User Guide

ISDN Interfaces
RBUU/RBUS Interface Unit
Strata CTX I&M 06/04 7-31
ISDN Interfaces
• The ISDN BRI-U wire pair is usually on the center pair of the Demarc jack, pins 3 and 4 on
RJ11 and pins 4 and 5 on RJ45. Demarc coding is shown in Tables 7-13, 7-14 and 7-15. Typical
demarc jack wiring is shown in Figures 7-27 and 7-28:
Figure 7-27 Six-pin Modular Plug (RJ11)
Figure 7-28 Eight-pin Modular Plug (RJ45)
Table 7-13 Quad Cable with RJ11 Demarc Coding
Conductor Color Pin Use
Pair 1
Red 3 Line 1
Green 4 Line 1
Pair 2
Yellow 5 Line 2/Power
Black 2 Line 2/Power
RJ11 Demarc Jack
4726
6
5
4
3
2
1
BLACK
RED
GREEN
YELLOW
RJ45 Demarc Jack
4727
1
2
3
4
5
6
7
8
WHITE-GREEN
GREEN
WHITE-ORANGE
BLUE
WHITE-BLUE
ORANGE
WHITE-BROWN
BROWN