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As you can see, the wiring diagrams imprinted on the jacks show both the A & B wiring methods. The back of the patch panel also shows both wiring methods, as seen below.
 The upper diagram is 568A, and the lower diagram is 568B. Notice that the Blue and Brown pairs are identical for both methods. Only the Orange and Green pairs are interchanged from the A to the B method.
It’s important to note that there is absolutely no difference between the two wiring schemes in terms of performance when connected from one modular device to another (jack to patch panel, RJ45 to RJ45, etc.) so long as the two devices are wired for the same scheme (pins 1 through 8 on one end are connected to pins 1 through 8 on the other end). The only time one scheme has an advantage over the other is when one end of a network link is connected to a modular device, and the other end to a punch block. In this case, the 568A wiring scheme provides a more natural progression of pairs at the punch block. The TIA-568 standards committee decided to allow both wiring methods (568A & 568B) to exist within the 568B standard. This was done because many existing cabling plants were installed to the B standard (formerly known as WECO or AT&T 258A), and yet the standard recommends the 568A wiring scheme as the preferred method for all new installations. However, popular opinion went in the other direction, and the most popular wiring method today remains 568B. In my opinion, having both methods does nothing but cause errors and confusion. So which wiring scheme to choose? As we stated earlier; there is no difference between the two wiring schemes in connectivity or performance, so it doesn’t really matter. However, if you are terminating one end onto a punch block, the A method has the advantage. The most critical aspect is that you choose one method and stick with it. I recommend to all installers that wherever feasible, they terminate a link on both the jack and patch panel sides, and then test for proper continuity. Many times an entire installation is terminated only for the installer to then discover that the two ends of the links were wired for different methods. This requires reterminating all of the cables on one end to correct the problem.
UTP Installation Do's and Don'ts.
Do Run all cables in a Star Configuration so that all network links are distributed from, or homerun to, one central hub. Visualize a wagon wheel where all of the spokes start from on central point, known as the hub of the wheel.
Do Keep Each cable run must be kept to a maximum of 295 feet (90 meters), so that with patch cords, the entire channel is no more than 328 feet (100 meters). This is a requirement of the standard.
Do Maintain the twists of the pairs as close as possible to the point of termination, or no more than 0.5"(one half inch) untwisted.
Do Not Skin off more than 1" of jacket when terminating UTP
Do Make only gradual bends in the cable where necessary to maintain the minimum bend radius of 4 times the cable diameter or approximately 1" radius (about the roundness of a half-dollar).
Do Not Allow the cable to be sharply bent, twisted, or kinked at any time. This can cause permanent damage to the geometry of the cable and cause transmission failures.
Do Dress the cables neatly with Velcro cable ties, using low to moderate pressure.
Do Not Over tighten cable ties or use plastic ties.
Do Cross-connect cables (where necessary), using appropriately rated punch blocks and components.
Do Not Splice or bridge UTP cable at any point. There should never be multiple appearances of cable.
Do Use low to moderate force when pulling cable. The standard calls for a maximum of 25 lbf (pounds of force).
Do Not Use excessive force when pulling cable.
Do Use cable pulling lubricant for cable runs that may otherwise require great force to install. (You will be amazed at what a difference the cable lubricant will make)
Do Not Use oil or any other lubricant not specifically designed for UTP network cable pulling as they can infiltrate the cable jacket, causing damage to the insulation.
Do Keep UTP cables as far away from potential sources of EMI (electrical cables, transformers, light fixtures, etc.) as possible. Cables should maintain a 12-inch separation from power cables.
Do Not Tie cables to electrical conduits, or lay cables on electrical fixtures.
Do Install proper cable supports, spaced no more than 5 feet apart.
Do Not Install cable that is supported by the ceiling tiles. This is unsafe, and is a violation of the building codes.
Do Always label every termination point at both ends. Use a unique number for each network link. This will make moves, adds, changes, and troubleshooting as simple as possible. The TIA-606A administration standard provides guidance for properly labeling an installation.
Do Always test every installed segment with a cable tester. "Toning" alone is not an acceptable test.. "Toning" alone, is not an acceptable test.
Do Always install jacks in such a way as to prevent dust and other contaminants from settling on the contacts. The contacts (pins) of the jack should face up on flush mounted plates, or left, right, or down (never up) on surface mount boxes.
Do Always leave extra slack neatly coiled up in the ceiling or nearest concealed place. It is recommended that you leave at least 5 feet of slack at the work outlet end, and 10 feet of slack at the patch panel end.
