Physical Description - Nortel Circuit Card Installation Manual

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Physical description

External D-Channel Interface DCH or MSDL
553-3001-211 Standard 3.00
NT5D97 Dual-port DTI2/PRI2 card
The NT5D97 DDP2 card hardware design uses a B57 ASIC E1/T1 framer.
The carrier specifications comply with the ANSI TI.403 specification. The
NT5D97 provides an interface to the 2.048 Mbps external digital line either
directly or through an office repeater, Network Channel Terminating
Equipment (NCTE), or Line Terminating Unit (LTU).
DANGER OF ELECTRIC SHOCK
The NT5D97 DDP2 card is not designed to be
connected directly to the Public Switched Network, or
other exposed plant networks. Such a connection
should only be done using an isolating-type
networking terminating device that provides voltage
surge protection, such as a Line Terminating Unit
(LTU), Network Channel Terminating Equipment
(NCTE), or Network Termination 1 (NT1), as certified
by your local, regional, or national safety agency and
telecommunication authority.
The connection between the DDP2 card and the external DCH or MSDL is
through a 26-pin female D type connector. The data signals conform to the
electrical characteristics of the EIA standard RS-422.
Two control signals are used to communicate the D-channel link status to the
DCH or MSDL. These are:
• Receiver Ready (RR), originating at the DDP2 card, to indicate to the
DCH or MSDL that the D-channel link is operational.
• Transmitter Ready (TR), originating at the DCH or MSDL, to indicate to
the DDP2 card that the DCH are ready to use the D-channel link.
August 2005