Programming instructions

APPENDIX F - T1 MAINTENANCE
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Yellow Alarms
• The network sends a yellow alarm to the T1 framer for detection.
• This alarm indicates that the network has detected a transmit signal from the T1
board but cannot synchronize to the transmit frame.
• If a yellow alarm is in effect for more than 2.5 seconds, the system activates a red
alarm.
• If the network removes a yellow alarm within the 2.5 seconds, the system will
return to normal. When a yellow alarm occurs, it is a good practice to check the
network wiring.
• The YELLOW indicator on the T1 board also indicates this condition.
Red Alarms
• The T1 card issues a red alarm for the following conditions:
• at startup until the system establishes synchronization with a good link
• whenever a receive signal is not present
• when the system receives a blue alarm from the network
• whenever a yellow alarm, sent from the network, is active for more than 2.5
seconds.
NOTE
When the above conditions terminate, the red alarm will terminate. The
RED indicator on the T1 board also indicates this condition.
T1 ALARM AND ERROR PARAMETERS (continued)