Certain types of telephone wiring use solid color insulation markings rather than This means it runs to the west, and that it is coming from the CO. One cable on the right has an orange tie, which means it runs to the north out of the pedestal. Many technicians also refer to them as Plastic Insulated Cable. One telephone wire line needs only two wires. below. Cookies are used on this website to give you the most relevant browsing experience by remembering your preferences and repeat visits. This required a unique tool for assembly. 6. si data available for standard lengths only. Telephone cables are always referred to by their pairs so there are always twice as many conductors in the cable as the pair count indicates - a 200 pair cable has 400 conductors, but is always called a "200 pair". with another. Shipping charges are calculated based on the shipping option you select, and is prepaid by you at the time of shipment. of units: 1 x 2 p, shi. can be wired for configurations such as RJ61C (4-pair) and RJ48C. This picture shows a conventional telephone extension socket correctly wired with the stripey cable. So I bought myself a telephone wire punch-down tool and a tone tracer to identify the correct pair of wires. Each pair can be used as a phone line, so in this example you can use this cable for up to four phone lines. would be best cutter, The Ideal Telecutter may be used for cutting up to (quantity) pair telephone cable, the primary designed use of the ? A large telephone exchange can have dozens of these cables coming into it. The first group of colors is: white, red, black, yellow, violet. 20 pair old model telephone cable color code D.B connection for wagon,, PLPC TV Science and Technology Topics How To Make RJ45 Network Patch Cables - Cat 5E and Cat 6 Tek Syndicate 5M. Conductor color code according to T568B and T568A; . The point is, you will probably encounter cables both with bandmarks and 2. all assemblies to be 100 % electronically tested for shorts and opens. only for jacks that are connected directly to phone company circuits. . For decades, the telephone industry has relied on an established Study with Quizlet and memorize flashcards containing terms like When cutting 200 pair telephone cable, a ? Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors. Mirror image telephone cable core constructions are available in 1200 pair or more cable designs, all of which use 100 pair super units. A young trainee on the telephone switchboard in 1951. It was the above-mentioned long-forgotten transformer. [5][6], In cables of more than 600 pairs, each of the 600-pair super binder group bundles is wrapped with a mylar binder ribbon, or string, matching the "tip" colors of the color code, starting with white. The cores of 5 star quads of a sub unit are counted according to the sequence of basic colours: The marker of units are identified with a red helix, the others with white or uncoloured. To help determine the pneumatic resistance of the commom types of telephone cables, System Studies has provided this cable identification chart. [2] Each wire is identified by the combination of two colors, one of which is the major color, and the second the minor color. Get the latest news, special offers and events from Anixter. For cables containing more than 600 pairs, a Super Unit Binder Color code is used to separate multiple Binder bundles. In 1891 the insulating material was changed to strips of waxed paper. Subsequent pairs (up to pair 10) use blue with each of the remaining colours in-turn (blue/orange, blue/green, blue/brown and blue/slate. The second group of colors is: blue, orange, green, brown, slate. The blue pair is connected as the primary telephone line. By clicking Yes, I Agree, you consent to the use of the cookies according to your choices in the Cookie Settings. PIC cables and T-Screens have a gel-filled insulation, so when PIC cables were introduced, it then became the standard to refer to the lead and paper cables as Air Core Cables. The vast majority of cables using the 4-Letter code are PIC cables. I bought a cheap phone plug crimper to make phone cords any length that clients wanted. Just like water pipes, these phone C-codes can in some cases be related to the type of material, but their main purpose is to identify the actual use of the cable, such as an aerial cable running pole to pole. The M210 . The names of most of the colors were taken from the conventional colors of the rainbow or optical spectrum, and in the electronic color code, which uses the same ten colors, albeit in a different order. Mr. Electrician is a Registered Trademark. pair count cable used in the Outside Plant (OSP) does not have bandmarks or