21/1531-ASP11301 Uen B3 2016-02-17
40
C
ONNECTION
OF
E
XTERNAL
C
ABLES
Figure 31: 2-wire ISDN with TLU79 and an NT1-box (8 pairs)
Note:
Make sure that each individual’s receive (Rx) and transmit (Tx) are properly
connected between the TLU79 board and the NT1-box. Necessary corrections
between the individuals can preferably be performed in the MDF.
4.7.2.3
Digital external line with TLU79 as a tie line
Color coding for TLU79 with cable TSR491414/xxx see item 3.5.4 ELU26 and TLU79
cable structure on page 34
Figure 32: Connecting TLU79 to TLU79 through MDF (8 pairs)
4.8
THROUGH-CONNECTION ON POWER FAILURE OR
PROCESSOR MALFUNCTION
If the exchange is equipped with an FTU2 board, one to 32 extensions (8 per FTU2
boards) can be through-connected to the public network in the event of power failure
or processor malfunction.