Do Not Never install cables taught. A good installation should have the cables loose, but never sagging.
Do Always use grommets to protect cable when passing through metal studs or anything that can possibly cause damage.
Do Choose either 568A or 568B wiring scheme before you begin your project. Wire all jacks and patch panels for the same wiring scheme (A or B).
Do Not Mix 568A and 568B wiring on the same installation.
Do Not
(1 exception) Use staples on UTP cable that crimp the cable tightly. The common T-18 and T-25 cable staples are not recommended for UTP cable. However, the T-59 insulated staple gun is ideal for fastening both UTP and fiber optic cabling, as it does not put any excess pressure on the cable.
Do Always obey all local and national fire and building codes. Be sure to firestop all cables that penetrate a firewall. Use plenum rated cable where it is mandated.
| Key Definitions |
| UTP (Unshielded Twisted Pair) |
Used primarily for data transmission in local area networks (LANs), UTP network cable is a 4-pair, 100-ohm cable that consists of 4 unshielded twisted pairs surrounded by an outer jacket. Each pair is wound together for the purposes of canceling out noise that can interfere with the signal. UTP cabling systems are the most commonly deployed cable type in the U.S. |
| F/UTP (foil unshielded twisted pair) |
F/UTP cable consists of four unshielded twisted pairs surrounded by an overall foil shield. F/UTP has also been referred to as ScTP (screened twisted pair) and FTP (foiled twisted pair). F/UTP cable is not as common as UTP, but is sometimes deployed in environments where electromagnetic interference (EMI) is a significant concern. With shielded systems, the foil shield must maintain continuity throughout the entire system. |
| S/FTP (shielded foil twisted pair) |
S/FTP consists of four foil-shielded twisted pairs surrounded by an overall braided shield. This fully shielded cable is often referred to as PiMF (pairs in metal foil), or SSTP. It is the primary cable type deployed in Europe, but rarely seen in the U.S. With shielded systems, the foil shield must maintain continuity throughout the entire system. |
| Category 5 Cable |
Category 5e cable is an enhanced version of Category 5 that adheres to more stringent standards (see comparison chart below). It is capable of transmitting data at speeds of up to 1000 Mbps (1 Gigabit per second). |
| Category 6 Cable |
Category 6 cable was designed to perform at frequencies of up to 250 MHz and offers higher performance for better transmission of data at speeds up to 1000 Mbps (see comparison chart below). Some properly installed Category 6 cable will also support 10 Gigabit speeds, but likely with limitations on length (look for our upcoming Category 6A / 10 Gig tutorial). |
Augmented Category 6 (6A)
(Work Area Outlet) |
Category 6A cable is the latest twisted-pair cable type defined in February 2008 under the newest version of the TIA 568-B standard (568-B.2-10). Category 6A operates at frequencies of up to 500 MHz and can support transmission speeds at 10 Gigabits per second (Gbps). (Look for our upcoming Category 6A / 10 Gig tutorial.) |
| Category 7 |
Prior to Category 6A cable, Category 7 cable was designed to transmit data at 10-gigabit speeds. Category 7 cable is an F/STP (PiMF) cable that includes shielding for individual pairs and the cable as a whole. Category 7 is terminated with RJ-45 compatible GG45 connectors or TERA connectors, and it is rated for transmission frequencies up to 600 MHz. This cable type is rarely installed in the U.S. |
| RJ45 Jack |
The RJ45 jack is an 8-conductor, compact, modular jack used to terminate UTP data cable. RJ45 jacks are engineered to maintain specific Category 5, 5e, 6, or 6A performance, and therefore must match the category of the cable they are terminating. |
| Patch Panel |
A Patch Panel is a series of RJ45 jacks condensed onto a single panel. Common panel configurations include 12, 24, 48, and 96 ports. Patch panels are typically deployed where horizontal cables converge, and are used to interconnect or crossconnect links to a network switch or hub. |
| Patch Cable |
A Patch Cable is a cable assembly that consists of a length of UTP cable with an RJ45 male connector crimped onto each end. This cable assembly is used to provide connectivity between any two RJ45 jacks. The two most common uses for patch cables are for connecting patch panel ports to other patch panel ports or to switch ports, and for connecting the work area outlet (jack) to the computer or other networked device. |
| Star Configuration |
In a Star Topology, network links are distributed from one central switch or hub. This configuration provides and easy-to-understand layout, offers a centralized management point, and ensures that if one network link fails, all others can still function. |
| ANSI/EIA/TIA-568B Standard |
This standard was published in 2001 to replace the 568A standard, which is now obsolete. The original purpose of the EIA/TIA 568 standard was to create a multiproduct, multivendor, standard for interoperable connectivity. The 568B standard sets minimum requirements for the various categories of cabling. The most recent version of the 568B standard (568B.2-10) published in February 2008 defines the requirements of twisted-pair cabling to support 10 Gigabit transmission. The 568 "standard" is not to be confused with 568A or 568B wiring schemes. |
