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[[Image:Cat 5.jpg|thumb|300px|Category 5 [[patch cable]] in [[TIA/EIA-568-B]] wiring]]
[[Image:Cat 5.jpg|thumb|300px|Category 5 [[patch cable]] in [[TIA/EIA-568-B]] wiring]]
'''Category 5 cable''' ('''Cat 5''') is a [[twisted pair]] high signal integrity cable type. This type of cable is used in [[structured cabling]] for [[computer network]]s such as [[Ethernet]] and [[Asynchronous Transfer Mode|ATM]], and is also used to carry many other signals such as Analogue and Digital. Most of the time cable is connected using a RJ-45 connector Most Category 5 cables are [[Electromagnetic shielding|unshielded]] (UTP), relying on the twisted pair design for noise rejection. Category 5 has been superseded by the '''Category 5e''' specification.
'''Category 5 cable''' ('''Cat 5''') is a [[twisted pair]] high signal integrity cable type. This type of cable is used in [[structured cabling]] for [[computer network]]s such as [[Ethernet]] and [[Asynchronous Transfer Mode|ATM]], and is also used to carry many other signals such as [[telephony]] and [[video]]. Most Category 5 cables are [[Electromagnetic shielding|unshielded]] (UTP) using RJ-45 connectors, relying on the twisted pair design for noise rejection. Category 5 has been superseded by the '''Category 5e''' specification.


{|style="float:right; clear:right"
{|style="float:right; clear:right"
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The specification for Category 5 cable was defined in [[American National Standards Institute|ANSI]]/[[EIA 568A|TIA/EIA-568-A]], with clarification in TSB-95. These documents specified performance characteristics and test requirements for [[frequencies]] of up to 100 MHz.
The specification for Category 5 cable was defined in [[American National Standards Institute|ANSI]]/[[EIA 568A|TIA/EIA-568-A]], with clarification in TSB-95. These documents specified performance characteristics and test requirements for [[frequencies]] of up to 100 MHz.


Category 5<ref name="tiaonline_org-2522T5FQR2224200A">{{cite web|title=Category 5 - TIA's Glossary of Telecommunication Terms|url=http://www.tiaonline.org/market_intelligence/glossary/index.cfm?term=%25%22T%5FQR%22%24%20%0A}} 090524 tiaonline.org</ref> cable is not limited to 4 pairs. Backbone applications involve using up to 100 pairs as noted in ANSI/TIA/EIA-568-B-2 standard for backbone applications. This use of [[balanced line]]s helps preserve a high signal-to-noise ratio despite interference from both external sources and other pairs (this latter form of interference is called [[crosstalk]]). It is most commonly used for 100 Mbit/s networks, such as 100BASE-TX [[Ethernet]], although [[IEEE 802.3]]ab defines standards for 1000BASE-T – [[Gigabit Ethernet]] over category 5 cable. Each of the four pairs in a Cat 5 cable has differing precise number of twists per metre based on [[prime numbers]] to minimize crosstalk between the pairs. On average there are 6 twists per 5 centimetres.<!-- 3tw/inch --> The pairs are made from 24 [[American wire gauge|gauge]] (AWG) copper wires within the cables.
Category 5<ref name="tiaonline_org-2522T5FQR2224200A">{{cite web|title=Category 5 - TIA's Glossary of Telecommunication Terms|url=http://www.tiaonline.org/market_intelligence/glossary/index.cfm?term=%25%22T%5FQR%22%24%20%0A}} 090524 tiaonline.org</ref> cable is not limited to 4 pairs. Backbone applications involve using up to 100 pairs as noted in ANSI/TIA/EIA-568-B-2 standard for backbone applications. This use of [[balanced line]]s helps preserve a high signal-to-noise ratio despite interference from both external sources and other pairs (this latter form of interference is called [[crosstalk]]). It is most commonly used for 100 Mbit/s networks, such as 100BASE-TX [[Ethernet]], although [[IEEE 802.3]]ab defines standards for 1000BASE-T - [[Gigabit Ethernet]] over category 5 cable. Each of the four pairs in a Cat 5 cable has differing precise number of twists per metre based on [[prime numbers]] to minimize crosstalk between the pairs. On average there are 6 twists per 5 centimetres.<!-- 3tw/inch --> The pairs are made from 24 [[American wire gauge|gauge]] (AWG) copper wires within the cables.


