Fiber Glossary

Insertion loss and return loss are two important data factors when evaluating the quality of many passive fiber optic components, such as fiber optic patch cords and fiber optic connectors, etc..

Insertion loss refers to the fiber optic light loss caused when a fiber optic component is inserted into another to form the fiber optic link. Insertion loss can result from absorption, misalignment or an air gap between the fiber optic components. We want the insertion loss to be as small as possible. Our fiber optic components insertion loss is less than 0.2dB typically, while components with insertion loss less than 0.1dB are available on request.

Return loss is when the fiber optic light gets reflected back at or to the connection point. The higher the return loss, the lower the reflection, which results in better connection. According to industry standard, Ultra PC polished fiber optic connectors return loss should be more than 50dB. Angled polished fiber optic connectors generally have a return loss of more than 60dB. PC fiber optic connectors should have a return loss of more than 40dB.

During the manufacturing procedure, state of the art equipment is used to test both the insertion loss and return loss, our products are individually tested prior to shipment by our QC Department, which leads to full compliance exceeding the industry standard.

Plenum Fiber Cable

Plenum Rated Fiber Optic Cable (NEC 770 OFNP):

The word Plenum is also commonly referred to as (CMP) called Communications Plenum Cable. Let’s first make clear how and why the word Plenum is important, and then discuss what the Plenum Rated Fiber Optic Cable is and when and where it is used. See the illustration below.

According to National Electric Code (NEC), a plenum is a "compartment or chamber to which one or more air ducts are connected and forms part of the air distribution system." that is to say, as a plenum, the space above an acoustic tile ceiling would have to extend above other rooms in the same building or be open to ducts connecting it to other parts of the building. The concern is that during a fire, if there is burning material in a plenum air space, smoke and fumes can travel through air ducts to the whole building. For this reason, there are codes to restrict the types of materials (such as cables) that can be placed in the plenum.

Plenum-rated fiber optic cables are different from other types of cabling by the special types of plastics used in the fiber optic cable jackets. Because plenum cables are routed through air circulation spaces, which contain very few fire barriers, they need to be coated in flame-retardant, low smoke materials. These plastics offer good resistance against possible fire, and in the event that they do begin to burn, they will not emit large quantities of harmful fumes.

Although the National Electric Code may allow non-plenum cable, the final decision is up to your local Fire Marshall. Most cities adopt the national codes as their own without revision, but some cities modify or expand them and require plenum-rated cable in all situations. Regardless of the code or its interpretation, your Fire Marshall makes the final decision. We recommend that you contact your Fire Marshall if you have questions.

We supply Plenum-Rated Fiber Bulk Cable and Plenum-Rated Fiber Patch Cords, such types include SC, FC, LC, ST, MU, MTRJ, E2000, MTP, MPO, DIN, D4, ESCON, FDDI, SMA, etc., both Single-Mode and Multi-Mode Plenum-Rated Fiber Cable assemblies available.

Riser Fiber Cable

Optical fiber, nonconductive, riser (OFNR) is a type of optical fiber cable. As designated by the National Fire Protection Association (NFPA), this name is used for interior fiber-optic cables which contain no electrically conductive components, and which are certified for use in riser applications; they are engineered to prevent the spread of fire from floor to floor in a building. Typically they are tested for compliance with ANSI/UL 1666-1997, Standard Test for Flame Propagation Height of Electrical and Optical-Fiber Cable Installed Vertically in Shafts. NFPA NEC 2005 Art 770.51(B) FPN.

They are distinct from optical fiber, nonconductive, plenum cable (OFNP), and general-purpose optical cable.

OFNR cables can not be installed in plenum areas since they do not have the required fire and smoking rating as Plenum rated cables. OFNP plenum cables can be used as substitutes for OFNR cables.

RoHS Fiber Optic Cable

RoHS Compliant Fiber Optic Products

RoHS is the short form for the Restriction of Hazardous Substances in electrical and electronic equipment and was a forced institution made by the European Union. RoHS is made for environmental protection and to protect the health of the products' users. RoHS mentioned six types of hazardous substances: Pb,Cd, Hg, Cr6+, PBDE and PBB. RoHS restriction was put into effect July 1st, 2006. Since that time, all products imported to Europe need to be compliant to RoHS standards.

The hi-tech industry from all over the world has experienced a significant shift in the approach to potentially hazardous materials commonly used in the electronics and hi-tech manufacturing. With the implementation of RoHS and WEEE, many technology companies have adopted programs to ensure compliance with the necessary directives for environmental sustainability.

Fiber optic products exported to Europe also need to be compliant to RoHS standards. RoHS has more to do with the raw materials in this industry because fiber optic assemblies are only the work of assembly and no new substances are generated during this process. All of the fiber optic cables, especially the cable jacket, and the fiber optic connector housings and components used, should be environmentally protective and not do harm to user's health.

