100 pairs telephone cable

The communication cable sequence is a standardized color chromatic arrangement system for identifying pairs of conductors in urban communication cables. It is mainly used for telephone cables such as HYA and HYAT. It uses a cyclic combination of five primary colors (white, red, black, yellow, and purple) and five secondary colors (blue, orange, green, brown, and gray) to form 25 basic units. For example, a 10-pair cable uses the first two sets of primary colors [1-2]. The sequence realizes the "mutual check of line numbers and line pairs" identification mechanism through the bidirectional correspondence of primary and secondary colors [1]. Large-pair cables are superimposed and expanded with 25 pairs as the basic unit, and are distinguished by color classification using identification lines or cable ties. For example, a 30-pair cable is grouped using "white-blue" and "white-orange" identification lines, a 100-pair cable is divided into four groups using four-color identification lines, and cables of 200 pairs or more are identified by eight groups using different colored cable ties [1-2]. The system complies with the YD/T322-1996 specification and covers cable structures such as HYA22 armored and HYAT filled cables. It is suitable for metropolitan area network overhead, pipeline, and direct burial installation scenarios [2]. The armored communication cable also meets the standards such as GB/T 9330-2008, is equipped with 1% spare wire pairs, and uses tinned copper wire conductor technology. Flame-retardant cables such as ZR-DJYPV use a separate shielding structure, while mining cables are adapted to the 568B wire sequence standard.