==Connectors and other information==
==Connectors and other information==
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!ref
!ref
|-
|-
|[[Characteristic impedance]] @ 100 [[Hertz|MHz]]||align="right"|100||± 15||{{nowrap|[[Ohm|Ω]]}}||{{nowrap|<ref name="drakacom_cat5">{{cite web|title=SuperCat OUTDOOR CAT 5e U/UTP|url=http://communications.draka.com/sites/eu/Datasheets/SuperCat5_24_U_UTP_Install.pdf}} 080319 draka.com</ref>}}
|[[Characteristic impedance]] @ 100 [[Hertz|MHz]]||align="right"|100||+- 15||{{nowrap|[[Ohm|W]]}}||{{nowrap|<ref name="drakacom_cat5">{{cite web|title=SuperCat OUTDOOR CAT 5e U/UTP|url=http://communications.draka.com/sites/eu/Datasheets/SuperCat5_24_U_UTP_Install.pdf}} 080319 draka.com</ref>}}
|-
|-
|[[Real versus nominal value|Nominal]] characteristic [[Electrical impedance|impedance]] @ 100 [[Hertz|MHz]]||align="right"|100||± 5||{{nowrap|[[Ohm|Ω]]}}||{{nowrap|<ref name="drakacom_cat5" />}}
|[[Real versus nominal value|Nominal]] characteristic [[Electrical impedance|impedance]] @ 100 [[Hertz|MHz]]||align="right"|100||+- 5||{{nowrap|[[Ohm|W]]}}||{{nowrap|<ref name="drakacom_cat5" />}}
|-
|-
|[[Copper cable certification#DC Loop Resistance|DC-Loop resistance]]||align="right"|≤ 0.188|| ||{{nowrap|[[Ohm|Ω]]/[[Meter|m]]}}||{{nowrap|<ref name="drakacom_cat5" />}}
|[[Copper cable certification#DC Loop Resistance|DC-Loop resistance]]||align="right"|=< 0.188|| ||{{nowrap|[[Ohm|W]]/[[Meter|m]]}}||{{nowrap|<ref name="drakacom_cat5" />}}
|-
|-
|[[Propagation speed]]||align="right"|0.64|| ||[[Speed of light|c]]||{{nowrap|<ref name="drakacom_cat5" />}}
|[[Propagation speed]]||align="right"|0.64|| ||[[Speed of light|c]]||{{nowrap|<ref name="drakacom_cat5" />}}
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|Max tensile load, during installation||align="right"|100|| ||{{nowrap|[[Newton (unit)|N]]}}||{{nowrap|<ref name="drakacom_cat5" />}}
|Max tensile load, during installation||align="right"|100|| ||{{nowrap|[[Newton (unit)|N]]}}||{{nowrap|<ref name="drakacom_cat5" />}}
|-
|-
|Wire size||align="right"|[[American wire gauge|AWG]]-24 {{nowrap|(0.205 mm² <!-- The drakacom_cat5 cable datasheet specifies AWG-24. The powerstream_awg reference table gives for AWG-24 diameter=0.0201 inches. 0.0201"/(100/2.54)=0.511 mm. Formula A=pi*r² with inserted values pi*((0.0201/(100/2.54))/2)**2 * 1000*1000 gives 0.205 mm². Difference is 3.8% from previous edit, so any insight on this would be interesting ;) -->)}} || || ||{{nowrap|<ref name="drakacom_cat5" /><ref name="powerstream_awg" />}}
|Wire size||align="right"|[[American wire gauge|AWG]]-24 {{nowrap|(0.205 mm^2 <!-- The drakacom_cat5 cable datasheet specifies AWG-24. The powerstream_awg reference table gives for AWG-24 diameter=0.0201 inches. 0.0201"/(100/2.54)=0.511 mm. Formula A=pi*r^2 with inserted values pi*((0.0201/(100/2.54))/2)**2 * 1000*1000 gives 0.205 mm^2. Difference is 3.8% from previous edit, so any insight on this would be interesting ;) -->)}} || || ||{{nowrap|<ref name="drakacom_cat5" /><ref name="powerstream_awg" />}}
|-
|-
|Insulation thickness||align="right"|0.245<!--The drakacom_cat5 cable datasheet specifies wire diameter to 1.0 mm with PE insulator. So insulator radius minus conductor radius with values gives (0.0010/2 - (0.0201"/(100/2.54))/2) = 0.245 mm-->|| ||[[Millimetre|mm]]||{{nowrap|<ref name="drakacom_cat5" />}}
|Insulation thickness||align="right"|0.245<!--The drakacom_cat5 cable datasheet specifies wire diameter to 1.0 mm with PE insulator. So insulator radius minus conductor radius with values gives (0.0010/2 - (0.0201"/(100/2.54))/2) = 0.245 mm-->|| ||[[Millimetre|mm]]||{{nowrap|<ref name="drakacom_cat5" />}}
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|Maximum current per conductor||align="right"|0.577|| ||{{nowrap|[[Ampere|A]]}}||{{nowrap|<ref name="powerstream_awg">{{cite web|title=American Wire Gauge table and AWG Electrical Current Load Limits|url=http://www.powerstream.com/Wire_Size.htm}} 081220 powerstream.com</ref>}}
|Maximum current per conductor||align="right"|0.577|| ||{{nowrap|[[Ampere|A]]}}||{{nowrap|<ref name="powerstream_awg">{{cite web|title=American Wire Gauge table and AWG Electrical Current Load Limits|url=http://www.powerstream.com/Wire_Size.htm}} 081220 powerstream.com</ref>}}
|-
|-
|Temperature operating||align="right"|-55 to +60|| ||{{nowrap|[[Celsius|°C]]}}||{{nowrap|<ref name="drakacom_cat5" />}}
|Temperature operating||align="right"|-55 to +60|| ||{{nowrap|[[Celsius|DEGC]]}}||{{nowrap|<ref name="drakacom_cat5" />}}
|}
|}