If the pair count is marked as 6, then it is a 600 pair, not a 6 pair. Phase 1 wiring should be brown. Follow my telephone wiring colour code and things should work first time for you. This will cause the loop to close on itself and make a better connection. Using this method an installer can navigate pretty effectively in The insulating coverings of single cores of a star quad are marked with black rings. to confusion since the RJ designations refer to very specific USOC wiring Line 1 (primary phone line): blue and white-with-blue-stripe Line 2 (secondary line): orange and white-with-orange-stripe Install the Mounting Plate Remove the cover from the front of the phone jack, exposing the mounting plate and mounting screw holes. Shop phone cable and a variety of electrical products online at Lowes.com. The white wire with a blue stripe is terminated on the green Tip screw. Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. This C code was applied to fiber lines when they were first being installed in the early 1980s, and was partially meant to quickly identify fiber lines from the old copper lines. pulp-insulated cable in service, especially with high pair counts of 1,500 to 2,700 pairs. plug. For cables containing more than 600 pairs, a Super . TELEPHONE COLOR CODE FOR JACKS IN YOUR HOME, Electrical Terms, Definitions, & Equations. This helps the sound quality. Also, many old lead cables have been relabeled on some phone prints using the 4-letter code, but always beginning with the letters XX. Beginning around the late 1940s, that outer lead was now removed and replaced with various plastic coverings. pair group from another since they both will have the same sequence of pair . It is desirable for manufacturing purposes to combine four 25 pair groups into super units when cables have 900 pairs or more. It was invented by Alexander Graham Bell. 1st set of 2nd set of, Numbers*- Numbers-, Years Produced Pair Count Gauge Sheath Insulation, 1888-1891 52 18 lead/tin oiled cotton, 1891-1892 52 19 lead/tin waxed paper, 1892-1895 100 19 lead/tin waxed paper, 1895-1896 152 19 lead/tin waxed paper, 1896-1896 180 19 lead/tin waxed paper, 1896-1901 208 19 lead/tin waxed paper, 1901-1912 303 19 lead/tin waxed paper, 1901-1902 404 22 lead/tin waxed paper, 1902-1912 606 22 lead/tin waxed paper, 1912-1958 26 22 lead/tin/antimony waxed paper, 1912-1958 51 22 lead/tin/antimony waxed paper, 1912-1918 303 19 lead/tin/antimony waxed paper, 1912-1930s 909 22 lead/tin/antimony waxed paper, 1914-1930s 1212 24 lead/tin/antimony waxed paper, c.1915-1958 26 & 51 24 lead/tin/antimony waxed paper, 1918-1930s 455 19 lead/tin/antimony waxed paper, c.1925-1958 100 -1200 24 lead/tin/antimony waxed paper, 1930s 1958 100 900 22 lead/tin/antimony waxed paper, c.1940-1958 26-51-100 26 lead/tin/antimony waxed paper, c.1940-1958 26-70-100 19 lead/tin/antimony waxed paper, 1942 54 19 lead/tin/antimony waxed paper, 1950s 26 51 400 22 alum/poly waxed paper, 1950s 2400 26 alum/stl/poly waxed paper, PIC Cables (and many Paper cables) 1958 to present. Violet is the standard name in the telecommunications and electronics industry, but it is sometimes referred to as purple. Pictures, Descriptions, and Handy Tips from Working over 40 Years as an Electrician. phone line in a home come down to confusion over mating one color code scheme Normally, the first pair used for your telephone line is solid Orange, solid White. There is two color coding standard EIA/TIA 568A and EIA/TIA 568B. cable color codes wire color codes a 25 pair group of pairs and be able to tell one pair from another. This socket isconnected to thelatest solid colour coded BT internal cable (which oddly is the same colour code as very early BT cable). Using RJ terms often leads COLOR CODE REPEATS FOR EACH GROUP OF 25 PAIRS. All other sub- or main-units must be whipped with an, The quads of a sub-unit are to be counted according to the sequence of basic colours. 64 Every super bundle uses wrapping, colored with one of first three tip colors. An 8-position jack The cable with the green plastic tie runs in a general easterly direction. Please note you must use the correct inserter tool to push the wires in to the phone socket IDC connectors. Newer homes can have anything from Cat-3, 3-pair on up to Cat-5e, with 4-pairs, with the insulation colors being a combination of solid and solid with white for each wiring pair. (This paragraph is based Phase 3 wiring should be yellow. banded color codes. Description. frame wire and station wire. The Electronic Industries . 