Nortel Networks Circuit Card User Manual
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NT5D33 and NT5D34 Lineside E1 Interface cards
553-3001-211 Standard 3.00 August 2005
CPE at the far-end will likewise have transmit and receive wired straight from
the RJ48 demarc at the far-end of the carrier facility.
For 75 ohm coaxial installations, E1 signaling for all 30 channels is
transmitted over P2 connector pins 1, 3, 9, and 11 though an adapter and out
two coaxial connectors Tx (transmit) and Rx (receive). Tx is the LEI output,
and Rx is the LEI input from the E1 stream. E1 transmit and receive pairs
must be turned over between the LEI and the CPE that is hardwired without
carrier facilities. If the LEI is connected through E1 carrier facilities, the
transmit and receive pairs must be wired straight through to the RJ48 at the
Telco demarc, the LTU, or other E1 carrier equipment. The E1 CPE at the far
end will likewise have Tx and Rx wired straight from the RJ48 demarc at the
far end of the carrier facility.
External Alarm Connections
P3 connector pins 1, 2 and 3 can be plugged into any external alarm-sensing
hardware. Plug the DB9 male connector labeled “P3” into an external alarm.
These connections are optional, and the LEI functionality is not affected if
they are not made.
The MMI monitors the E1 link for specified performance criteria and reports
on problems detected. One of the ways it can report information is through
this external alarm connection. If connected, the LEI’s microprocessor will
activate the external alarm hardware if it detects certain E1 link problems it
has classified as alarm levels 1 or 2. See “Man-Machine E1 maintenance
interface software” on
for a detailed description of alarm levels and
configuration. If an alarm level 1 or 2 is detected by the MMI, the LEI will
close the contact that is normally open, and will open the contact that is
normally closed. The MMI command “Clear Alarm” will return the alarm
contacts to their normal state.
MMI Connections
P5 connector pins 2, 3, 5, 7 and 9 are used to connect the LEI to the MMI
terminal, connecting LEIs in a daisy chain for access to a shared MMI
terminal. When logging into a LEI, “control 2” is asserted by that card, which
informs all of the other cards not to talk on the bus, but rather to pass the data
straight through. The pins labeled “control 1” are reserved for future use. As
with the external alarm connections, MMI connections are optional. Up to