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CMR ('''C'''o'''m'''munications '''R'''iser), insulated with high-density polyolefin and jacketed with low-smoke polyvinyl chloride (PVC) can be replaced by a CMP ('''C'''o'''m'''munications '''P'''lenum), insulated with flourinated ethylene propylene (FEP) and polyethylene (PE) and jacketed with low-smoke polyvinyl chloride (PVC), due to better flame test ratings. CM ('''C'''o'''m'''munications) is insulated with high-density polyolefin, but not jacketed with PVC and therefore is the lowest of the three in flame resistance.<ref name="74_125_77_132-inc_php_3Finc_3Dinfo-CSA-Flame-Test-Ratings_hl_sv_ct_clnk_cd_2" />
CMR ('''C'''o'''m'''munications '''R'''iser), insulated with high-density polyolefin and jacketed with low-smoke polyvinyl chloride (PVC) can be replaced by a CMP ('''C'''o'''m'''munications '''P'''lenum), insulated with flourinated ethylene propylene (FEP) and polyethylene (PE) and jacketed with low-smoke polyvinyl chloride (PVC), due to better flame test ratings. CM ('''C'''o'''m'''munications) is insulated with high-density polyolefin, but not jacketed with PVC and therefore is the lowest of the three in flame resistance.<ref name="74_125_77_132-inc_php_3Finc_3Dinfo-CSA-Flame-Test-Ratings_hl_sv_ct_clnk_cd_2" />


Some cables are "UV rated" or "UV stable" meaning they can be exposed to outdoor [[Ultraviolet|UV]] radiation without significant destruction. The materials used for the mantle are usually [[Polyvinyl chloride|PVC]].<ref name="broadbandreports_com-remark_16168746">{{cite web|title=CAT5e CMR/CMX mean it's uv rated ? - dslreports.com|url=http://www.broadbandreports.com/forum/remark,16168746}} 090126 broadbandreports.com</ref><!--Any document stating the UV [nm] spectrum, intensity [Watt/meter²], exposure time [hours] would be useful. Rather than just the loose term "UV rated"-->
Some cables are "UV rated" or "UV stable" meaning they can be exposed to outdoor [[Ultraviolet|UV]] radiation without significant destruction. The materials used for the mantle are usually [[Polyvinyl chloride|PVC]].<ref name="broadbandreports_com-remark_16168746">{{cite web|title=CAT5e CMR/CMX mean it's uv rated ? - dslreports.com|url=http://www.broadbandreports.com/forum/remark,16168746}} 090126 broadbandreports.com</ref><!--Any document stating the UV [nm] spectrum, intensity [Watt/meter^2], exposure time [hours] would be useful. Rather than just the loose term "UV rated"-->


