S/T Interface Logic; Physical Description; Power Consumption; Foreign And Surge Voltage Protections - Meridian Nortel 1 Option 11C Technical Reference Manual

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S/T interface logic

Physical description

Power consumption

Foreign and surge voltage protections

553-3011-100 Standard 14.00
NT6D70 SILC line card
The S/T interface logic consists of a transceiver circuit and the DSL power
source. This interface supports DSLs of different distances and different
number and types of terminals.
The transceiver circuits provide four-wire full duplex S/T bus interface. This
bus supports multiple physical terminations on one DSL where each physical
termination supports multiple logical B-channel and D-channel ISDN BRI
terminals. Idle circuit-switched B-channels can be allocated for voice or data
transmission to terminals making calls on a DSL. When those terminals
become idle, the channels are automatically made available to other terminals
making calls on the same DSL.
The power on the DSL comes from the SILC, which accepts -48 V from the
IPE backplane and provides 2 watts of power to physical terminations on each
DSL. It provides -48 V for ANSI compliant ISDN BRI terminals and -40 V
for CCITT (such as ETSI NET-3, INS NET-64) compliant terminals. The
total power used by the terminals on each DSL must not exceed 2 watts.
The NT6D70 SILC is a standard size circuit card designed to be inserted in
peripheral equipment slots in the Meridian 1. Its faceplate is equipped with an
LED to indicate its status.
Power consumption is +5V at 800 mA and -48V at 480 mA.
In-circuit protection against power line crosses or lightning is not provided on
the SILC card. When the SILC card is used in TIE trunk applications in which
the cabling is exposed to outside plant conditions, an NT1 module certified
for such applications must be used. Check local regulations before providing
such service.
January 2002