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Kaval Telecom Inc.
DCM000000001
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TROUBLESHOOTING
BDA Field Failures are often due to reasons not related to the BDA’s themselves. Before attempting to troubleshoot the BDA,
ensure that the Donor Repeater, the Portable Radios, Antennas and the in-building Distributed Antenna System are all functioning
properly.
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Maintenance & Safety
The BDA has been engineered for easy maintenance and for safe operation. This has been achieved as follows :
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The 28V DC Power-supply is over-rated for actual requirements.
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Boosters are monitored for both Over-current and Under-current (most failures are sensed this way).
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PA’s are monitored for both Over-current and Under-current (most failures are sensed this way).
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Cabinet temperature is monitored for excessive temperature.
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Components are easily removable via quick connect DC and RF connectors.
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Maintenance Philosophy
Field maintenance should require a screwdriver, a multi-meter, spares of each of the active BDA component parts, and a Portable
Radio to monitor off the air signals. There is no requirement to have any test equipment to accomplish most service repairs.
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All BDA component parts have been designed for reliable long life operation.
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The BDA Controller performs ongoing extensive built in diagnostics.
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Corrective action can often be taken without detailed technical knowledge or the need for any test equipment.
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Troubleshooting Procedure
Once it has been determined that the Donor Site and Portable Radio Equipment are performing satisfactorily, and the BDA itself is
suspect, proceed as follows:
1)
Open the BDA door and observe the BDA Controller display. If none of the Status LED’s are lit, and there is nothing
on the Display, then the AC Power and / or Battery Backup Power (if present) has been lost / disconnected, the
BDA’s DC Power Supply has failed, or the BDA Controller itself has failed. Check the AC Circuit Breaker feeding the
AC circuit that powers the BDA, or possibly the AC plug has been pulled. If AC is present, try turning it off, wait 1
minute, then on again; this may clear a DC Power Supply internal thermal fuse that has tripped. Also check that the
Power On/Off Switch
on the BDA Controller is
On
. If AC power appears to be present, then check for
approximately 28 VDC from the BDA DC Power Supply. If there is no DC Voltage at the Power Supply terminals, it
has likely failed. from Also check for 22 to 28 VDC on the Battery terminals if present. If the BDA Controller still has
no lit LED’s or Display Status then the BDA Controller has likely failed.
2)
If the BDA Controller is functioning with any Fault Status indicated, then check the indicated failed component. Over
or Under Current on Boosters, PA’s or Fans may mean that the power and/or control wiring to that component has
been disconnected or is broken, or that the component has failed and needs replacement. Suspected broken or
faulty cables should be disconnected and reconnected to see if the Fault clears.
3)
Over-temperature indications on the BDA Controller may occur as a result of failed Cooling Fans, blocked ventilation
openings, faulty over-heating Boosters or PA’s, or excessive ambient temperature (> 60
o
C).
4)
Other problems may include connector & cable failures or related problems, specification failure in a Booster or PA,
etc. Problems of this sort are best referred to Kaval Service, or other supporting RF Test Lab.
