AT&T System 75 Wiring Diagram page 130

Equipment Room Hardware And Cabling Installation
Label Code 223A—White Labels (comcode 103 970 034)
Label code 223A contains the following labels:
(60) white labels that identify 3-pair circuits from the equipment
room to the satellite closet (Figure 3-31). Each label identifies 16
three-pair station circuits. There are labels for satellite closets
numbered A through F, and each satellite closet has station
circuits numbered 1 through 160.
(20) unnumbered white labels (Figure 3-31) that identify 3-pair
station circuits from the satellite closet. Each label identifies
twelve 3-pair station circuits.
3-PAIR BLUE STATION LABELS
The labels shown in Figure 3-32 identify 3-pair blue station appearances
at the cross-connect field. The top labels are numbered and should be
installed in sequence (1 to 560) starting with the first terminal block in
the blue field. The bottom label must be filled in manually.
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