| 568A and 568B Wiring Schemes |
When we refer to a jack or a patch panel's wiring connection, we refer to either the 568A or 568B wiring scheme, which define the pin-pair assignments for terminating UTP cable. The only difference between 568A and 568B is that pairs 2 and 3 (orange and green) are swapped. For more information, see the following section on wiring schemes. |
| Bend Radius |
Bend radius is the minimum radius a cable can be bent without kinking it, damaging it, or shortening its life. The minimum bend radius for Category 5, 5e, and 6 cable is four times the cable diameter, which is approximately 1 inch. When cabling is bent beyond this specified minimum bend radius, it can cause transmission failures. All pathways must maintain the minimum bend radius wherever the cable makes a bend. |
| Firestopping |
Firestopping is the sealing of holes made in fire walls and floors during cable installation. Firestopping materials and products are designed to restore the fire rating to what it was before penetrating the wall or floor. |
| Wiremap |
This is the most basic test that can be performed on a UTP network link. Wiremap tests for continuity between two devices. Whether using 568A or 568B wiring scheme, all eight pins of each device should be wired straight through (pins 1 through 8 on one end are connected to pins 1 through 8 on the other end). A wiremap test also tests for opens, shorts, grounding, and external voltage. |
| Crosstalk |
Crosstalk is the "bleeding" of signals from one pair in a cable onto another pair through induction (wires need not make contact because signals are transferred magnetically). Crosstalk is an unwanted effect that can cause slow data transfer, or completely inhibit the transfer of data signals. Crosstalk is minimized by the twisting of the pairs in the cable. Fiber Optic cable is the only cable medium that is 100% immune to the effects of crosstalk or EMI. |
| Electromagnetic Interference (EMI) |
Similar to crosstalk, EMI is an unwanted signal that is induced into the cable. The difference is that EMI typically comes from a source that is external to the cable, such as an electrical cable or device. |
| Near-end Crosstalk (NEXT) |
NEXT is a testing parameter that measures the crosstalk from an interfering pair transmitting at the same end of a network link. |
| Far-end Crosstalk (FEXT) |
FEXT is a testing parameter that measures the crosstalk from an interfering pair transmitting from the other end of the link. FEXT is measured as Equal Level FEXT (ELFEXT), which compensates for attenuation by subtracting it from the interfering pair. |
| Power Sum NEXT (PSNEXT) |
PSNEXT is the sum of the NEXT induced on a pair from all other adjacent pairs. PSNEXT is a more stringent measurement than NEXT because it measures the total possible crosstalk from multiple pairs in the same cable, not just the crosstalk from one pair to another pair. PSNEXT is only critical in high-speed networks that transmit data over multiple pairs. |
| Power Sum ELFEXT (PSELFEXT) |
Like PSNEXT, PSELFEXT is the sum of the ELFEXT induced on a pair from all other adjacent pairs. PSELFEXT is only critical in high-speed networks that transmit data over multiple pairs. |
| Attenuation |
Attenuation is the loss of signal over the length of a network link due to the resistance of the wire plus other electrical factors that cause additional resistance (impedance and capacitance for example). A longer cable length, poor connections, bad insulation, a high level of crosstalk, or EMI can all increase attenuation. For each category of cable, the TIA-568B standard specifies the maximum amount of attenuation that is acceptable in a network link. |
| Attenuation to Crosstalk Ratio (ACR) |
ACR is probably the most important result when testing a link. ACR is the difference between the signal attenuation and the near-end crosstalk, representing the strength of the attenuated signal in the presence of crosstalk. If ACR is not high enough, errors will occur or the data signal can be lost. Power Sum ACR (PSACR) is calculated in the same way as ACR, but uses the PSNEXT results rather than NEXT. |
| Return Loss |
Return Loss is the difference between the power of a transmitted signal and the power of the signal reflections caused by variations in link and channel impedance. |
| Propagation Delay |
Propagation Delay tests for the time it takes for the signal to be sent from one end of a link and received by the other end. |
| Delay Skew |
Only a critical parameter in high-speed networks that transmit data using multiple pairs, Delay Skew is the difference in time between the fastest arrival of a data signal on a pair and the slowest. Signals divided over multiple pairs need to reach the other end within a certain amount of time to be re-combined correctly. |
|
568B Standard
Published in 2001, the TIA-568B standard sets minimum requirements for the various categories of cabling. The 568 "standard" is not to be confused with 568A or 568B wiring schemes, which are themselves part of the standard. |
568A & 568B Wiring Schemes
When we refer to a jack or a patch panel's wiring connection, we refer to either the 568A or 568B wiring scheme, which define the pin-pair assignments for terminating UTP cable. |