Simplex & Duplex Fiber Cable

Simplex Fiber Optic Patch Cords are made using simplex fiber optic cables. Simplex means this type of cable is structured with only one thread of fiber optic glass inside the single core and has one single outer jacket.

Duplex Fiber Optic Patch Cords can be regarded as two simplex cables having their jackets co-joined by a strip of jacket material. Some duplex fiber optic patch cords have clips on the two fiber optic connectors at each side of the cable to combine the two connectors together. Below are pictures to illustrate what is simplex and what is duplex:

As in this picture, the left is a simplex LC APC type fiber optic patch cable, with simplex fiber optic cable. The right is a duplex LC APC type fiber optic patch cable, with duplex fiber optic cable and has clips to combine the two connectors.

There are also multi-fiber cables. Both simplex and multi-fiber cables have a single outer jacket, but simplex only has one thread fiber glass inside the core, while multi-fiber has many threads of fiber optic glass inside the core. Multi-fiber cables can be a ribbon type or a bundle type.

Simplex and duplex type fiber optic cables are different from single-mode and multi-mode which are related to fiber optic glass types.

Single-Mode Fiber & Multi-Mode Fiber

First of all, we have to know there is no difference in fiber optic light, there is no "single mode fiber optic light" or "multi-mode fiber optic light", there is only one type. Here "mode" means the way of movement of the fiber optic light inside the media - fiber optic glass core. Light in the single-mode fiber glass, also known as media, travels almost straight ahead, while in the multi-mode fiber glass, the light bounces between the inner walls of the fiber like mirrors.

What is single-mode fiber optic cable and what is multi-mode fiber optic cable?

It is easy to judge this from the outer appearance for indoor cables and fiber optic patch cords. Single-mode fiber optic cables and single-mode fiber optic patch cords typically have a yellow outer jacket, and on the cable there are usually words printed such as " 9/125 SMF." SMF means Single-Mode Fiber, 9/125 is the fiber glass diameter and fiber core diameter (fiber glass with cladding). Multi-mode fiber optic cable and multi-mode fiber optic patch cords are usually orange and have words like "MMF 50/125" or "MMF 62.5/125" printed on the cable outer jacket.

Single-mode cables are used for long distance transmission, while multi-mode is used for shorter distances. Single-mode fiber optic cables are typcially less expensive when compared with multi-mode fiber optic cables. The reason for this is that the multi-mode fiber optic cable manufacturing procedure is a bit more complicated, which generally means more time.

This is a LC to FC single mode fiber optic cable with single-mode fiber and yellow color jacket.

Single-mode fiber optic cables

This is an MTRJ multi-mode fiber optic cable with multi-mode fiber and an orange color jacket.
Multi-mode fiber optic cables

We supply a wide range of products made of both single-mode fiber and multi-mode fiber. We not only supply the common types fiber, but we also supply special types such as bendable single-mode fiber and laser optimized multi-mode fiber.

WDM

WDM is the short form of Wavelength Division Multiplexing. In our products range, there are WDM products in the fiber optic coupler series and the WDM fiber optic media converters, and here we explain what the WDM is.

In the early times, fiber optic signal transmission was limited to one wavelength per glass fiber. Because fiber optic cables allow large bandwidth, people found a way to enable various kinds of fiber optic light to transmit through a single fiber glass in different wavelengths, called WDM (Wavelength Division Multiplexing) technology. With WDM, costs can be lowered. Instead of using many fiber optic cables, one cable can perform more functions.

Earlier WDM technology only transmitted 1310nm and 1550nm wavelength fiber optic light. Below is a picture to illustrate how it works.

WDM

The WDM structure looks similar to a common fiber optic coupler, but they are different in many ways. Fiber optic couplers divide the same wavelength fiber optic signals by different ratios such as 1:99, while WDM divide the two different wavelengths of fiber optic light as shown in the above illustration.

We provide WDM fiber optic media converters, also called single fiber bi-direction fiber optic media converters. These units also adopt the WDM technology and are generally used in pairs, where one converter has a 1310nm transmitter and a 1550nm receiver. Another similar device uses a 1550nm transmitter and a 1310nm receiver. The two converters form a pair to work in conjunction with one another. WDM fiber optic media converters must be used in pairs.

LSZH Fiber Cable

LSZH, also called LSOH, stands for Low Smoke Zero Halogen. At Fiber Savvy, we supply a wide range of LSZH Fiber Optic Cables and LSZH Fiber Optic Patch Cords.

The inner structure of LSZH fiber optic patch cord is similar to common fiber optic cables. The function and technique parameter is also similar. The main difference is the jacket each one is wrapped in. LSZH fiber optic jackets are more fire-resistant compared with common PVC jacketed cables, even when they are on fire. When burned, LSZH cables emit low smoke and no halogen substances. This feature is designed to not only protect the environment, but the low smoke is also important to the safety and presence of people and the facilities that could be on fire.