Any cable which contains air spaces can breathe in moisture, especially if the cable runs between indoor and outdoor spaces. Warm moist air can cause condensation inside the colder parts of the cable outdoors. It may be necessary to take precautions such as sealing the ends of the cables. Some cables are suitable for "direct burial", but this usually requires that the cable be gel filled in order to hinder moisture migration into the cable.<!--Documents stating gel material, and moisture parameters would be useful, like how much water pressure would a cable withstand-->
Any cable which contains air spaces can breathe in moisture, especially if the cable runs between indoor and outdoor spaces. Warm moist air can cause condensation inside the colder parts of the cable outdoors. It may be necessary to take precautions such as sealing the ends of the cables. Some cables are suitable for "direct burial", but this usually requires that the cable be gel filled in order to hinder moisture migration into the cable.<!--Documents stating gel material, and moisture parameters would be useful, like how much water pressure would a cable withstand-->
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The American market was flooded with [[Cladding (metalworking)|copper clad]] cable imported mostly from China and falsely presented in the market as being a 100% copper Cat 5e cable. With less copper involved in the manufacturing process, the cost to the consumer is lower, yet the consumer is not getting a true 100% copper Cat 5e cable.
The American market was flooded with [[Cladding (metalworking)|copper clad]] cable imported mostly from China and falsely presented in the market as being a 100% copper Cat 5e cable. With less copper involved in the manufacturing process, the cost to the consumer is lower, yet the consumer is not getting a true 100% copper Cat 5e cable.


Installation of copper clad aluminium Cat 5e wire was proven — by low-voltage contractors in the Southern California market, where this cable first arrived — to have poor test results and often did not pass the Category 5e transmission standard. Since copper conducts electricity better than aluminium, signal strength has shown to be very weak over long runs using this substandard cable.
Installation of copper clad aluminium Cat 5e wire was proven - by low-voltage contractors in the Southern California market, where this cable first arrived - to have poor test results and often did not pass the Category 5e transmission standard. Since copper conducts electricity better than aluminium, signal strength has shown to be very weak over long runs using this substandard cable.


Additionally, some manufacturers falsely represented their Cat 5e cable conductors as being 24 [[American wire gauge|AWG]]. In actuality, a 26 AWG conductor is being sold and is hard to detect unless further examination beneath the sheath of the conductor is performed. A 26 AWG Cat 5e cable will not make proper contact on Cat 5e jack modules as most jack modules require 22 or 24 AWG per the specification and qualified connectors.<ref name="yahoo_store-File0003">{{cite web|title=Cat5E 90 deg HD Data Jack Module|url=http://lib.store.yahoo.net/lib/yhst-62665683816747/File0003.pdf}} 090901 lib.store.yahoo.net TIA/EIA-568-B.2 compliant data jack</ref>
Additionally, some manufacturers falsely represented their Cat 5e cable conductors as being 24 [[American wire gauge|AWG]]. In actuality, a 26 AWG conductor is being sold and is hard to detect unless further examination beneath the sheath of the conductor is performed. A 26 AWG Cat 5e cable will not make proper contact on Cat 5e jack modules as most jack modules require 22 or 24 AWG per the specification and qualified connectors.<ref name="yahoo_store-File0003">{{cite web|title=Cat5E 90 deg HD Data Jack Module|url=http://lib.store.yahoo.net/lib/yhst-62665683816747/File0003.pdf}} 090901 lib.store.yahoo.net TIA/EIA-568-B.2 compliant data jack</ref>
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[[af:Kategorie 5 kabel]]
[[af:Kategorie 5 kabel]]
[[ar:كابل مجموعة 5]]
[[ar:k+a+b+l+ m+g+m+w+e+tm 5]]
[[de:Cat-5-Kabel]]
[[de:Cat-5-Kabel]]
[[el:Καλώδιο κατηγορίας 5]]
[[el:Kalw%dio katygori%a*s 5]]
[[es:Cable de Categoría 5]]
[[es:Cable de Categoria 5]]
[[fr:Câble catégorie 5]]
[[fr:Cable categorie 5]]
[[ja:KaTeGoRi-65Ke-6BuRu]]
[[ja:カテゴリー5ケーブル]]
[[mk:Category 5 cable]]
[[mk:Category 5 cable]]
[[no:Kategori 5-kabel]]
[[no:Kategori 5-kabel]]