CAT-5, CAT-5e, CAT-6, CAT-7 Patch Cables
FAQs
1. What is the difference between CAT-5, CAT-5e, CAT-6, CAT-7...
The Simple Answer:
CAT-5 is rated to 100M
CAT-5e is rated to 350M
CAT-6 and CAT6e is rated to 550M or 1000M depending on your source
CAT-7 is supposedly rated to 700M or presumably 1000M
Today there is no approved CAT-6 or CAT-7. While some folks are selling products they call Level 6 or 7, there aren't even specs for them, making CAT-5e the best available option. CAT-6 cable is being made with 23 guage conductor wire as opposed to the slightly smaller 24 guage for CAT-5e and also has a separator to handle crosstalk better.
Both CAT-5 and CAT-5e have 100 ohm impedance and electrical characteristics supporting transmissions up to 100 MHz. The differences between CAT-5 and CAT-5e show in all aspects of performance: capacitance, frequency, resistance, attenuation, and NEXT. CAT-5e components were designed with high-speed gigabit Ethernet in mind. While CAT-5 components may function to some degree in a gigabit Ethernet, they perform below standard during high-data transfer scenarios. CAT-5e cables work with ATM and gigabit speed products. Simply, if you are using a 100Mbps switch, get CAT-5e cable instead of CAT-5.
CAT-5e is formally called ANSI/TIA/EIA 568A-5 or simply Cat-5e (the e stands for 'enhanced'). CAT-5e is completely backward compatible with current CAT-5 equipment. The enhanced electrical performance of CAT-5e ensures that the cable will support applications that require additional bandwidth, such as gigabit Ethernet or analog video.
2. What is the difference between the types of cable - UTP, Patch, Stranded, Solid...
UTP stands for Unshielded Twisted Pair. It is a cable type with pairs of twisted insulated copper conductors contained in a single sheath. UTP cables are the most common type of cabling used in desktop communications applications.
Stranded cable has several small gauge wires in each separate insulation sleeve. Stranded cable is more flexible, making it more suitable for shorter distances, such as patch cords.
Solid has one larger gauge wire in each sleeve. Solid cable has better electrical performance than stranded cable and is traditionally used for inside walls and through ceilings - any type of longer run of cable.
Patch Cables are made of stranded copper conductors for flexibility. This construction is great for the flexing and the frequent changes that occur at the wall outlet or patch panel. The stranded conductors do not transmit data signals as far as solid cable. The TIA/EIA 568A which is the governing standard regarding commercial cabling systems limits the length of patch cables to 10 meters in total length. Does that mean you can't use stranded cable for longer runs? Not at all, we've seen installations running stranded cable over 100 feet with no problems - it's just not recommended. This is why we don't sell patch cables over 30 feet in length.
3. What is the difference between 10BASE-T, 100BASE-T and 1000BASE-T?
10BASE-T is the IEEE standard that defines the requirement for sending information at 10 Mbps on unshielded twisted-pair cabling, and defines various aspects of running Ethernet on this cabling.
100BASE-T is the IEEE standard that defines the requirement for sending information at 100 Mbps on unshielded twisted-pair cabling, and defines various aspects of running baseband Ethernet on this cabling.
