A Guide for Choosing the Fiber Optic Cable for Your Application

Fiber optic cables form the core of various cable infrastructures. These cables have gained immense popularity over copper cables owing to several benefits that they offer such as the ability to transmit signals to long distances. Owing to their popularity, these cables are now available in various types, thereby making the selection difficult. This paper aims to simplify this selection by offering a short and handy fiber optic selection guide.

Gain a Brief Understanding of Fiber Optic Cable and Its Benefits

Before getting into details of selecting the right fiber optic cable, let’s gain a brief understanding of this cable type and its typical advantages over copper cables.

A fiber optic cable is named so based on the optical fibers that it has. The fibers are mainly strands of glass or plastic that can carry optical signals through it. The fibers are contained in a thin jacket known as cladding. The fibers are contained within a thick overall jacket to make a cable. The electrical signals are produced by transmitting device is converted into optical signals inside the cable using optical transmitters. The optical pulses are again converted at the delivery end into electrical signals and transmitted. A fiber link needs two types of fibers – one for sending as well as one for receiving.

Now, coming to the key question – why fiber optic cables are gaining popularity than copper cables. The following pointers will help you understand it better.

• Fiber optic cables have high data transmission capacity over copper cables.
• They experience minimal signal loss compared to copper cables.
• Fiber optic cables are not prone to electromagnetic interference, which makes them popular over copper cables in various applications. This is because unlike copper cables these cables do not transmit electrical signals.
• Copper cables pose great security problems due to leakage and tampering. Against this, fiber optic cables do not radiate and are not easy to tamper with.
• Copper cables are expensive whereas fiber optic cables are much affordable and incur low costs in the long run.
• The transmission speed of fiber optic cables is increasing and today it can achieve 40 Gbps or more.

Types of Cables Based on Fibers

The following are the two types of fiber optic cables based on fibers:

• Single mode Fibers: The cables possess a small core size of less than 10 micrometers. This allows only one mode of light to pass through. The core allows light in the wavelength of 1310 nm to 1550 nm to pass through it. As the cable allows only one mode to pass through it, so there is very little reflection. This further lowers the attenuation rate and allows the signal to travel long distances. This is one of the reasons why these cables are used for applications demanding long-distance transmissions and extreme bandwidths.

• Multimode Fibers: The cables of this type have large cores of 50 micrometers – 62.5 micrometers. These large diameter cores enable multiple modes to pass through them. Thus, the cable can enable more data to pass through them than single mode fiber. The multiple modes can create high attenuation and dispersion rates, which reduce signal quality over long distances. Multimode fiber optic cables can transmit infrared light produced by LEDs. These cables are usually preferred for mid to short range distance applications in a building or a campus. The following are a few popular multimode fibers used today.
  • 50/125 um Multimode Cables: These cables are a preferred choice in advanced equipment. In these 50 microns is a large bandwidth capacity.
  • 62.5/125 um Multimode Cables: It is an industry-standard cable that is used by most applications in the market.   
  • 50/125 um Laser Enhanced Multimode Cables: As the name suggests, this cable is designed for laser applications. It is mainly used for 10 Gigabit Ethernet applications up to 300-meter range.

Types of Fiber Optic Cables for Application

The cables are distinguished as indoor and outdoor cables based on the application or utilization. Although the name is obvious, some applications demand the use of indoor and outdoor cables at the same time. How to choose the fiber optic cable for indoor and outdoor applications? The following pointers aim to simplify your fiber optic cable selection.

• Indoor Cables: These cables are designed for indoor use and are usually convenient and easy to use. Indoor cables are most commonly used in homes, offices, and retail stores. These cables are not designed for harsh environments but are fire-resistant. Indoor fiber optic cables feature a tight buffered, one-fiber construction. The fiber is contained in a 3mm jacket. When two such fibers are joined using a thin web, it is called a zip cord. This zip cord is used for backplane, patch cord, as well as desktop applications. The indoor cables used for power distribution comprise several fibers that are tightly bundled in a jacket. The bundled fibers are lined with Kevlar strength members and fiberglass rob reinforcement to increase their strength. The addition of these strength members also helps prevent kinking.
• Outdoor Cables: As the name suggests, these cables are designed for outdoor uses. The cables are designed for more protection from moisture and other environmental elements. Ribbon fiber optic cables, loose tube fiber optic cables, aerial fiber optic cables, and armored fiber optic cables are a few popular types of cables in this category based on their construction. Underground fiber cables, direct buried fiber cables, aerial fiber cables, and underwater fiber cables are a few popular cables types in this category based on their application.

