Maintenance for CSI systems
555-233-119
96
Issue 5 October 2002
If the outgoing ISDN-PRI test call keeps aborting, please make sure that the
far-end device can handle DCP Mode 0 or DCP Mode 1.
NOTE:
Before attempting to make an ISDN-PRI test call to the public network (that
is, the network is the far-end), make sure that test call service is provisioned
by the network. The user must subscribe to Test Type 108 service and have
the correct far-end test call number administered on the trunk group screen
for the call to be allowed.
Install DS1 CPE Loopback Jack (T1
Only)
Using the DS1 CPE Loopback Jack (apparatus code 700A, comcode
107988867), a technician can test the DS1 span between the system and the
network interface point. The 700A can quickly isolate DS1 problems to either the
customer premises or to the external DS1 span.
The 700A loopback jack is required when DC power appears at the interface to
the ICSU. The loopback jack isolates the ICSU from the DC power and properly
loops the DC span power. The 700A is also used when no smart jack is installed
by the local phone company.
NOTE:
The loopback jack operates with any vintage of TN767E (or later) or TN464F
(or later) DS1 circuit packs. The loopback jack operates with the 120A2 (or
later) Integrated Channel Service Unit (ICSU) only; not the 31xx series of
CSUs, other external CSUs, or earlier ICSUs.