ADC PG-Plus PRL-784, Technical Practice

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SCP-PRL784-022-03H Fault Isolation
PG-Plus PRL-784 January 6, 2003 15
Fault LED On • indicates an existing alarm condition on the COLU
1 At the VT-100 interface, go to the COLU Main Screen to view the Performance
report to determine the cause of the alarm. Correct the condition, if possible. If you
cannot view the COLU Main Screen, a communication error exists.
2 Remove and re-insert the COLU.
3 If the communication error still exists, replace the COLU.
M
argin
LED On • distance limitation exceeded
• fault in HDSL line.
• faulty COLU
1 At the VT-100 interface, go to the COLU Main Screen to view the Performance
report to verify that no alarms exist.
2 Initial installation, check engineering records for distance between COTS and RT.
3 If existing installation, measure loss of HDSL line to ensure that the maximum
attenuation value has not been exceeded.
4 Replace COLU and/or the RT.
Margin LED
Flashing • distance limitation exceeded
• fault in HDSL line
• faulty RT
1 Initial installation, check engineering records for distance between COTS and RT.
2 If existing installation, measure loss of HDSL line to ensure that the maximum
attenuation value has not been exceeded.
3 Replace COLU and/or the RT.
SYNC LED Off • HDSL line has lost synchronization
• distance limitation may have been exceeded
• COLU is faulty
1 Initial installation, check engineering records for distance between COTS and RT.
2 If existing installation, measure loss of HDSL line to ensure that the maximum
attenuation value has not been exceeded.
3 Replace COLU and/or the RT.
PWR LED Off • no input power
• on-board fuse is blown on COLU
1 Ground fault condition exists.
2 Check input power at COTS backplane with COLU removed.
3 If power is present at COTS backplane, replace the COLU.
PWR LED
Flashing • HDSL line open
• an overload exists
1 Check line continuity and resistance.
2 COLU power supply or RT may be faulty.