Revision as of 11:42, 12 May 2011

Category 5 patch cable in TIA/EIA-568-B wiring

Category 5 cable (Cat 5) is a twisted pair high signal integrity cable type. This type of cable is used in structured cabling for computer networks such as Ethernet and ATM, and is also used to carry many other signals such as telephony and video. Most Category 5 cables are unshielded (UTP) using RJ-45 connectors, relying on the twisted pair design for noise rejection. Category 5 has been superseded by the Category 5e specification.

8P8C modular plug pin positioning
TIA/EIA-568-A.1-2001 T568A Wiring
Pin Pair Wire Color
1 3 1 Pair 3 Wire 1 white/green
2 3 2 Pair 3 Wire 2 green
3 2 1 Pair 2 Wire 1 white/orange
4 1 2 Pair 1 Wire 2 blue
5 1 1 Pair 1 Wire 1 white/blue
6 2 2 Pair 2 Wire 2 orange
7 4 1 Pair 4 Wire 1 white/brown
8 4 2 Pair 4 Wire 2 brown
TIA/EIA-568-B.1-2001 T568B Wiring[1]
Pin Pair Wire Color
1 2 1 Pair 2 Wire 1 white/orange
2 2 2 Pair 2 Wire 2 orange
3 3 1 Pair 3 Wire 1 white/green
4 1 2 Pair 1 Wire 2 blue
5 1 1 Pair 1 Wire 1 white/blue
6 3 2 Pair 3 Wire 2 green
7 4 1 Pair 4 Wire 1 white/brown
8 4 2 Pair 4 Wire 2 brown
USOC/RJ61 Wiring
Pin Pair Wire Color
1 4 tip Pair 4 Wire 1 white/brown
2 3 tip Pair 3 Wire 1 white/green
3 2 tip Pair 2 Wire 1 white/orange
4 1 ring Pair 1 Wire 2 blue
5 1 tip Pair 1 Wire 1 white/blue
6 2 ring Pair 2 Wire 2 orange
7 3 ring Pair 3 Wire 2 green
8 4 ring Pair 4 Wire 2 brown
Partially stripped cable showing the twisted pairs.
A Cat 5e Wall outlet showing the two wiring schemes: A for T568A, B for T568B.

Cable standard

The specification for Category 5 cable was defined in ANSI/TIA/EIA-568-A, with clarification in TSB-95. These documents specified performance characteristics and test requirements for frequencies of up to 100 MHz.

Category 5[2] cable is not limited to 4 pairs. Backbone applications involve using up to 100 pairs as noted in ANSI/TIA/EIA-568-B-2 standard for backbone applications. This use of balanced lines helps preserve a high signal-to-noise ratio despite interference from both external sources and other pairs (this latter form of interference is called crosstalk). It is most commonly used for 100 Mbit/s networks, such as 100BASE-TX Ethernet, although IEEE 802.3ab defines standards for 1000BASE-T - Gigabit Ethernet over category 5 cable. Each of the four pairs in a Cat 5 cable has differing precise number of twists per metre based on prime numbers to minimize crosstalk between the pairs. On average there are 6 twists per 5 centimetres. The pairs are made from 24 gauge (AWG) copper wires within the cables.

Connectors and other information

The cable exists in both stranded and solid conductor forms. The stranded form is more flexible and withstands more bending without breaking and is suited for reliable connections with insulation piercing connectors, but makes unreliable connections in insulation-displacement connectors (IDCs). The solid form is less expensive and makes reliable connections into insulation displacement connectors, but makes unreliable connections in insulation piercing connectors. Taking these things into account, building wiring (for example, the wiring inside the wall that connects a wall socket to a central patch panel) is solid core, while patch cables (for example, the movable cable that plugs into the wall socket on one end and a computer on the other) are stranded. Outer insulation is typically PVC or LSOH.

