Chapter 6 Troubleshooting
T1/E1 CSU loop up & loop down codes
TC8518 Rev 2.2 User Manual
6-9
Figure 6-11 T1/E1 Remote Loop Back Signal Flow
TC8518 Unit A
Loop Monitor
TC8518 Unit B
Loop Monitor
Functionality
Disabled
Enable Remote
This setting allows the Telco to send loop codes
that will enable/disable the remote loopback on
Unit B for a specific T1 channel.
Figure 6-12 T1/E1 Local Loop Back Signal Flow
TC8518 Unit A
Loop Monitor
TC8518 Unit B
Loop Monitor
Functionality
Enable Local
Disabled
This setting allows the Telco to send loop codes
that will enable/disable the local loopback on Unit
A for a specific T1 channel.