LSZH fiber optic cables and LSZH fiber optic patch cords are required for the RoHs compliant cable assemblies. LSZH fiber optic patch cables are widely used in high buildings, airports, libraries, and other public places where expensive equipment could be damaged or many people would be harmed from exposure to corrosive gases.

PC/UPC/APC Polish Types

PC, UPC and APC Fiber Optic Patch Cable Assemblies

Physical Contact (PC), Ultra Physical Contact (UPC) and Angled Physical Contact (APC) refer to the polish style of a fiber optic ferrule. Unlike copper cables which use copper thread inside of the connectors to establish a data connection, fiber optic connectors use ceramic or phosphorus bronze ferrules to make the data connection. Different fiber optic connectors have varying ferrule size, length and polish styles. PC and UPC polish styles are used in both multimode and single mode applications, while APC can only be used for single mode.

The polish of the ferrules result in different levels of performance, mainly on the back reflection (return loss); the higher the return loss, the greater the performance of the cable. Each polish type has a minimum return loss, as seen below:

Insertion loss for all polishes is less than 0.3dB; the lower the insertion loss, the greater the performance of the cable.

Coil Fiber Patch Cord

Coil fiber optic cable assemblies have a curled structure. Coil fiber optic patch cords have variable lengths just like the common telephone cable. This feature makes it suitable for use in connecting fiber to the home and fiber to the desktop and to connect the server or equipment or racks. Coil fiber optic cable provides flexibility in places where users require frequent movement and changes of fiber optic connections and where users need a length variable connection. Examples of this are from a wall plate to a personal computer, from mobile test equipment to the tested devices, or temporarily connection of equipment in different rooms.

Currently we use POF to make the coil fiber optic patch cords. We are able to develop a series of fiber optic special connectors to fit for this cable and make the assemblies like ST, SC, FC, LC, MT-RJ, etc. The diameter of the coil structure is variable and many of the cable parameters can be custom designed, such as the cable outer diameter, cable length, cable jackets, and fiber connector polishes. With a special coil structure, this kind of fiber optic patch cord can function just as well as traditional fiber optic patch cables. The curled fiber optic patch cord is available in simplex and duplex only.

NEMA Ratings

In Non-Hazardous Locations, the specific enclosure Types, their applications, and the environmental conditions they are designed to protect against, when completely and properly installed, are as follows:

NEMA 1 Enclosures - constructed for indoor use to provide a degree of protection to personnel against access to hazardous parts and to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt).

NEMA 2 Enclosures - constructed for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); and to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing).

NEMA 3 Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); and that will be undamaged by the external formation of ice on the enclosure.

NEMA 3R Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); and that will be undamaged by the external formation of ice on the enclosure.

NEMA 3S Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); and for which the external mechanism(s) remain operable when ice laden.

NEMA 3X Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); that provides an additional level of protection against corrosion and that will be undamaged by the external formation of ice on the enclosure.

NEMA 3RX Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); that will be undamaged by the external formation of ice on the enclosure that provides an additional level of protection against corrosion; and that will be undamaged by the external formation of ice on the enclosure.

NEMA 3SX Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow); that provides an additional level of protection against corrosion; and for which the external mechanism(s) remain operable when ice laden.

NEMA 4 Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow, splashing water, and hose directed water); and that will be undamaged by the external formation of ice on the enclosure.

NEMA 4X Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (windblown dust); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (rain, sleet, snow, splashing water, and hose directed water); that provides an additional level of protection against corrosion; and that will be undamaged by the external formation of ice on the enclosure.

NEMA 5 Enclosures - constructed for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and settling airborne dust, lint, fibers, and flyings); and to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing).

NEMA 6 Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (hose directed water and the entry of water during occasional temporary submersion at a limited depth); and that will be undamaged by the external formation of ice on the enclosure.

NEMA 6P Enclosures - constructed for either indoor or outdoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (hose directed water and the entry of water during prolonged submersion at a limited depth); that provides an additional level of protection against corrosion and that will be undamaged by the external formation of ice on the enclosure.

NEMA 12 Enclosures - constructed (without knockouts) for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and circulating dust, lint, fibers, and flyings); and to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing).

NEMA 12K Enclosures - constructed (with knockouts) for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and circulating dust, lint, fibers, and flyings); and to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing).

NEMA 13 Enclosures - constructed for indoor use to provide a degree of protection to personnel against access to hazardous parts; to provide a degree of protection of the equipment inside the enclosure against ingress of solid foreign objects (falling dirt and circulating dust, lint, fibers, and flyings); to provide a degree of protection with respect to harmful effects on the equipment due to the ingress of water (dripping and light splashing); and to provide a degree of protection against the spraying, splashing, and seepage of oil and non-corrosive coolants.