1000BASE-T (also called gigabit Ethernet) is the IEEE standard that defines the requirement for sending information at 1000 Mbps on unshielded twisted-pair cabling, and defines various aspects of running baseband Ethernet on this cabling
Channel Performance Characteristics
Parameter |
CAT-5 (ISO Class D)100 MHz |
CAT-5 100 MHz |
CAT-5e 100 MHz |
Attenuation |
24.0dB |
24.0dB |
24.0dB |
NEXT |
27.1dB |
27.1dB |
30.1dB |
PSNEXT |
24.0dB |
N/A |
27.1dB |
ELFEXT |
17.0dB |
17.0dB |
17.4dB |
PSELFEXT |
14.4dB |
14.4dB |
14.4dB |
ACR (derived) |
3.1dB |
3.1dB |
6.1dB |
PSACR (derived) |
N/A |
N/A |
3.1dB |
Return Loss |
10.0dB |
8.0dB |
10.0dB |
4. What is a cross-over cable?
A cross-over cable is a segment of cable that crosses over pins 1&2 and 3&6. This cable is normally used to connect two PCs without the use of a hub, or can be used to cascade two hubs without using an uplink port. Some DSL modems require a crossover calbe to the PC or hub they are connected to.
5. What are the maximum lengths for cables?
For Solid UTP:
Fast Ethernet 100baseT 100 Meters (328 feet)
Twisted Pair Ethernet 10baseT 100 Meters (328 feet)
Recommended maximum lengths for Patch Cables made from stranded cable:
Fast Ethernet 100baseT 10 Meters (33 feet)
Twisted Pair Ethernet 10baseT 10 Meters (33 feet)
6. Is CAT-5e backwards compatible?
Yes it works with any 10BaseT or 100BaseT network cards and hubs.
CAT-5 is also upwardly compatible with CAT-5e, however your network throughput will only be as fast as the slowest part.
7. Can I run CAT-5e ethernet cable outside?
CAT-5e cable is not rated for outdoor use, however it can generally be used without a problem. If possible, run the cable through some kind of conduit to prevent moisture or an attractive site for lightning to strike. You should be able to find gray PVC conduit suitable for cable at any hardware store. Remember, 100 Meters is your max distance, without some kind of hub, bridge or amplification.
8. What is the operating temp for CAT-5e cable?
Operating Temp for CAT-5e cable: -10C to 60C
9. What is the difference between T568A and T568B wiring?
T568A and T568B are the 2 wiring patterns for 8 position RJ45 modular plug, both permitted under the TIA/EIA 568A wiring standards document. The only difference between the two pattern is that the pairs 2 (orange) and 3 (green) are interchanged.
All our cables use T568B standards.
10. What are the UL levels of cable?
There are three levels. General Purpose: UL1581; Riser: UL1666; and Plenum UL910. These numbers are all fire and safety rated.
11. What is EMI and how can you prevent it?
EMI stands for Electro-Magnetic Interference. It is potentially harmful to your communications system because it can lead to signal loss and degrade the overall performance of high-speed, CAT-5e cabling. EMI is interference in signal transmission or reception and is caused by the radiation of electrical or magnetic fields which are present near power cables, heavy machinery, or fluorescent lighting.
Avoiding EMI is as simple as not laying your network cable within 12" of electrical cable, or if needed switching from UTP to more expensive shielded cable.
12. Just tell me what cable I need...
If you need patch cords up to 25 feet, use CAT-5e stranded cable for ease of flexibility.
If you are making linger runs or going through walls or ceilings, I'd go ahead and use the CAT-6 UTP (solid) cables - if that seems a bit expensive, then go with the CAT-5e UTP.
BELOW ARE THE SERVICES WE PROVIDE .. In ADELAIDE, and Regional South Australia.  TELEPHONE, NETWORK, COMPUTER DATA CABLING INSTALLATIONS
Data Cable Install Cat5E Cat6
Phone System Maintenance
Phone VOIP Network and VOIP Telephone Cabling
Fibre-Fiber Optic Installations
Network Hardware - Hubs, Switches & Routers etc.
Integrated Voice and Data Cabling
Telephone System Repair Service
Digital Phone System Maintenance Service
Cable Certifications
Computer Access Floors & Air Conditioning
Wall Mount Cabinets, Racks & Computer Cabinets.
Patch Panels 16 Port & 24 Port
LAN Network Cabling Trays, Cable Management Systems
Underground Conduit & Pit Installations
ELECTRICAL INSTALLATIONS
All types of Electrical Installations
Test and Tag electrical equipment
Switch board upgrades
Service & Maintenance
Exit & Emergency Lighting Maintenance
UPS Power Systems, PC UPS, Computer UPS
Electrical Rewiring, New Connections
Safety Switches
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