Toshiba Strata AirLink DK40i, Installation And Maintenance Manual

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ISDN Interfaces
RBUU/RBUS and TBUU Interface Unit
16-34
Strata DK I&M 6/00
Line-side cabling
♦ The ISDN BRI U-interface circuits are two-wire on the PSTN line-side.
♦ The wiring from the demarc to the DK BRI circuit should be made with CAT3~CAT5 twisted
pair wire.
♦ The pinout of the DK BRI-U circuit jack is shown below.
♦
DK BRI-U RJ45 Circuit Jack Printout
♦
The maximum distance between the PSTN BRI interface circuit and the DK ISDN BRI U line-
side circuit (NT) is 18 kft. The Telco with the use of a repeater or fiber optic cable may extend
this distance.
♦ The U interface pair should go directly from the demarc jack to the DK interface PCB with no
bridge taps to different locations or should not have loading coils installed.
♦
BRI line-side cables should not be shielded.
♦
Each line-side BRI circuit requires a ferrite core as shown in Figures 16-15 and 16-16 .
♦
In the USA, most BRI-U Demarc jacks are RJ11, but they may be RJ45 eight-wire jacks. In
Canada the BRI-U Demarc jack is usually RJ45.
♦
Polarity of the U interface pair is not critical.
♦ 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. Typical demarc jack wiring is shown below:)
Figure 16-27 Six-pin Modular Plug (RJ11)
RJ45 Jack
NT and LT Mode
4732
8
7
6
5
4
3
2
1
NC
NC
NC
Tip
Ring
NC
NC
NC
NC = No Connection
BRI Pai
RJ11 Demarc Jack
4726
6
5
4
3
2
1
BLACK
RED
GREEN
YELLOW