Cable types, connector types and cabling topologies are defined by TIA/EIA-568-B. Nearly always, 8P8C modular connectors, often incorrectly referred to as "RJ-45", are used for connecting category 5 cable. The specific category of cable in use can be identified by the printing on the side of the cable.[3]

The cable is terminated in either the T568A scheme or the T568B scheme. Canada and Australia use the T568A standard, and the United States commonly uses T568B scheme. It really doesn't make any difference which is used as long as you use only one of the standards so all connections are the same at your location to avoid confusion and potential problems. Mixed cable types should not be connected in series as the impedance per pair differs slightly and may cause signal degradation. The article Ethernet over twisted pair describes how the cable is used for Ethernet, including special "cross over" cables. The USOC/RJ-61 standard is used in multi-line telephone connections.

Conductors required

10BASE-T (IEEE) and 100BASE-TX (IEEE) Ethernet connections require two cable pairs. 1000BASE-T (IEEE) and 1000BASE-TX (TIA/EIA-854, requiring category 6 cabling) Ethernet connections require four cable pairs. Four pair cable is by far the most commonly available type.

Bending radius

Most Cat 5 cables can be bent at a radius approximately 4 times the diameter of the cable.[4]

Maximum cable segment length

According to the ANSI/TIA/EIA standard for category 5e cable, (TIA/EIA 568-5-A[5]) the maximum length for a cable segment is 100 meters (328 feet). If longer runs are required, the use of active hardware such as a repeater, or a switch, is necessary.[6] [7] The specifications for 10baseT networking specify a 100 metre length between active devices. This allows for 90 metres of fixed cabling, two connectors and two patch leads of 5 metres, one at each end. In practice longer lengths are possible. (See Ethernet over twisted pair which states that 150 m is often considered to be the maximum working length.) Experiments show that a full 305 metre drum of cable is well above the practical limit, but that reliable transmission with 200 m is often possible.

Characteristics

Electrical characteristics for Cat 5e UTP
Property Nominal Value Tolerance Unit ref
Characteristic impedance @ 100 MHz 100 +- 15 W [8]
Nominal characteristic impedance @ 100 MHz 100 +- 5 W [8]
DC-Loop resistance =< 0.188 W/m [8]
Propagation speed 0.64 c [8]
Propagation delay 4.80-5.30 ns/m [8]
Delay skew < 100 MHz < 0.20 ns/m [8]
Capacitance at 800 Hz 52 pF/m [8]
Inductance 525 nH/m [9]
Cutoff frequency 50323 Hz [9]
Max tensile load, during installation 100 N [8]
Wire size AWG-24 (0.205 mm^2 ) [8][10]
Insulation thickness 0.245 mm [8]
Maximum current per conductor 0.577 A [10]
Temperature operating -55 to +60 DEGC [8]

Dielectric

Example materials used as dielectric in the cable[11]
Acronym Material
PVC Polyvinyl Chloride
PE Polyethylene
FP Foamed polyethylene
FEP Teflon/fluorinated ethylene propylene
FFEP Foamed Teflon/fluorinated ethylene propylene
AD/PE Air dielectric/polyethylene

Individual twist lengths

By altering the length of each twist, crosstalk is reduced, without affecting the characteristic impedance.[9][dubious – discuss]

   Pair color [cm] per turn Turns per [m]
Green 1.53 65.2
Blue 1.54 64.8
Orange 1.78 56.2
Brown 1.94 51.7

Environmental ratings

US & Canada fire certifications[12][13]
Class Phrase Standards
CMP Communications Plenum CSA FT7[14] or NFPA 262[14] (UL 910)
CMR Communications Riser UL 1666
CMG Communications General purpose CSA FT4
CM Communications UL 1685 (UL 1581, Sec. 1160) Vertical-Tray
CMX Communications Residential UL 1581, Sec. 1080 (VW-1)
CMH CSA FT1

CMR (Communications Riser), insulated with high-density polyolefin and jacketed with low-smoke polyvinyl chloride (PVC) can be replaced by a CMP (Communications Plenum), insulated with flourinated ethylene propylene (FEP) and polyethylene (PE) and jacketed with low-smoke polyvinyl chloride (PVC), due to better flame test ratings. CM (Communications) is insulated with high-density polyolefin, but not jacketed with PVC and therefore is the lowest of the three in flame resistance.[12]

Some cables are "UV rated" or "UV stable" meaning they can be exposed to outdoor UV radiation without significant destruction. The materials used for the mantle are usually PVC.[15]

Any cable which contains air spaces can breathe in moisture, especially if the cable runs between indoor and outdoor spaces. Warm moist air can cause condensation inside the colder parts of the cable outdoors. It may be necessary to take precautions such as sealing the ends of the cables. Some cables are suitable for "direct burial", but this usually requires that the cable be gel filled in order to hinder moisture migration into the cable.

