A-2
A
PPENDIX
A: T
ROUBLE
C
LEARING
*If Layer 1 alarms exist, Layer 2 status is not indicated.
If LEDs indicate an alarm condition, refer to the alarm event status screen
for details.
Alarm LEDs will still register during loopback.
About T1/PRI Alarm
Levels
Layer 1 alarm conditions are categorized into one of three alarm levels:
CD (1 or 2)
LED Color
ALRM (1 or 2)
LED Color
LPBK (1 or 2)
LED Color
T1 Condition
Green Off Off No Alarm
Green Red Off Remote Frame Alarm
(RFA)
Off Red Off Loss of Signal Alarm
(LOS)
Red Red Off Out of Frame Alarm
(OOF)
Red Red Off Unframed All Ones Alarm
(AIS)
Green Off Green Loopback in Progress
Layer 2 (D-channel Status)*
Any Any Off Signaling Channel Up
Any Any Amber Signaling Channel Down
Alarm Severity Result
Red Alarm High Loss of connection and/or data locally
Blue Alarm High No data received from Telco; all 1’s received by NAC
Yellow Alarm High Improper data received at remote end