Types of Fiber Optic Cables Based on Communication Channels

Communication channels or data transmission channels are also one of the important considerations while selecting the right fiber optic cable. Based on the communication channels, the fiber optic cables are distinguished into the following types:

• Simplex Fiber Optic Cables: These fiber optic cables feature a single strand of plastic fiber, as well as an outer jacket. They enable one way data transfer, which is why they are called simplex. These fiber optic cables are most commonly used in applications such as automated speed and boundary sensors, digital data readouts, interstate highway sensor relays, and so on. The cables have a core of diameter 8 microns or 10 microns. As they carry data in only one way, so they are used to set up networks that are required to deliver data in one direction to long distances.
• Duplex Fiber Optic Cables: The cables have two fibers, which are included in a zip-cord arrangement. One fiber will transmit data in one direction and the other will transfer data in another direction at a time. The duplex fiber optic cables are distinguished into two types – full duplex and half duplex fiber optic cables based on transmission. In half-duplex fiber optic cables, the signals are transmitted in both directions. However, it is only transmitted in one direction at a time. In full-duplex fiber optic cable, the data is transmitted in two directions at the same time.

Popular Connectors for Fiber Optic Cables

This guide for choosing the fiber optic cable would be incomplete without the mention of connectors. The connector along with a fiber optic cable plays a key role in establishing a secure network connection. The following are a few popular types of connectors used in fiber optic cables.

• ST: This connector is usually twisted in place using a cylindrical twisted lock coupling. The connector stands out due to its round shape and has been popular for quite a long time because it was the first connector developed for commercial wiring applications. ST connector is also known as a bayonet-style connector because it is usually twisted to lock.
• SC: This is an abbreviation of Subscriber Connector. It is also known as a standard connector or square connector. SC connector is gaining popularity owing to its durability, low cost, and simple installation. They are used in passive and point-to-point optical networking applications. The connectors are kept in place using a push/pull mating mechanism.
• LC: These connectors are much similar to SC connectors but are smaller in comparison. They also follow a push/pull mating mechanism.  
• FC: The connectors of this type possess a threaded body and are widely used in high-vibration environments. These connectors are mainly used in polarized optical fibers and single mode optical fibers.
• MTRJ: The connectors look similar to RJ style modular plugs, which is where they get their name from.

In addition to these, there are MT/MTP type connectors that can accommodate up to 12 fiber strands and possess compact size.  The choice of the right type of connector will depend on your application requirements.

Fiber Optic Cable Jackets to Choose From

As discussed before fiber optic cable jackets add strength to fiber members enclosed within. There are different types of fiber optic cable jackets based on their material of construction. The following are a few popular ones.

• PVC: The jacket made of poly vinyl chloride or PVC is used in various applications such as low-voltage devices, computers, communication devices, and so on. They are not suited for high temperatures, heavy smoke, or hydrogen chloride gas applications. PVC jackets are commonly used for indoor and outdoor cables.
• PE: The cables with polyethylene jackets can withstand challenging weather and moisture. They possess good electrical properties and are largely abrasion-resistant. PE has emerged as an affordable and popular jacket material for outdoor fiber optic cables.
• LSZH: This stands for Low Smoke Zero Halogen, which means LSZH cables do not comprise halogenated materials. This reduces the chances of toxicity in the case of combustion.
• PVDF: These jackets are made of polyvinyl difluoride and are mainly used for plenum cables. These cables may produce little smoke when exposed to fire and possess better fire-retardant properties.

Fiber optic jackets are available in different colors, and they help you understand the type of cable you may be dealing with. You can also check the printed nomenclature for more details. For instance, single-mode cable for non-military and military applications are colored yellow and have nomenclature OS1, OS1a, OS2, SM/NZDS, and SM. Multimode cable 100/140 for non-military applications is colored orange and green for military applications and they may have the nomenclature OS1, OS1a, OS2, SM, and SM/NZDS.

Popular Accessories That You Would Need for Fiber Optic Cables

Focus on popular accessories is also important while selecting the fiber optic cables for your applications. The following are a few popular fiber optic accessories used in cable architecture.

• Media Converters: The converters are used to connect Cat 5/6 UTP cables to multimode or single mode fiber. In short, they are used to connect copper cables and fiber optic cables in applications. The media converters are distinguished as copper to fiber and fiber media converters based on their design and applications.
• Fiber Optic Network Switches: These devices enable users to boost their traffic and network speed. They are available in 4, 5, 6, 7, 8, 9, 10, 16, 24, 28, 52, and 24-port fiber optic models. PoE switches, industrial switches, and industrial PoE switches are a few variants of fiber optic network switches.
• SFP Transceivers: SFP is an abbreviation of small form-factor pluggable modules. They are used to connect fiber optic cables with networking equipment. SFP transceivers are used with multimode or single mode fiber optic cables and copper cables, too.

Conclusion:

This fiber optic cable selection guide covers all important types of fiber optic cables that you may want to consider for your network. The consideration would depend on several factors such as the amount of data to be transferred, environments, and distances to be covered, and so on. To exploit the advantages of fiber optic cables, you must use quality cables and fiber optic cable products from trusted manufacturers. Contact Us for more information on fiber optic cable products and kits.