When using a cable for a tower, attention must be given to vertical cable runs which may channel water into sensitive indoor equipment.[16] This can often be solved by adding a drip-loop at the bottom of the run of cable.

Plenum rated cables are slower to burn and produce less smoke than cables using a mantle of materials like PVC. This also affects legal requirements for a fire sprinkler system. That is if a plenum rated cable is used, sprinkler requirement may be eliminated.[17]

Shielded cables (FTP/STP) are useful for environments where proximity to power cables, RF equipment, or high power equipment may introduce crosstalk, and can also be used where interference with radio receivers or where eavesdropping likelihood should be minimized.

Other issues

Copper-clad aluminium

Template:Globalize/USA The American market was flooded with copper clad cable imported mostly from China and falsely presented in the market as being a 100% copper Cat 5e cable. With less copper involved in the manufacturing process, the cost to the consumer is lower, yet the consumer is not getting a true 100% copper Cat 5e cable.

Installation of copper clad aluminium Cat 5e wire was proven - by low-voltage contractors in the Southern California market, where this cable first arrived - to have poor test results and often did not pass the Category 5e transmission standard. Since copper conducts electricity better than aluminium, signal strength has shown to be very weak over long runs using this substandard cable.

Additionally, some manufacturers falsely represented their Cat 5e cable conductors as being 24 AWG. In actuality, a 26 AWG conductor is being sold and is hard to detect unless further examination beneath the sheath of the conductor is performed. A 26 AWG Cat 5e cable will not make proper contact on Cat 5e jack modules as most jack modules require 22 or 24 AWG per the specification and qualified connectors.[18]

The United States Federal Government will not accept bids from China for Cat 5e cable due to China being absent from the Trade Agreements Act of 1979. In general, a product is only "TAA compliant" if it is made in the United States or a "Designated Country".

See also

References

  1. ^ "ANSI/TIA/EIA-568-B.1-2001 Approved: April 12, 2001 ; Commercial Building Telecommunications Cabling Standard Part 1: General Requirements" (PDF). 090917 nag.ru
  2. ^ "Category 5 - TIA's Glossary of Telecommunication Terms". 090524 tiaonline.org
  3. ^ "Ethernet Cable Identification and Use". Donutey. Retrieved 2011-04-01.
  4. ^ "Selecting coax and twisted-pair cable - Electronic Products". 081216 www2.electronicproducts.com
  5. ^ "The Evolution of Copper Cabling Systems from Cat5 to Cat5e to Cat6" (PDF).www.panduit.com
  6. ^ "UTP technology by Extron Technologies" (PDF). www.extron.com
  7. ^ "Cat5e Cable Wiring Schemes White Paper by B&B Electronics". bb-elec.com
  8. ^ a b c d e f g h i j k "SuperCat OUTDOOR CAT 5e U/UTP" (PDF). 080319 draka.com
  9. ^ a b c "Transmission Line Zo". 090113 prc68.com
  10. ^ a b "American Wire Gauge table and AWG Electrical Current Load Limits". 081220 powerstream.com
  11. ^ "UL Listed / ISO 9001 Compliant". 090127 unioncopper.com
  12. ^ a b "CSA Flame Test Ratings". 090126 74.125.77.132
  13. ^ "22Technical Information" (PDF).[dead link] 090126 belden.com
  14. ^ a b "The Flame Tests Conducted On A Cat6 Plenum Cable". Retrieved 2011-04-01.
  15. ^ "CAT5e CMR/CMX mean it's uv rated ? - dslreports.com". 090126 broadbandreports.com
  16. ^ "A dumb mistake a green WISP operator once made. - dslreports.com". 090126 broadbandreports.com
  17. ^ "What are the differences between PVC, riser and plenum rated cables? - Ask or Answer Questions on Computers & Technology, Ask & Read old Answers on Computers & Technology - ibibo sawaal". 090126 sawaal.ibibo.com
  18. ^ "Cat5E 90 deg HD Data Jack Module" (PDF). 090901 lib.store.yahoo.net TIA/EIA-568-B.2 compliant data jack
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