Copper Cabling

Category

Type

Frequency Bandwidth

Applications

Notes

Cat1

 

0.4 MHz

Telephone & Modem Lines

Not described in EIA/TIA recommendations.

Unsuitable for modern systems.

Cat2

 

 

Older terminal systems

Not described in EIA/TIA recommendations.

Unsuitable for modern systems.

Cat3

UTP

16 MHz

10BASE-T and 100BASE-T4  Ethernet

Described in EIA/TIA-568. Unsuitable for speeds above 16 Mbit/s. Now mainly used for telephone cables.

Cat4

UTP

20 MHz

16 Mbit/s

Not commonly used.

Cat5

UTP

100 MHz

100BASE-TX & 1000BASE-T Ethernet

Common in most current LANs

Cat5e

UTP

100 MHz

100BASE-TX & 1000BASE-T Ethernet

Enhanced Cat5. Same construction as Cat5, but with better testing standards.

Cat6

UTP

250 MHz

1000BASE-T Ethernet

Most commonly installed cable in Finland according to the 2002 standard. SFS-EN 50173-1

Cat6e

 

250 MHz

 

Not described in EIA/TIA recommmendations.

Cat6a

 

500 MHz

10GBASE-T Ethernet

ISO/IEC 11801:2002 Amendment 2.

Cat7

S/FTP

600 MHz

Telephone, CCTV, 1000BASE-TX in the same cable.  10GBASE-T Ethernet.

Four pairs, S/FTP (shielded pairs, braid-screened cable). Development complete - ISO/IEC 11801 2nd Ed.

Cat7a

 

1000 MHz

Telephone, CATV, 1000BASE-TX in the same cable.  10GBASE-T Ethernet.

Four pairs, S/FTP (shielded pairs, braid-screened cable). Development complete - ISO/IEC 11801 2nd Ed. Am. 2.

Cat8

 

1200 MHz

Under development, no applications yet.

Four pairs, S/FTP (shielded pairs, braid-screened cable). Standard under development.

Unshielded Twisted Pair (UTP)

UTP cables are found in many Ethernet networks and telephone systems. A typical subset of these colors (white/blue, blue/white, white/orange, orange/white) shows up in most UTP cables.

 

For urban outdoor telephone cables containing hundreds or thousands of pairs, the cable is divided into smaller but identical bundles. Each bundle consists of twisted pairs that have different twist rates. The bundles are, in turn, twisted together to make up the cable. Pairs having the same twist rate within the cable can still experience some degree of crosstalk. Wire pairs are selected carefully to minimize crosstalk within a large cable.

 

UTP cable is also the most common cable used in computer networking. Modern Ethernet, the most common data networking standard, utilizes UTP cables. Twisted pair cabling is often used in data networks for short and medium length connections because of its relatively lower costs compared to optical fiber and coaxial cable.

UTP is also finding increasing use in video applications, primarily in security cameras. Many middle to high-end cameras include a UTP output with setscrew terminals. This is made possible by the fact that UTP cable bandwidth has improved to match the baseband of television signals. While the video recorder most likely still has unbalanced BNC connectors for standard coaxial cable, a balun is used to convert from 100-ohm balanced UTP to 75-ohm unbalanced. A balun can also be used at the camera end for ones without a UTP output. Only one pair is necessary for each video signal.

Cable Shielding

Comparison of some old and new abbreviations, according to ISO/IEC 11801:

Old name

New name

Cable Screening

Pair Shielding

UTP

U/UTP

none

none

STP

U/FTP

none

foil

FTP

F/UTP

foil

none

S-STP

S/FTP

braiding

foil

S-FTP

SF/UTP

foil, braiding

none

 

The code before the slash designates the shielding for the cable itself, while the code after the slash determines the shielding for the individual pairs:

TP = twisted pair

U = unshielded

F = foil shielding

S = braided shielding

Twisted pair cables are often shielded in an attempt to prevent electromagnetic interference. Because the shielding is made of metal, it may also serve as a ground.

However, usually a shielded or a screened twisted pair cable has a special grounding wire added called a drain wire. This shielding can be applied to individual pairs, or to the collection of pairs. When shielding is applied to the collection of pairs, this is referred to as screening. The shielding must be grounded for the shielding to work, and is improved by grounding the drain wire along with the shield.

