User Manual

ADCP-75-179 • Preliminary Issue A • September 2004 • Section 4: maintenance
Page 4-13
© 2004, ADC Telecommunications, Inc.
3.3 LPA Troubleshooting
During normal operation of the 35 Watt LPA, all LED’s should be Off. When troubleshooting
the LPA, always check the LPA front panel display for messages before initiating a reset or
replacing the LPA. The display will generally indicate the reason for the alarm.
Table 4-8. 35 Watt LPA Fault Isolation and Corrective Action
LED: FAIL Color: Yellow Alarm Type: Major
PROBLEM: Internal fault detected in the LPA.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. The STM to LPA connecting cable is faulty.
2. The LPA has failed.
1. Inspect cable and repair or replace if faulty.
2. Replace LPA
LED: SHUTDOWN Color: Red Alarm Type: Major
PROBLEM: The RF output from the LPA is shutdown.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1.The RF ON/OFF switch is in the OFF position
2. The LPA is in the forced shutdown mode
(single front fan unit) or internal shutdown
mode (dual front fan unit).
3. Breaker switch on LPA is open
4. The LPA is faulty.
1. Place RF ON/OFF switch in the ON position
2. Watch the LED Display and note reason for the
forced shutdown. Refer to the Display Message
section of this table for the recommended correc-
tive action.
3. Reset breaker switch.
4. Replace LPA.
DISPLAY MESSAGE FORCED/INTERNAL SHUTDOWN Alarm Type: LOOP FAIL
PROBLEM: Internal fault detected in the LPA.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. The LPA has failed. 1. Replace LPA
DISPLAY MESSAGE FORCED/INTERNAL SHUTDOWN Alarm Type: DC FAIL
PROBLEM: Internal fault detected in the LPA.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. The LPA has failed. 1. Replace LPA
DISPLAY MESSAGE FORCED/INTERNAL SHUTDOWN Alarm Type: LOW POWER ALARM
PROBLEM: Internal fault detected in the LPA.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. The LPA has failed. 1. Replace LPA
DISPLAY MESSAGE FORCED/INTERNAL SHUTDOWN Alarm Type: FANFAIL
PROBLEM: Internal fault detected in the LPA.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. Both LPA fans have failed. 1. Replace both LPA fans. To reset, use EMS to
place Digivance system in standby mode and
then place system back in normal mode.