This article is about Loose-tube Vs Tight-buffered Fiber Optic Cable, Difference Between Tight Buffered and Loose Tube Fibre and Tight-Buffered Cable vs. Loose-Tube Gel-Filled Cable.
Loose-Tube and Tight-Buffer Optical Fiber Cable
Optical fiber cable comes in different designs, each with its unique features and applications. Two of the most common designs are loose-tube and tight-buffer fibers. In this article, we will explore the differences between these designs and how they impact the termination and installation process.
Loose-tube Cable Design
Loose-tube cable designs are used in outside plant (OSP) applications, where the optical fiber is loosely placed within a protective tube. This design provides flexibility and can withstand environmental factors, such as temperature changes and moisture.
However, it requires a break-out kit (fan-out kit) to install a connector directly on the fiber. The kit includes a tube that slides over the fiber, protecting it and building the diameter up to fit standard connectors. Loose-tube splices should also be protected with a splice sleeve and stored in a splice tray.
Tight-buffer Fiber Design
Tight-buffer fibers have an additional layer of plastic that protects the fiber when additional cable layers have been removed. This design allows tight-buffer fibers to have a connector installed directly on the fiber, without the need for a break-out kit.
Connectors designed for this purpose have a strain-relief boot that fits the tight buffer. However, tight-buffer splices, including pigtail splices, should still be protected with a splice sleeve and stored in a splice tray.
Terminating Optical Fiber Cable To terminate optical fiber cable, the following steps should be followed:
- Verify that the correct termination components have been selected, compatible with both the fiber and the connecting hardware.
- Arrange the wiring scheme and organize the cable by destination.
- Trim the cable length to reach the termination point without putting the cable under stress or violating the bend radius.
- Follow the connectivity hardware manufacturer’s instructions for installing the termination hardware/connectors. Ensure that nothing crushes or excessively bends fibers and/or tubes.
- Properly bond and ground any cables with metallic components.
- If using a pigtail, protect all splices with a splice sleeve and suitable splice enclosure.
- Loosely bundle all exposed cables, preferably with hook-and-loop style straps.
- Clear out the work area.
Conclusion
The choice between loose-tube and tight-buffer fiber designs depends on the application and installation environment. Loose-tube designs are commonly used in outside plant applications, while tight-buffer designs are ideal for indoor installations. When terminating optical fiber cable, it is essential to follow the manufacturer’s instructions to avoid damaging the fibers and ensure proper installation. By understanding the differences between these designs and following best practices during termination and installation, you can achieve a reliable and robust optical fiber network.
FAQs
1. What is the difference between tight buffer and loose tube buffer fiber?
Tight buffer and loose tube fiber cables are two types of fiber optic cables used for different applications. While both have the same basic function of transmitting data over long distances, the way they are constructed differs significantly. In this article, we will explore the differences between tight buffer and loose tube fiber cables.
Tight buffer fiber cables are constructed with the fiber core directly surrounded by a protective coating layer, followed by a cladding layer. The core is the central part of the fiber that carries the light signal, while the coating and cladding layers protect it from damage. In tight buffer cables, there is no gap between these layers, resulting in a more compact design. This type of cable is often used for indoor applications, such as data centers or buildings where the cables are not exposed to harsh environmental conditions.
On the other hand, loose tube fiber cables have a gap between the fiber core and the protective layers. This gap can either be filled with a gel-like substance or left empty. The fibers are bundled together in tubes, which are then placed inside the outer protective layer. This design provides more flexibility and protection against moisture, making it ideal for outdoor applications such as in telecommunications, oil and gas, and other industrial settings.
One of the advantages of tight buffer fiber cables is that they are easier to terminate and splice. Because there is no gap between layers, connectors can be directly installed on the fiber, and splices are easier to protect with splice sleeves. This makes tight buffer cables a good choice for indoor applications where installation and maintenance are critical.
Loose tube fiber cables, on the other hand, require a breakout kit to install connectors directly on the fibers. The kit includes a tube that slides over the fiber, protecting it and building the diameter up to fit standard connectors. While this adds an extra step to the installation process, loose tube cables provide better protection against harsh outdoor environments.
2. What are the advantages of a loose buffer tube fiber?
Loose buffer tube fiber optic cables offer several advantages over their tight buffer counterparts. Some of the benefits of loose buffer tube fiber include:
- Improved protection against environmental factors: Loose buffer tubes provide an added layer of protection around the fibers. This layer helps to insulate the fibers from external forces such as moisture, dust, and temperature changes. Loose buffer tube fibers are well suited for outdoor installations because they can withstand harsh environmental conditions.
- Lower cable attenuation: In loose buffer tube fiber optic cables, the fibers are loosely placed within the tube. This design reduces the chances of microbending in any given fiber. Microbending can cause attenuation or signal loss. The reduced microbending leads to lower cable attenuation and better transmission characteristics.
- High level of isolation from external forces: Loose buffer tube fiber optic cables offer a high level of isolation from external forces. This isolation is critical in applications where cables may be exposed to high mechanical stress. The loose buffer tube permits more stable transmission characteristics, making it suitable for long-distance applications.
- Flexibility: The loose buffer tube design makes the fiber optic cables more flexible. This flexibility is essential in applications where cables need to bend or curve. The flexibility also makes installation easier, especially in tight spaces.
- Easy to terminate: Loose buffer tube fiber optic cables are relatively easy to terminate. They do not require a breakout kit as with tight buffer tubes. A connector can be installed directly on the fiber, making termination quicker and less complicated.
3. In which application would you not normally use loose tube fiber?
Loose-tube fibers are not normally used in applications where the cables need to be submerged or routed around multiple bends. The loose tubes inside the cable can fill with water when submerged, leading to signal loss and damage to the cable.
Additionally, loose-tube fibers have a larger minimum bend radius compared to tight-buffered fibers, which makes them unsuitable for applications that require multiple bends.
In these situations, tight-buffered fibers are preferred because of their smaller minimum bend radius and increased flexibility, which allows them to be easily routed through tight spaces and around multiple bends without affecting the signal quality.
4. Which is better OS1 or OS2?
The choice between OS1 and OS2 fiber optic cable depends on the specific needs of the application. However, generally, OS2 is considered better than OS1 because it offers longer transmission distances and higher bandwidth capacity.
OS2 is designed for longer distances and can support higher speeds, making it suitable for applications that require higher bandwidth, such as data centers, telecom networks, and long-distance transmission. OS1 is suitable for shorter distances, such as those found in small to medium-sized buildings.
5. What is the purpose of loose tube fiber optic cable?
Loose tube fiber optic cable is mainly used for long-distance and outdoor applications due to its ability to withstand harsh environmental conditions. The purpose of this type of cable is to protect the fiber core, cladding, and coating from damage caused by external forces such as moisture, temperature changes, and physical impacts.
The loose buffer tubes surrounding the fibers provide extra protection and flexibility, allowing the cable to bend and twist without damaging the delicate fibers inside. This makes loose tube fiber optic cable ideal for use in applications such as telecommunications, data centers, and military and aerospace communications.