1308. In cables with more than 5 star quads, the sub- and main-units must, Consist of 5 star quads = 10 pairs (DA)(DA = double core or pair), Consist of 6 main-units, each of 50 pairs (DA), Consist of 15 main-units, each of 100 pairs (DA), F) Colour Code & Cable Make Up According to IEC 60708-1, Identification of basic sub-units, construction of 50 and 100 pair units, and cable cores of up to 100 pairs, Identification of basic units and cable core constructions for cables of more than 100 pairs - Numbered units, G) Colour Code & Cable Make Up According to GR-421, ICEA S-85-625 & ICEA S-84-608, For pairs numbering 1 through 25, the pair identification colours are outlined below. This system allows up to 600 pair RJ-11 connector wiring comes in two standard types. Good wire cutters are essential when cutting BT Dropwire.This cable is heavy duty to cope with any kind of weather. MrElectrician.TV does not use cookies to track your browsing activity, but its advertisers might. Cond. LEAD Produced from 1888 to the late 1940s. . The conductors of the pair were terminated in their respective elements of For the first time there was a true separation of sheath and jacket. PIC cables are the only phone cables that have plastic insulated conductors, though you would typically never see the exposed interior of a lead or paper cable anyway. 5. parts to be layer packaged. Other uncategorized cookies are those that are being analyzed and have not been classified into a category as yet. Paper cables were still used inside of the Central Office. Similarly, slate is a particular shade of gray. The following pictures show the standard BT Telephone Wiring Colour Code used with the BT NTE5 Master Socket. This includes "flat" cables, also known Armored telephone cable laying exposed on the beach where it crosses the river. 100 pair cat3 telephone bulk cable bulk color coded telephon. You can enter a full complex cable count that can be split into the cable type of your choice (common 25 pair, 100 pair bundle or 300 pair bundle). In 1887 a conference was held between a number of the different companies to establish standards. 8-position jack can be wired for RJ45S, RJ46S, and RJ47S. fmtp-06-d-08.77-01 pdf fmtp-06-d-08.77-01 revision c notes: 1. represents a critical dimension. 3. all assemblies to be 100 % hi-pot tested at 630v. A few cables are even produced with pair counts of 75, and 175. dantonthegreat_jr 2 yr. ago 4 (RING BAND) PAIR : COLOR : PAIR: COLOR: 1 : White-Blue paired with Blue-White : 14: Black-Brown paired with Brown-Black: 2 : The first number indicated the pair count, while the second number indicated the gauge of conductor used. The cable pairs are color coded as shown: Each pair consists of a colored wire and a white wire with a matching color stripe. PIC cables are produced in pair counts of 25, so their sizes are 25, 50, 75, 100, 200, etc. Neither of these two sides of the line has a connection to the local ground. Phone: 1-888-651-9990. Checking the air pressure on a phone cable in 1958. For cables of 100-pair or less, the White binder is optional. This system allows up to 600 pair cables (violet/slate binders are never used; 25 pairs x 24 units = 600 pair) to be made. Analytical cookies are used to understand how visitors interact with the website. 200 Pair Tele DP Box Rs 1,050 / Number Get Latest Price Minimum Order Quantity: 1 Number This product is manufactured by using top grade raw material and ultra-modern technology according to the defined quality standards under the constant supervision of our professionals. Telco wire colors for 25-pair cables Colors used in telco wires. Notice that the blue pair is in the center. stripes and those without them, but the basic color codes are the same. The blue pair is; first, the orange pair is second, the green pair is third, and the brown pair is fourth. The color blue indicates the cable that is headed towards the Central Office. NOTE: Some text links below go to applicable products on eBay or Amazon. The new telephone jacks have red, green, yellow, and black terminals, but the wires inside my walls have eight wires with different color stripes. 9 ft. Deluxe HDMI Cable (2-Pack) Add to Cart. For example, a 900-pair cable has the first 600 pairs in 24 groups of 25 pairs in a white binder, and the remaining 300 pairs in 12 groups of 25 pairs wrapped in a red binder. #1 Cond. The gel-filled insulation of PIC cables naturally prevents moisture from entering the cable. Bd and J-2Y(St)Y . Limited Access Locations - A limited access location is a site where pickup or delivery is restricted or limited. When removing the old telephone jacks, take note of the telephone wire color code and which wires are being used on the old jacks. or MMJ). How does this relate to the residence? BT external overheadcable contains 3 red, or 3 yellow wires. This video explains