Shielded twisted pair (STP or STP-A)

150 ohm STP shielded twisted pair cable defined by the IBM Cabling System specifications and used with token ring or FDDI networks. This type of shielding protects cable from external EMI from entering or exiting the cable and also protects neighboring pairs from crosstalk.

Screened twisted pair (ScTP or F/TP)

ScTP cabling offers an overall sheath shield across all of the pairs within the 100 ohm twisted pair cable. F/TP uses foil shielding instead of a braided screen. This type of shielding protects EMI from entering or exiting the cable.

Screened shielded twisted pair (S/STP or S/FTP)

S/STP (Screened Shielded Twisted Pair) or S/FTP (Screened Foiled Twisted Pair) cabling offer shielding between the pair sets and an overall sheath shield within the 100 Ohm twisted pair cable. This type of shielding protects EMI from entering or exiting the cable and also protects neighboring pairs from crosstalk.

S/STP cable is both individually shielded (like STP cabling) and also has an outer metal shielding covering the entire group of shielded copper pairs (like S/UTP). This type of cabling offers the best protection from interference from external sources, and also eliminates alien crosstalk.

Note that different vendors and authors use different terminology (i.e. STP has been used to denote both STP-A, S/STP, and S/UTP).

Fibre Optic Cables

Fiber-optic lines are strands of optically pure glass as thin as a human hair that carry digital information over long distances. They are also used in medical imaging and mechanical engineering inspection.

BRIEF OVER VIEW OF FIBER OPTIC CABLE ADVANTAGES OVER COPPER:

• SPEED: Fiber optic networks operate at high speeds - up into the gigabits
• BANDWIDTH: large carrying capacity
• DISTANCE: Signals can be transmitted further without needing to be "refreshed" or strengthened.
• RESISTANCE: Greater resistance to electromagnetic noise such as radios, motors or other nearby cables.
• MAINTENANCE: Fiber optic cables costs much less to maintain.

Fiber-optics use light pulses to transmit information down fiber lines instead of using electronic pulses to transmit information down copper lines.

Looking at the components in a fiber-optic chain will give a better understanding of how the system works in conjunction with wire based systems:

Transmitter - place of origin for information coming on to fiber-optic lines.

The transmitter accepts coded electronic pulse information coming from copper wire. It then processes and translates that information into equivalently coded light pulses.

A light-emitting diode (LED) or an injection-laser diode (ILD) can be used for generating the light pulses.

Using a lens, the light pulses are funneled into the fiber-optic medium where they travel down the cable. The light is most often 850nm for shorter distances and 1,300nm for longer distances.

Light pulses move easily down the fiber-optic line because of internal reflection. When this principle is applied to the construction of the fiber-optic strand, it is possible to transmit information down fiber lines in the form of light pulses. The core must a very clear and pure material for the light or in most cases near infrared light (850nm, 1300nm and 1500nm). The core can be Plastic (used for very short distances) but most are made from glass. Glass optical fibers are almost always made from pure silica, but some other materials, such as fluorozirconatefluoroaluminate, and chalcogenide glasses, are used for longer-wavelength infrared applications.

Laser light shining through a fiber optic cable is subject to loss of strength, primarily through dispersion and scattering of the light, within the cable itself. The faster the laser fluctuates, the greater the risk of dispersion. Repeaters may be necessary to refresh the signal in certain applications.

Single Mode Fibre Optic Cable

A single stand of glass fiber with a diameter of 8.3 to 10 microns that has one mode of transmission.  Single Mode Fiber with a relatively narrow diameter, through which only one mode will propagate typically 1310 or 1550nm. Carries higher bandwidth than multimode fiber, but requires a light source with a narrow spectral width.

Single Mode fiber is used in many applications where data is sent at multi-frequency (WDM Wave-Division-Multiplexing) so only one cable is needed - (single-mode on one single fiber)

Single-mode fiber gives you a higher transmission rate and up to 50 times more distance than multimode, but it also costs more. Single-mode fiber has a much smaller core than multimode. The small core and single light-wave virtually eliminate any distortion that could result from overlapping light pulses, providing the least signal attenuation and the highest transmission speeds of any fiber cable type.   

