Avaya S8700 Maintenance Manual page 347

SYNC (Port-Network Synchronization)
Facility Fault Sectionalization
DS1 facility fault sectionalization involves looping around the DS1 signal at on-site
access points to localize the source of the problem to equipment and wiring on
either the near side or far side of the loop-around point.
!
WARNING:
The facility fault sectionalization technique disrupts service. When you
perform the loop around on a facility, make sure it is not the on-line
synchronization reference or a system outage will occur.
When you use this technique to investigate problems on facilities with multiplex or
DACS equipment, the technique becomes cumbersome because every 64-kbps
(B channel) or subrate channel corresponding to the DS1 facility needs to be
looped around.
Figure 8-45
on-site equipment. A typical example is the case where the only on-site
equipment is channel-terminating equipment designated Unit #1. A more
complex, less typical example might have a DACS as Unit #1, a protection switch
as Unit #2, and a DS1-level microwave radio system as Unit #3.
The flowchart in
sectionalization technique. It is important that you know the configuration and
wiring of the equipment for the problem facility in order to support this technique.
Switch
TN767, or
DS1 interface
Figure 8-45. Manual Loop-Around for Facility Fault Sectionalization
Since the technique is time consuming, fix any DS1-BD, UDS1-BD, or SYNC
errors first that are not slip errors.
555-233-142
shows a sequence of units (1 though n) that may be connected as the
Figure 8-46 on page 8-1044
Manually
wired
loop-around
TN722,
TN464
Pairs open
at next unit
gives an overview of the facility fault
Next unit
Next unit
(#N)
(#1)
Span
line
side
sync4 LJK 072501
Issue 1 May 2002 8-1043