all about how the Telephone Color Code work, and how to locate any pair within a 25 pair cable.WHAT IS 5G INTERNET: https://youtu.be/4gSRntOSBiM FTTN VS FTTC VS FTTH: https://youtu.be/rncd_GPBaDwPREVENT DSL FAILURE: https://youtu.be/i1tXOCrhtVsBITS VS BYTES: https://youtu.be/gb5ufTwGx58IP ADDRESS SUBNETTING: https://youtu.be/X7v4dyoS0hAFREQUENCY VS BANDWIDTH VS SPEED: https://youtu.be/Zr6JhdqbppsHOW IP ADDRESSES WORK: https://youtu.be/Fc51kDycRdAHOW CELL PHONES WORK: https://youtu.be/wERhV5o2QDsLINE OF SITE WIRELESS INTERNET: https://youtu.be/eZvF-Bpb6VoHOW CABLE MODEMS WORK: https://youtu.be/85jNyclw9loHOW TO STOP WIFI SLOW-DOWN: https://youtu.be/xh5uzQQXegEHOW CELL PHONE TOWERS WORK PT.2: https://youtu.be/E_Ceg06rzcgHOW CELL PHONE TOWERS WORK PT.1: https://youtu.be/R_IaXwGzLhoHOW ETHERNET CABLES WORK: https://youtu.be/pOCKpQEgXlgSHIELDED VS UNSHIELDED TWISTED PAIR CABLES: https://youtu.be/JZb9OhlDYIwFREQUENCY VS BANDWIDTH \u0026 SPEED: https://youtu.be/qUBhgbIUkdkFASTEST INTERNET ACCESS (FIBER OPTIC CABLE: https://youtu.be/MoYpy7-oKX8WHAT IS A DSL LINE BRIDGE TAP https://youtu.be/JDCc4pkdTLESetup Local Area Network with Cisco Packet Tracer: https://youtu.be/rMBkaaWg-8UTelephone Wire Color Code: https://youtu.be/1bZ9niZvyeAHow T1 Lines Work: https://youtu.be/qYNdVUguiqYHow VDSL2 Vectoring Work: https://youtu.be/ZlmBqfH7u3EHow Modems, Switches, \u0026 Routers, work: https://youtu.be/gwDaSY-1SRsHOW DSL BONDING WORK: https://youtu.be/tYOnFH4JECcHow Touch Tone Phones Work: https://youtu.be/y5C244KrQpEHow DSL Lines Work: https://youtu.be/NsSM0FK-0ckHow Rotary Phones Work: https://youtu.be/cLGd6OB8D5kCAUSES OF WIFI SLOW DOWN: https://youtu.be/bcra9vnT41AHow Twisted Pair Work: https://youtu.be/NN1mktbqZAo Wire ID is essential for safety and efficiency, and adhering to wire color codes is an integral aspect. configurations. PIC cables were also gel-filled. The yellow and black wires were usually used to power the lighted dial. Orders received during non-business days are processed on the next business day. var PAGENAME = escape(''); Phase 2 wiring should be orange. They have some similarities to PIC cables except that their tip and ring wires are not twisted together, but separated, all tip wires are bundled together, and all ring wires are bundled together. In a white/blue pair the white conductor would have blue bandmarks (or a blue Older telephone wiring was a basic Cat-3, 4 conductor or 2-pairs with red, green, black, yellow. One extra pair (red-white) may be embedded into cables that are 6 to 75 pairs; two pairs (red-white and black-white) may be encapsulated in cables of 100 to 300 pairs; and three pairs (red-white, black-white, and yellow-white) may be included in cables of 400 to 900 pairs. Bd, J-HH . A small lead cable in a manhole that has been cut off. On this Wikipedia the language links are at the top of the page across from the article title. Lead cables do not have any printing on the outside of the cable. of Units: 1x200 P at Rs 1100/meter in Delhi, Delhi. Note 2: Uppercase letters indicate the base, solid colour of insulation, and the lower case indicates ink bands applied onto the base colour. a-core of 1st pair in each layer is red, all other pairs are white. Note: Plugs/jacks and punchdowns have different . T-screen cables have an aluminum wrap inside the poly jacket which is usually very noticeable on the cables inside of pedestals. An advertisement of the new PIC cable in 1960. A lead aerial cable with a pre-molded splice case. Black white yellow blue color code 50 100 200 300 pair telephone cable $0.05-$0.50 / meter 610 meters (Min. 3) Optionally select a position to save count to. 10/100 base T Ethernet uses the green and orange pairs, specifically so that you can still use the blue and brown pairs for telephones. jack. In 1958 came the PIC cable, Polyethylene Insulated Cable. 5 for Paired Cables (Western Electric Standard) The keyed Paper cables have a paper mulch insulation of the tip and ring wires, an outer polymer (plastic) jacket, and just like lead cables they were air core, meaning they had no filled interior. A second telephone line with a different phone number would terminate on solid Black andsolid Green. PIC cables have a steel/aluminum sheath around the conductors, and a polyethylene outer jacket. bandmarks or stripes to the tip conductor (all the ring conductors will be a 625 codes won't be able to tell this many wires apart! This system has been used quite often, mainly by telcos that were part of the Bell System, but it is not a guarantee of direction. For standard phone service, you can plug a standard two-pair phone plug into this jack. Unshielded telephone cable (UTC), category 2, solid xx - 