3Com NBX 100 Installation Manual page 37

The T1 Digital Line Card has these lights and connectors:
3C10116C
T1 — This RJ-48C connector makes a patch cord connection to a T1
interface (CSU/DSU).
Status Lights — These lights indicate the status of the card's
signaling, synchronization, and loop back test.
CF — On indicates a Carrier Failure. The T1 card is not receiving
carrier signals from the far end of the T1 line.
RA — On indicates a Remote Alarm. The far (remote) end of the T1
line is not receiving appropriate signaling from the T1 board.
LB — On indicates that loop-back testing is in progress.
Nominal — On indicates ready to send and receive information.
10BASE-T Uplink — This RJ-45 Ethernet connector connects the T1
card to an external LAN hub or switch. You can use this connector to
isolate T1 traffic. If the T1 Digital Line Card is used in a V5000
Gateway Chassis, do not use this connector because the chassis has
an Ethernet connector to connect the chassis to the LAN.
If you use the Uplink connector, be sure to program the switch or router
on the other end for 10BASE-T 10 MB operation.
Console — This DB-9 connector provides an RS-232 (DCE) TTY
terminal connection for maintenance access.
The 3C10116D T1 Digital Line Card has the following lights and
connectors:
T1 — This RJ-48C connector makes a patch cord connection to a T1
interface.
Status Lights — These lights indicate the status of the T1 card's
signaling, synchronization, and loop back test.
CO — Central Office:
Amber — Alarm condition at the remote end or the CO is not
connected or available.
Green — No alarm condition.
POST — Power On Self Test
Off — POST test is running. The test runs approximately 5 seconds
after you apply power to the board. After 5 seconds, Off indicates
the POST test failed.
NBX Cards and Devices 37