DEFINITY ECS Release 8.2 Maintenance for R8.2csi
555-233-119 Issue 1
April 2000
Maintenance for csi systems
1-75Install DS1 CPE Loopback Jack (T1 Only)
1
9. Repeat Steps 5 through 8 as desired to observe bit error rate
characteristics. Also, wait 1 to 10 m inutes between Steps 5 through 7. One
minute without errors translates to better than a 1 in 10 to the eig hth error
rate. Ten minutes without errors translates to better than a 1 in 10 to the
ninth error rate.
10. If the test runs for 1 minute with an error count of 0, c onfirm that the 3-in-24
pattern error detector is op erating properly b y entering test ds1-loop
<location> inject-single-bit-error. This causes the 3-in-24 pattern
generator on the DS1 circuit pac k to inject a single-b it error into the
transmit pattern. A subseq uent list meas ds1 summary <location>
command disp lays the bit error count. If a c ount greater than 1 is
displayed, repl ace the ICSU and retest. If the problem continues, replace
the DS1 circuit pack.
11. Terminate the test by entering test ds1-loop <location> end
cpe-loopback-jack-test. Wait about 30 seconds for the DS1 to re-frame
on the incoming signal and clear DS1 facility alarms.
Loopback terminati on fails under the following c onditions:
a. The span is still looped somewhere. This could be at the loopback
jack, at the ICSU, or somewhere in the network. This state is
indicated b y a fail code of 1313. If the red LED on the loop back
jack is on, replace the ICSU. Re-run the test and ve rify that the
loopback test termina tes properly. If not, replace the DS1 circ uit
pack and repeat the test.
Bit Error Count Cumulative
count of
detected
errors
If there are no wiring problems, the counter
remains at 0.
A count that pegs at 65535 or continues to
increment by several hundred to several
thousand on each list meas command execution
indicates intermittent or corroded connections,
severe crosstalk, or impedance imbalances
between the two conductors of the receive pair or
the transmit pair. Wiring may need replacement.
Note that “ESF error events” counter and the ESF
performance counter summaries (“errored
seconds”, “bursty errored second s”, and so forth)
will also increment. These counters are not used
with the loopback jack tests. However, they will
increment if errors are occurring. Counters should
be cleared following the test.
Tabl e 1 -7 . DS1 Span Troubleshooting — Continued
Displayed
Field Function Indication
Continued on next page