Nortel 1000 Installation And Commissioning Manual page 268

268 2.0 Mb PRI implementation
For the U.K., use DPNSS1 mode. For all other countries, use Q.931 mode.
Table 98
Switch SW1
Switch
SW 1-1
SW 1-2
Switch SW2 - Carrier impedance configuration
This switch sets the carrier impedance to either 120
cable is usually associated with 120
with the 75
Table 99
Switch SW2
Cable type
75
120
Switch SW4 - Carrier shield grounding
This switch supports the selective grounding of Tx and Rx pairs of carrier
cable. Closing the switch (down position) applies Frame Ground (FGND) to
the coaxial carrier cable shield, creating a 75
This applies only to the NTBK05CA cable.
Table 100
Switch SW3
Switch
SW 4-1
SW 4-2
Mount the daughterboards on the NTBK50
Use the following procedure to mount and remove the NTAK20 CC and the
NTBK51 DDCH or NTAK93 DCHI daughterboards onto the NTBK50 PRI.
Install the NTAK93 or NTBK51 daughterboard before the NTAK20
daughterboard. Work on a flat surface when mounting or removing
daughterboards.
Copyright © 2003-2007, Nortel Networks
.
1 / setting.
2
3 /
4
3 /
4
Note: The usual method is to ground the outer conductor of the receive
coax signal.
Nortel Communication Server 1000
ISDN Primary Rate Interface Installation and Commissioning
NN43001-301 02.03 Standard
Release 5.5 7 December 2007
Down (On)
—
DPNSS1/DASS2
1 / . Coaxial cable is usually associated
2
SW 2-1
Down (On)
Up (Off)
Down (On)
Rx—FGND
Tx—FGND
Up (Off)
—
Q.931
1 / or 75 1 / . Twisted pair
2 2
1 / unbalanced configuration.
2
Up (Off)
Rx—OPEN
Tx—OPEN