Nortel Networks 1000 - Manual (Page 622)

622 NT8D14 Universal Trunk card
Table 235
Trunk types - termination impedance and balance network (NT8D14BA, NT8D14BB) (cont’d.)
Balance network for loop lengths (Note 2)
Trunk types
Terminating
impedance
(Note 1)
0–915 m
(0–3000 ft) 915–1524 m
(3000–5000 ft) > 1524 m
(> 5000 ft)
RAN: continuous
operation mode 600 or 900
ohms 600 or 900 ohms N/A N/A
Paging 600 ohms 600 ohms N/A N/A
Note: The terminating impedance of each trunk unit is software selectable in LD 14 and should
match the nominal impedance of the connecting equipment.
Note: The balance network of each trunk unit is software selectable between resistive 600 or
900 ohms or 3COM and jumper selectable between 3COM and 3CM2. Jumper selection for
3COM/3CM2 restriction does not apply to NT8D14BB (Release 10 and later).
Table 236
Cable loop resistance and loss
Cable loop resistance (ohms)
Cable loop loss (dB)
(nonloaded at 1kHz)
Cable length 22 AWG 24 AWG 26 AWG 22 AWG 24 AWG 26 AWG
915 m (3000 ft) 97 155 251 0.9 1.2 1.5
1524 m (5000 ft) 162 260 417 1.6 2.0 2.5
2225 m (7300 ft) 236 378 609 2.3 3.0 3.7
3566 m (11700 ft) 379 607 977 3.7 4.8 6.0
5639 m (18500 ft) 600 960 1544 5.9 7.6 9.4
Port-to-port loss configuration
Loss parameters are selected on the NT8D14 Universal Trunk card by a
switchable pad controlled by codec emulation software. For convenience,
the pads settings are called "in" and "out." Pad settings are determined
by the two factors listed below (the first is under direct user control; the
second is controlled indirectly):
• Class of Service is assigned in LD 14 (under direct user control).
•
Port-to-port connection loss is automatically set by software on the
basis of the port type selected in LD 16; only the port type is set by the
user (controlled indirectly).
The transmission properties of each trunk are characterized by the class of
service assigned in LD 14. Transmission properties can be Via Net Loss
(VNL) or non-Via Net Loss (non-VNL).
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 02.06 Standard
27 August 2008
Copyright © 2003-2008 Nortel Networks
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