Toshiba DK14 Installation And Maintenance Manual page 344

T1
Flowchart Symbols
Flowchart 8-3
Slip problems cause
periodic clicking on the
talk path. Clicks can occur
many times (severe case)
during a call or only a few
times during a 24-hour
period.
Slips occur when
synchronization timing is
lost for an instant and then
recovers.
Monitor slips using
"T1ERR" function in
DK280 remote
maintenance DUMP
mode.
One example of a slip fault
when using more than one
RDTU T1 span is provided
in Figure 8-6.
Use Program
*
If problem continues try another RDTU as Primary reference.
Change the RDTU that was
causing slip problems when it
was set-up as Primary reference.
1681
8-22
Synchronization Slip Problems
• If RDTU spans are connected to a Telco
or...
long distance provider, program the rst
RDTU as the primary reference and the
second as a secondary reference using
Program 42 (see Figure 6-7).
*
• If a third RDTU is connected to a PBX,
the PBX should be set up as a slave to
the RDTU.
• If all RDTUs are connected to a PBX,
then either the RDTUs can be set as
primary and secondary references
(slaves) and the PBX as the master
(Program * 42 data is blank; or, all
RDTUs should be set as the master and
the PBX T1s should be slaves.
Program as required.
42 and assign a different RDTU as Primary reference.
Yes
Start
Is
there more
No
than one RDTU
installed
?
Yes
2
Is slip
problem cleared
?
No
Is slip
problem cleared
?
No
Go to
3
Contact your
No
technical support
group.
1
• If RDTU is connected to a reliable
clock source (Telco, AT&T etc.)
then it should be programmed as a
slave (primary reference) to the
provider. (Program * 42 – data = 1).
• If RDTU is connected to a PBX or
channel bank, make sure that
RDTU is programmed as the
master clock provider (Program * 42
– data = blank); or, if the PBX is set
up as a master, the RDTU should
be programmed as a primary
reference.
Program as required.
Yes
Is slip
problem cleared
?
No
3
• Check all cable connections and
correct as necessary.
• Change CSU.
• Change Primary reference RDTU.
• If problem continues after RDTU is
changed, change RCTU.
• If problem continues after CSU, RDTU,
and RCTU are changed, contact the T1
provider and request a point-to-point
slip test from NIU to far end T1.
Yes
Is slip
problem cleared
?
Strata DK I&M
End
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