Subelement L: L – Installation, Maintenance & Repair— Topic 80: Installation Codes & Procedures
Question 3-80L4
Element 3 (GROL)What is the 6th pair color code in a 25 pair switchboard cable as is found in building telecommunications interconnections?
Explanation
The 25-pair color code is a standard for identifying individual wire pairs within telecommunications cables, often used in building interconnections. This system uses a combination of five "tip" colors (White, Red, Black, Yellow, Violet) and five "ring" colors (Blue, Orange, Green, Brown, Slate).
The pairs are numbered sequentially:
The first five pairs use White as the tip color with each of the five ring colors (White/Blue, White/Orange, White/Green, White/Brown, White/Slate).
The next five pairs (pairs 6 through 10) use Red as the tip color.
Therefore, the 6th pair combines the second tip color (Red) with the first ring color (Blue). The pair consists of two conductors: one primarily Red with a Blue stripe, and the other primarily Blue with a Red stripe.
Thus, "Red/Blue, Blue/Red" accurately represents the colors of the two wires in the 6th pair.
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