10pair, 25pair, 50pair, 100pair . Use the two wires in one of those pairs for your telephone connection. All Photos and Text Published on MrElectrician.TV is Copyrighted Material. Bringing edge computing capabilities into your local automation infrastructure with an industrial-grade device capable of running applications that make operational data more useful. . referred to as RJ11, which may or may not be correct. All rights reserved. Group 1, Super-units Binder Identification Colours. Paper cables were the first to use the 4-letter code, and on phone prints they are shown with the 4-letter code, and usually with the letter D in the second position, such as HDBF or ADKA. The PIC cable has an aluminum/steel sheath inside the poly jacket. Note: Alternative make-ups are shown for some sizes and as a further alternative any cable can be made-up using 25 Pair Units throughout. each group of 25 pairs is wrapped in a Binder that is colored according to the table colored electrical wire, electrical color code, electrical wire color coding chart, red green white black brown blue wires meaning, AC Wire Colors, price ft . var TRANSACTION = escape(''); Gophers can easily chew through a PIC cable. At various points the air hose will connect into the cable. #2 External overhead telephone line colour code: orange / white = line 1; green / black = line 2. Major and minor colors are chosen from two different groups of five, resulting in 25 color combinations. . All of the air cables must connect to a dryer/compressor somewhere along the line. cable telephone pair 200 callosum corpus Multi Pair Telephone Cable,Outdoor Connecting Telephone Wire,Underground Telephone Cable Color www.alibaba.com cable telephone network code connecting pair multi outdoor underground wire connection accessories Necessary cookies are absolutely essential for the website to function properly. Anixter.com orders do not currently ship to addresses outside the United States or military/government APO/FPO locations. Topics Covered in this Guide. The binder color sequence is the same as that of the The 25 pair would become the smallest cable. In addition to the 4-Letter code, there may sometimes be another 2-Letter code shown after the pair count, such as: BKTA 200 BT. Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. Below is a diagram for four pair wire on a plug and jack. PIC cables are indicated on phone prints with the 4-letter code, such as ANMW. There are indicators on the mylar ribbons to know where to begin for each layer and a diagram for the different cable sizes should be readily available for reference.[5][6]. The wire pairs are referred to either directly by their color combination, or by the pair number. 100, 200, 300 and 400-pair 110-type panel for interconnection wiring . Order) is for cutting coaxial cable and more. For new sockets, spare parts and the correct inserter tool click here Sockets and Parts. 1091. These are the standard color codings for telephone cables containing up to 26 pairs. PIC Polyethylene Insulated Cables have been the only phone cable since 1958. CAT5 cable has four separate twisted pairs. other. // hitlens v1.2.7 The most common is the RJ-11, which uses only two of the wires in a four (or more) conductor small cable. Dont strip the insulation from the wires when terminating the telephone cable. The insulation material within the cable was a mulched paper (pulp) which insulates every tip and ring wire, the outer sheath/ jacket is lead including the splices. modified modular plug (MMP) to eliminate the possibility of connecting DEC data MULTI CONDUCTOR CABLE MULTI-PAIR COLOR CODES. The original coding system for telephone cables was used on phone prints but not on the cables themselves. This is of course not a lot of pressure, but enough to do the job. The low voltage wiring to the princess telephone power transformer was ordinary cat 3, two-pair telephone wire. The other is the RJ-14, which uses four wires and its used to handle two telephone lines or 2-line phones. The first colour is chosen from one group of five colours. Unit Binder Color code is used to separate multiple Binder bundles. 277/480. 4) Click the "Color Code" button. that here. The air hose will come from the compressor into the manhole, where it will make its first connection onto the cable. Kolors telephone cables 90m; Finolex 0.5mm 10 pair jelly filled telephone cables, 90m Internal Cable Colour Code. Find phone cable at Lowe's today. The table below shows how they relate to each Terminal 3 isreserved for the Bell Circuitto link extension sockets to the Master Socket. BEWARE when cutting or stripping this cable the wiresare EXTREMELY sharp and will leave a nasty prick or cut. If you are installing a new jack, it's best to use As an Amazon Associate, I earn from qualifying purchases. So for one phone line, the blue pair should be the correct line to connect to. Counting direction in all units is from inside to outside. This category only includes cookies that ensures basic functionalities and security features of the website. CAT5 connectors (RJ45) have 8 contacts (4 wire pairs); standard telephone jacks (RJ11) have 4 contacts (2 wire pairs). 