Verilink SCC 2130 (880-503282-001) Product Manual User Manual
Page 68
Diagnostics
5-14
Verilink SCC 2130 User Manual
With a loopback plug in the network port, any customer equipment
connected to the SCC 2130 should see a loopback condition. If the
customer equipment is capable of reporting errors, it should
indicate that no errors are being received.
A T1 loopback plug can be made by taking a male RJ-45 connector
and placing two short jumper wires where a cable would normally
go. One jumper is placed from pin one to pin five, the other jumper
connects pin two to pin four. See
for
a drawing of a T1
loopback plug.
NOTE: When using a T1 loopback plug it may be necessary to
temporarily change the timing selection in the IDCSU. If the
IDCSU is set to recover network clock it will be trying to
recover a clock it is trying to recover, the clock frequency will
drift. For this test, set the IDCSU clock source to Internal.
Figure 5-5
T1 Loopback Plug
RJ -45
8
Cable Side
Connector
2
4
5
1
RJ-45 plug held with plastic latching tab unseen at bottom