designed to be waterproof and dust proof. They can be used in temperature ranging from -40°C to 85°C and can accommodate up to 106 kpa pressure. The cases are usually made of high tensile construction plastic, are widely used in CATV, telecommunications and fiber optic networks.

2) Vertical Type

Vertical type of fiber optic splice closures looks like a dome, thus they are also called dome fiber optic splice closure. They meet the same specification as the horizontal types. They are designed for buried applications.

Vertical fiber optic splice closures are made of excellent engineering plastics, they are with 1inlet/outlet ports, 2inlet/outlet ports, 3inlet/outlet ports types, fitting different fiber optic core numbers. The vertical fiber optic splice closure is used in CATV, telecommunications and fiber optic networks.

Fiber splice closures accept both Ribbon Cable and round fiber cables. Each type (ribbon or round cable) fits respective requirement of different fiber splicing counts. They are widely used in optic telecommunication systems. JFOPT offers fiber optic splice closure, vertical, horizontal, dome, from 2 cores to 240 cores maximum, with inside fiber optic splice trays accessories like fusion splice sleeves.

Related fiber products visit at jfcable.com and jfopt.es

A Quick Guide To Fiber Optic Power Meter

When you install and terminate fiber optic cables, you always have to test them. A test should be conducted for each fiber optic cable plant for three main areas: continuity, loss, and power. And optical power meters are part of the toolbox essentials to do this. There are general-purpose power meters, semi-automated ones, as well as fiber optic power meters optimized for certain types of networks, such as FTTx or LAN/WAN architectures. It’s all a matter of choosing the right gear for the need.

Handheld Optical Laser Source JFT-03

Handheld Optical Laser Source JFT-03

Here is a quick guide to fiber optic power meters and how they work.

Optical power meters are commonly used to measure absolute light power in dBm. For dBm measurement of light transmission power, proper calibration is essential. A fiber optic power meter is also used with an optical light source for measuring loss or relative power level in dB. To calculate the power loss, optic power meter is first connected directly to an optical transmission device through a fiber optic pigtail, and the signal power is measured. Then the measurements are taken at the remote end of the fiber cable.

Fiber optic power meter detects the average power of a continuous beam of light in an optical fiber network, tests the signal power of laser or light emitting diode (LED) sources. Light dispersion can occur at many points in a network due to faults or misalignments; the power meter analyzes the high-powered beams of long-distance single-mode fibers and the low-power multibeams of short-distance multimode fibers.

Important specifications for fiber optic power meters include wavelength range, optical power range, power resolution, and power accuracy. Some devices are rack-mounted or hand held. Others are designed for use atop a bench or desktop. Power meters that interface to computers are also available.

The fiber optic power meter is a special light meter that measures how much light is coming out of the end of the fiber optic cable. The power meter needs to be able to measure the light at the proper wavelength and over the appropriate power range. Most power meters used in datacom networks are designed to work at 850nm and 1300nn. Power levels are modest, in the range of –15 to –35dBm for multimode links, 0 to –40dBm for single mode links. Power meters generally can be adapted to a variety of connector styles such as SC, ST, FC, SMA, LC, MU, etc.

Generally, multimode fiber is tested with LEDs at both 850nm and 1300nm and single mode fiber is tested with lasers at 1310nm and 1550nm. The test source will typically be a LED for multimode fiber unless the fiber is being used for Gigabit Ethernet or other high-speed networks that use laser sources. LEDs can be used to test single mode fibers less than 5000 meters long, while a laser should be used for long single mode fibers.

Most fiber optic power meters are calibrated in linear units such as milliwatts or microwatts. They may also provide measurements in decibels referenced to one milliwatt or microwatt of optical power. Typically, fiber optic power meters include a removable adaptor for connections to other devices. By measuring average time instead of peak power, power meters remain sensitive to the duty cycle of digital pulse input streams.

Use fiber optic power meter and other useful fiber optic test equipment to ensure that your fiber optic system will operate smoothly.

What is Single-mode optic fiber

Fiber with a core diameter less than about ten times the wavelength of the propagating light cannot be modeled using geometric optics. Instead, it must be analyzed as an electromagnetic structure, by solution of Maxwell’s equations as reduced to the electromagnetic wave equation. The electromagnetic analysis may also be required to understand behaviors such as speckle that occur when coherent light propagates in multi-mode fiber. As an optical waveguide, the fiber supports one or more confined transverse modes by which light can propagate along the fiber. Fiber supporting only one mode is called single-mode or mono-mode fiber. The behavior of larger-core multi-mode fiber can also be modeled using the wave equation, which shows that such fiber supports more than one mode of propagation (hence the name). The results of such modeling of multi-mode fiber approximately agree with the predictions of geometric optics, if the fiber core is large enough to support more than a few modes.

The waveguide analysis shows that the light energy in the fiber is not completely confined in the core. Instead, especially in single-mode fibers, a significant fraction of the energy in the bound mode travels in the cladding as an evanescent wave.

The most common type of single-mode fiber has a core diameter of 8–10 micrometers and is designed for use in the near infrared. The mode structure depends on the wavelength of the light used, so that this fiber actually supports a small number of additional modes at visible wavelengths. Multi-mode fiber, by comparison, is manufactured with core diameters as small as 50 micrometers and as large as hundreds of micrometers. The normalized frequency V for this fiber should be less than the first zero of the Bessel function J0 (approximately 2.405).

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