3. The original purpose of that transformer was to provide power to a Princess Telephone with a dial that lit up. It is desirable for manufacturing purposes to combine four 25-pair groups into "super units" when cables have 900-pair or more. This applies to Underground fed properties with older BT cable, and BT overhead 'Dropwire'. Featured Keywords. requirements dictate more frequent twists per foot and the conductors of a pair would be a solid white Tip wire, and a White/Blue Ring wire twisted together The primary color of the conductor is the first color listed, the second color is the tracer. One color code used for fiber-optic cables, TIA-598-C, starts with the same first ten colors, adding rose for 11 and aqua for 12.[8]. T1 T-Screen T-Screen cables are used in the T-1 through T-3 systems. For cables containing more than 26 pairs, a Binder Color Code wraps multiple bundles of 25 While not necessary to use in the app. Some common features to consider are Jacket Color and Connector Type. Do not underestimate the danger of the steel support wires. The major, or primary group of colors consists of the sequence of white, red, black, yellow, and violet. The change in this practise though came along with Broadband as the ADSL filter now has the component to enable each phone to ring. dia. All cores in each unit are marked with coloured rings and ring-groups. The 20-pair colour code is a colour code used in Australia to identify individual conductors in a kind of electrical telecommunication wiring for indoor use, known as twisted pair cables. One pair of wires is used for one telephone line. Bd. Bd. It gives color codes for cables with . These might be called C codes because each of them consists of a number, or numbers, followed by the letter C, but actually the C simply means code. The paper insulation remained, so the name paper cable is often used to identify them. 2023, I want to replace all the old telephone jacks, but I am confused by the tip and ring color code. group becomes the basic building block for bigger cables. If you wish to ship to an address outside the United States or a military/government location, please contact your local Anixter sales representative to discuss your options. Their tip and ring wires all have individual color coded plastic insulation within a specific bundle, so all 25 pairs in a bundle have individual color codes, then each bundle tape has a different color code. For products that will be shipped via LTL, you will be provided with a set of Accessorials to select from to provide Anixter with additional shipping considerations, such as residential delivery, inside delivery, liftgate or limited access. The 24th binder group has a violet/brown ribbon, completing a super binder of 600 pairs. A 26 pair cable with 26 gauge wire would be listed as 26-26. The two conductors of a pair of Sheathed Catenery Sheathed Cable Approx Part No. CABLE CONSTRUCTION Telephone Cable is Manufactured in standard sizes ie 1 pair, 2 pair, 3 pair, 4 pair ,6 pair, 10 pair, 15 pair, 20 pair ,30 pair, 50 pair, 100 pair A Standard colour code is used to identify each pair. The in-wall rated cable jacket allows for code compliant wall-mount flat panel installs. They may show only the 4-letter code, sometimes with just an additional B for the buried cables, while more simplified prints may only show the C codes, probably with F/O for the fiber lines. For example, pair 9 is also called the red-brown pair. When using Cat5 use the center pair (Blue/Blue-white) in the CAT5 cable. In technical tabulations, the colors are often suitably abbreviated. #1 Cond. Orange-White,Red-Slate,Blue-Brown,Yellow-Violet,Green-Black,Red-Grey,Blue-Brown There is also a variation on this colour code for earlier cable of this type. Dia. 2-paired cables: the cores are stranded to a star quad: circuit 1: a-core blue b-core red circuit 2: a-core grey b-core yellow Each unit is assigned to one group of ring. Pair one, for example, has one white conductor With the development of new generations of telecommunication cables with polyethylene-insulated conductors (PIC) by Bell Laboratories for the Bell System in the 1950s, new methods were developed to mark each individual conductor in cables.