Multi Mode Fibre Optic Cable

Slightly bigger diameter, with common diameters in the 50-to-100 micron range for the light carry component. Most applications in which Multi-mode fiber is used, 2 fibers are used (WDM is not normally used on multi-mode fiber).

Multimode fiber gives you high bandwidth at high speeds (10 to 100MBS - Gigabit to 275m to 2km) over medium distances. Light waves are dispersed into numerous paths, or modes, as they travel through the cable's core typically 850 or 1300nm. Typical multimode fiber core diameters are 50, 62.5, and 100 micrometers. However, in long cable runs (greater than 3000 feet [914.4 meters), multiple paths of light can cause signal distortion at the receiving end, resulting in an unclear and incomplete data transmission so designers now call for single mode fiber in new applications using Gigabit and beyond.

Other

Telephone Cable

Twisted pair cabling is a type of wiring in which two conductors (the forward and return conductors of a single circuit) are twisted together for the purposes of cancelling out electromagnetic interference (EMI) from external sources.

In contrast to FTP (foiled twisted pair) and STP (shielded twisted pair) cabling, UTP (unshielded twisted pair) cable is not surrounded by any shielding. It is the primary wire type for telephone usage and is very common for computer networking, especially as patch cables or temporary network connections due to the high flexibility of the cables.


Most telephone wires are one or more twisted pairs of copper wire. The most common type is the 4-strand (2 twisted pair). This consists of red and green wires, which make a pair, and yellow and black wires, which make the other pair. One telephone line needs only 2 wires. Therefore it follows that a 4-strand wire can carry 2 separate phone lines. The twisting keeps the lines from interfering with each other.

There are 2 types of common modular plugs, the RJ-11 and the RJ-14. The most common is the RJ-11 which uses only 2 of the wires in a 4 (or more) strand wire. This is the same kind of plug that you use to plug your telephone into the wall. This is a 1-line plug. The RJ-14 uses 4 wires and is used to handle 2 lines, or 2-line phones.

Fire Alarm Cable

There are five basic types of Fire Alarm Cable:

  • FPL - Power Limited General Purpose
  • FPLR - Power Limited Suitable from Floor to Floor
  • FPLP - Power Limited Suitable for use in Ducts, Plenums, and other spaces
  • NPLF - Non-Power Limited General Purpose
  • NPLFP - Non-Power Limited Suitable for use in Ducts, Plenums, and other spaces

Fire alarm cables are placed into three broad categories: plenum, non-plenum, and riser. Each of these corresponds to another standardized category. Plenum cable, to be used in ducts or other enclosed air spaces, is called FPLP; non-plenum cable, to be used in applications such as surface wiring, is FPL; and riser cable, which can be used in applications that go vertically from floor to floor, is FPLR. All of these names reflect where the fire alarm cable can be installed safely.

Electrical Cable

Electrical cable is an assembly of two or more electrical conductors, usually held together with an overall sheath. The assembly is used for transmission of electrical power.

Electrical cables may be installed as permanent wiring within buildings, buried in the ground, run overhead, or exposed.

Electrical cables come in a variety of sizes, materials, and types, each particularly adapted to its uses. Large single insulated conductors are also sometimes called power cables in the industry.

Cables consist of three major components: conductors, insulation and protective jacket. The makeup of individual cables varies according to application. The construction and material are determined by three main factors:

  • Working voltage, determining the thickness of the insulation;
  • Current-carrying capacity, determining the cross-sectional size of the conductor(s);
  • Environmental conditions such as temperature, water, chemical or sunlight exposure, and mechanical impact, determining the form and composition of the outer cable jacket.

Cables for direct burial or for exposed installations may also include metal armor in the form of wires spiralled around the cable, or a corrugated tape wrapped around it. The armor may be made of steel or aluminum, and although connected to earth ground is not intended to carry current during normal operation.

Power cables use stranded copper or aluminum conductors, although small power cables may use solid conductors. The cable may include uninsulated conductors used for the circuit neutral or for ground (earth) connection.