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2NT1 T400 User Manual 61212016L1-1
1.02 Basic Rate Description
ISDN Basic Rate Service consists of two “B” channels at 64 kbps
and a single “D” channel at 16 kbps. Basic Rate Service (2B+D Ser-
vice) provides a total of 144 kbps to the customer for the transport
of voice, circuit switched data, and packet switched data. Each
“B” channel can be used for voice or data. The “D” channel carries
the signaling information needed for call processing. The “D”
channel can also carry packet switched data using the X.25 proto-
col.
1.03 Passive Bus Description
The “S/T’’ interface used to connect to the customer TE has the
ability to connect multiple devices. This arrangement is referred
to as the “passive bus” and can be used to connect up to eight TEs
to the same Basic Rate line, as described in APPENDIX B.
1.04 Powering TEs from the NT1
The ADTRAN NT1 Type 400 can be used to provide power for
customer TEs. If the NT1 T400 circuit pack is used, a total of 12
watts is available. If the NT1 Type 400 Standalone unit is used, a
total of seven watts is available. This power can be provided by
Power Source 1 (PS1), which provides power over the transmit
and receive wire pairs used by the “S/T” interface and requires no
additional wire pairs; and by Power Source 2 (PS2), which pro-
vides power over an additional wire pair.
1.05 Rear Panel
The NT1 Type 400 Standalone rear panel contains three RJ45 con-
nectors, as illustrated in Figure 1. A single connector, labeled
“NETWORK,” is used to connect to the ISDN network. The re-
maining two connectors, labeled “CUSTOMER 1” and “CUS-
TOMER 2,” are used to interface to the customer’s TEs. These
connectors are wired in parallel, and can be used to connect mul-
tiple TEs in a passive bus arrangement.
Figure 1: NT1 Type 400 Standalone Rear Panel
NETWORK
CUSTOMER 1
CUSTOMER 2
115
VAC
60 HZ
.07 A