In the Telephone binder groups there is no binder group corresponding to the 25th group Violet/Slate This group was omitted intentionally to facilitate ease of counting in 600 pair groups.
By using these simple 10 colors a combination of 25 unique pairs can be realized. Where Each Tip Color is combined with each Ring Color. Each time the 25th pair is reached that group of 25 is wrapped with a plastic binder that follows the same color coding sequence as the pairs of wires until it reaches 600 pairs total. Then that group will be wrapped with a super binder color that follows the Tip Color sequence only. White, Red, Black, Yellow, Violet.
Mnemonics: Bell Operators Give Better Service
Blue Orange Green Brown Slate
Why Run Backwards Young Virgins
White Red Black Yellow Violet
Fiber Optic cables utilize the same primary 10 colors for the first 10 fibers but then add two additional colors Rose and Aqua.
Unlike Telephone cables fiber color coding has only a single color on each tube for the first 12 fibers. The second 12 are marked with an additional Black tracer line on each fiber except for the Black fiber #20 which has a yellow tracer for visibility.
General Cable Manufacturing made a variation of the 600 pr. Super binder for cables larger than 2400 Pr. The 300 Pr. Super Binder They also included spare pairs in the event some were bad.
Horizontal Cabling balanced twisted pair is by far the most commonly ran cable at present time. While this page offers a brief description of how they are numbered there is not enough space to cover the topic in depth here.
Some information to consider is the speed of the connection - this varies by cable type CAT3, CAT5, CAT5e, CAT6, CAT6a, CAT7, CAT8 each has their own limits on speed determined by not only conductor gauge, and conductor length, amount of twists, and also the type of conductor (solid or stranded) used as a patch cable to connect to the horizontal cable.
NOTE: (Stranded conductor is never used as the horizontal portion of the circuit).
Typically the horizontal cannot run more than 100 meters total, with the limit on the horizontal cabling at 295', and the patch cables 16'.
Some articles to read on this subject would include:
Ethernet Cabling, Structured Cabling, Balanced Twisted Pair, VOIP (Voice over Internet Protocol), Video Conferencing, Data Communications, just to name a few.
BICSI - Building Industry Consulting Service International
Offers publications which provide a wealth of information to not only the new
apprentice technicians entering the field, but also to the seasoned professional, by constantly updating practices and methodology as it evolves BICSI standards help to insure your installation will your clients communications objectives.
Contractors are required to mark the pavement where they intend to dig or bore prior to the utility companies marking the existing facilities . Typically the utilities have two days to get their facility marked.
PINK - Temporary Survey Markers
Electric power lines and cables, conduit and street lighting cables
Gas. Oil, Steam, petroleum or gaseous materials.
Communications Cables or Fiber, alarm or signal cables or conduits
Water fit for human consumption
Purple - Reclaimed Water