Verilink SCC 2130 (880-503282-001) Product Manual - Manual (Page 64)

Diagnostics
5-10 Verilink SCC 2130 User Manual
Results If the test passes, consider doing the same test with a different
pattern. Some patterns will fail on a T1 which passes other test
patterns. See
Table 5-2 for details on the various patterns.
Test Failures If the test fails consider one of these alternatives:
• Use a loopback closer to the local CSU. The telephone carrier
may be able to put up loopbacks at various locations along the
path of the T1 circuit. Start far away and work your way back
to the local CSU.
• If it appears that the local CSU is defective try using a Repeater
loopback. Send a test pattern while the local CSU is in Repeater
loopback, the test pattern never leaves the CSU because it is
receiving what it is sending. If this test passes the CSU is
probably OK.
• If a problem is identified but not resolved by this procedure,
go on to the next section, “Troubleshooting”.
Troubleshooting When it is known that a problem exists in a T1 network application,
a different approach is suggested. In the verification procedure
above the initial test passed data through the entire T1 circuit,
including both local and far end CSUs. This was done because of
the expectation that no trouble would be found.
With trouble known to exist, begin by establishing what is good.
Start with a repeater loopback test in the local CSU.