Nortel Networks Circuit Card 311 - Manual (Page 174)

174 NT5D11 and NT5D14 Lineside T1 Interface cards
If one of these alarm conditions is detected, the red LED lights. Yellow
alarm indication is sent to the far-end as long as the near-end remains in a
red alarm condition. Depending on how the Man-Machine Interface (MMI) is
configured, this LED remains lit until the following actions occur:
• If the "Self-Clearing" function has been enabled in the MMI, the LED
clears the alarm when the alarm condition is no longer detected. This is
the factory default.
• If the "Self-Clearing" function hasnot been enabled or it has been
subsequently disabled in the MMI, the LED stays lit until the command
"Clear Alarm" has been typed in the MMI, even though the carrier
automatically returned to service when the alarm condition was no
longer detected.
The YELLOW ALARM LED indicates that the Lineside T1 card has detected
a yellow alarm signal from the terminal equipment side of the T1 link. See
the
"QPC43 Peripheral Signaling card" (page 104) for information on T1 link
maintenance. If the terminal equipment detects a red alarm condition, such
as not receiving a signal or the signal has exceeded bit error thresholds or
frame slip thresholds, it can send a yellow alarm signal to the Lineside T1
card, depending on whether or not the terminal equipment supports this
feature. If a yellow alarm signal is detected, the LED lights.
The MAINT LED indicates if the Lineside T1 card is fully operational
because of certain maintenance commands being issued through the MMI.
See
"QPC43 Peripheral Signaling card" (page 104) for information on T1
link maintenance. If the card detects that tests are being run or that alarms
are disabled through the MMI, the LED lights and remains lit until these
conditions are no longer detected, then it turns off.
The faceplate of the card is twice as wide as the other standard analog
and digital line cards, and occupies two card slots. It comes equipped with
four LED indicators. See
Figure 30 "Lineside T1 card - block diagram"
(page 177) .
The LEDs provide status indications on the operations as described in Table
79 "Lineside T1 card LED operation" (page 174) .
Table 79
Lineside T1 card LED operation
LED OPERATION
STATUS Line card
RED ALARM T1 near end
YELLOW ALARM T1 far end
MAINT Maintenance
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.