CRITICALPOINT 700/800MHZ BDA/DAS/BBU V3 USER MANUAL
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568 Gibraltar Drive, Milpitas, CA 95035 | +1 408 526 0180
Rev. 1-0-2 Rev. Date: 11-1-2024
6.12 V3 BDA/MU/RU ALARM TROUBLESHOOTING
This section provides a guide to troubleshoot each type of individual system alarm for a BDA or Fiber DAS
system. See below for a description of the cause of each alarm and the remedy to troubleshoot/fix the alarm.
DL P_in Low Alarm 700MHz, DL P_in Low Alarm 800MHz
The Composite Downlink Input Power is lower than the user-defined DL P_in low threshold.
When the Composite Downlink Input Power is higher than the user-defined DL P_in low
threshold, the system will clear this alarm. Check donor antenna and cable installation.
DL P_out Low Alarm 700MHz, DL P_out Low Alarm 800MHz
The Composite Downlink Output Power is lower than the user-defined DL P_out low threshold.
When the Composite Downlink Output Power is higher than the user-defined DL P_out low
threshold, the system will clear this alarm. Check donor antenna and cable installation.
DL P_in Over Alarm 700MHz, DL P_in Over Alarm 800MHz
The Composite Downlink Input Power is higher than the user-defined DL P_in Over threshold.
When the Composite Downlink Input Power is lower than the user-defined DL P_in Over
threshold, the system will clear this alarm. Check DL Composite Input from the donor antenna
and use DL Input ATT to reduce to >10dB below the alarm threshold.
DL P_out Over Alarm 700MHz, DL P_out Over Alarm 800MHz, UL P_out Over Alarm
700/800MHz
The Composite Downlink/Uplink Output Power is higher than the user-defined DL P_out Over
threshold or the user-defined UL P_out Over threshold.
When the Composite Downlink/Uplink Output Power is lower than the user-defined DL P_out
Over threshold or the user-defined UL P_out Over threshold, the system will clear this alarm. If
the default setting is used, the P_out Over threshold is set ABOVE the MAX Composite Power,
and the alarm should only occur if the BDA AGC circuits have failed. If the user chooses to
lower the threshold BELOW the MAX Composite Power, the alarm will only indicate the Output
Power is above the user-defined threshold. In this case only an advisory alarm.
LNA Alarm DL 700MHz, LNA Alarm DL 800MHz, LNA Alarm UL 700/800MHz
A fault has been detected in the LNA. The LNA (Low Noise Amplifier) is located at the front-
end of the RF link for both downlink and uplink paths. For the LNA status, the BDA constantly
measures the current going through the LNA. When the current draw is abnormal (e.g., short or
open) indicating a malfunctioned LNA, the system will trigger the alarm. A malfunctioned LNA
could be caused by high input power, high reflect power, or a potential faulty LNA. The power a
LNA can normally handle is < 0dBm (refer to datasheets for actual models).
Measure the Composite Input Power to the BDA over time. If high attenuate accordingly. If a
high Composite Input is not seen, and the alarm will not clear, contact Technical Support.
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